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Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

High-Power Rf Load  

DOE Patents (OSTI)

A compact high-power RF load comprises a series of very low Q resonators, or chokes [16], in a circular waveguide [10]. The sequence of chokes absorb the RF power gradually in a short distance while keeping the bandwidth relatively wide. A polarizer [12] at the input end of the load is provided to convert incoming TE.sub.10 mode signals to circularly polarized TE.sub.11 mode signals. Because the load operates in the circularly polarized mode, the energy is uniformly and efficiently absorbed and the load is more compact than a rectangular load. Using these techniques, a load having a bandwidth of 500 MHz can be produced with an average power dissipation level of 1.5 kW at X-band, and a peak power dissipation of 100 MW. The load can be made from common lossy materials, such as stainless steel, and is less than 15 cm in length. These techniques can also produce loads for use as an alternative to ordinary waveguide loads in small and medium RF accelerators, in radar systems, and in other microwave applications. The design is easily scalable to other RF frequencies and adaptable to the use of other lossy materials.

Tantawi, Sami G. (San Mateo, CA); Vlieks, Arnold E. (Livermore, CA)

1998-09-01T23:59:59.000Z

2

High Power RF Sources for Accelerators  

SciTech Connect

This presentation describes RF sources developed and under development at Calabazas Creek Research, Inc. for driving high power accelerators and colliders. The RF sources range from L-Band to W-Band and power levels from 10s of kilowatts CW to 200 MW pulsed. The configurations include standard klystrons, multiple beam klystrons, sheet beam devices, and gyroklystrons. The basic parameters are presented with a basic description of operation and applications.

Ives, Lawrence; Read, Michael; Neilson, Jeff; Borchard, Philipp; Mizuhara, Max [Calabazas Creek Research, Inc., 690 Port Drive, San Mateo, CA 94404 (United States); Lawson, Wesley [Insitute for Research in Applied Physics, University of Maryland, College Park, MD 20742 (United States)

2006-11-27T23:59:59.000Z

3

CLIC RF High Power Production Testing Program  

SciTech Connect

The CLIC Power Extraction and Transfer Structure (PETS) is a passive microwave device in which bunches of the drive beam interact with the impedance of the periodically loaded waveguide and generate RF power for the main linac accelerating structure. The demands on the high power production ({approx} 150 MW) and the needs to transport the 100 A drive beam for about 1 km without losses, makes the PETS design rather unique and the operation very challenging. In the coming year, an intense PETS testing program will be implemented. The target is to demonstrate the full performance of the PETS operation. The testing program overview and test results available to date are presented.

Syratchev, I.; Riddone, G.; /CERN; Tantawi, S.G.; /SLAC

2011-11-02T23:59:59.000Z

4

High Frequency High Power RF Generation using a Relativistic...  

NLE Websites -- All DOE Office Websites (Extended Search)

FREQUENCY HIGH POWER RF GENERATION USING A RELATIVISTIC ELECTRON BEAM C. Jing , S. Antipov, P. Schoessow, and A. Kanareykin, Euclid Techlabs LLC, Solon, OH-44139 J.G. Power, M....

5

Active high-power RF switch and pulse compression system  

DOE Patents (OSTI)

A high-power RF switching device employs a semiconductor wafer positioned in the third port of a three-port RF device. A controllable source of directed energy, such as a suitable laser or electron beam, is aimed at the semiconductor material. When the source is turned on, the energy incident on the wafer induces an electron-hole plasma layer on the wafer, changing the wafer's dielectric constant, turning the third port into a termination for incident RF signals, and. causing all incident RF signals to be reflected from the surface of the wafer. The propagation constant of RF signals through port 3, therefore, can be changed by controlling the beam. By making the RF coupling to the third port as small as necessary, one can reduce the peak electric field on the unexcited silicon surface for any level of input power from port 1, thereby reducing risk of damaging the wafer by RF with high peak power. The switch is useful to the construction of an improved pulse compression system to boost the peak power of microwave tubes driving linear accelerators. In this application, the high-power RF switch is placed at the coupling iris between the charging waveguide and the resonant storage line of a pulse compression system. This optically controlled high power RF pulse compression system can handle hundreds of Megawatts of power at X-band.

Tantawi, Sami G. (San Mateo, CA); Ruth, Ronald D. (Woodside, CA); Zolotorev, Max (Mountain View, CA)

1998-01-01T23:59:59.000Z

6

A high-power L-band RF window  

E-Print Network (OSTI)

June. 2001. [3] "700 MHz Window R&D at LBNL", R. Rimmer et.Testing of PEP-II RF Cavity Windows", M. Neubauer et. al. ,A HIGH-POWER L-BAND RF WINDOW* R.A. Rimmer † , G. Koehler,

2001-01-01T23:59:59.000Z

7

RF coupler for high-power CW FEL photoinjector  

SciTech Connect

A high-current emittance-compensated RF photoinjector is a key enabling technology for a high-power CW FEL. The design presently under way is a 100-mA 2.5-cell {pi}-mode, 700-MHz, normal conducting demonstration CW RF photoinjector. This photoinjector will be capable of accelerating 3 nC per bunch with an emittance at the wiggler less than 10 mm-mrad. The paper presents results for the RF coupling from ridged wave guides to hte photoinjector RF cavity. The LEDA and SNS couplers inspired this 'dog-bone' design. Electromagnetic modeling of the coupler-cavity system has been performed using both 2-D and 3-D frequency-domain calculations, and a novel time-domain approach with MicroWave Studio. These simulations were used to adjust the coupling coefficient and calculate the power-loss distribution on the coupling slot. The cooling of this slot is a rather challenging thermal management project.

Kurennoy, S. (Sergey); Young, L. M. (Lloyd M.)

2003-01-01T23:59:59.000Z

8

High power RF test of an 805 MHz RF cavity for a muon cooling channel  

SciTech Connect

We present recent high power RF test results on an 805 MHz cavity for a muon cooling experiment at Lab G in Fermilab. In order to achieve high accelerating gradient for large transverse emittance muon beams, the cavity design has adopted a pillbox like shape with 16 cm diameter beam iris covered by thin Be windows, which are demountable to allow for RF tests of different windows. The cavity body is made from copper with stiff stainless steel rings brazed to the cavity body for window attachments. View ports and RF probes are available for visual inspections of the surface of windows and cavity and measurement of the field gradient. Maximum of three thermo-couples can be attached to the windows for monitoring the temperature gradient on the windows caused by RF heating. The cavity was measured to have Q{sub 0} of about 15,000 with copper windows and coupling constant of 1.3 before final assembling. A 12 MW peak power klystron is available at Lab G in Fermilab for the high power test. The cavity and coupler designs were performed using the MAFIA code in the frequency and the time domain. Numerical simulation results and cold test measurements on the cavity and coupler will be presented for comparisons.

Li, Derun; Corlett, J.; MacGill, R.; Rimmer, R.; Wallig, J.; Zisman, M.; Moretti, A.; Qian, Z.; Wu, V.; Summers, D.; Norem, J.

2002-05-30T23:59:59.000Z

9

The Development of the Electrically Controlled High Power RF Switch and Its Application to Active RF Pulse Compression Systems  

SciTech Connect

In the past decades, there has been increasing interest in pulsed high power RF sources for building high-gradient high-energy particle accelerators. Passive RF pulse compression systems have been used in many applications to match the available RF sources to the loads requiring higher RF power but a shorter pulse. Theoretically, an active RF pulse compression system has the advantage of higher efficiency and compactness over the passive system. However, the key component for such a system an element capable of switching hundreds of megawatts of RF power in a short time compared to the compressed pulse width is still an open problem. In this dissertation, we present a switch module composed of an active window based on the bulk effects in semiconductor, a circular waveguide three-port network and a movable short plane, with the capability to adjust the S-parameters before and after switching. The RF properties of the switch module were analyzed. We give the scaling laws of the multiple-element switch systems, which allow the expansion of the system to a higher power level. We present a novel overmoded design for the circular waveguide three-port network and the associated circular-to-rectangular mode-converter. We also detail the design and synthesis process of this novel mode-converter. We demonstrate an electrically controlled ultra-fast high power X-band RF active window built with PIN diodes on high resistivity silicon. The window is capable of handling multi-megawatt RF power and can switch in 2-300ns with a 1000A current driver. A low power active pulse compression experiment was carried out with the switch module and a 375ns resonant delay line, obtaining 8 times compression gain with a compression ratio of 20.

Guo, Jiquan; /SLAC

2009-03-20T23:59:59.000Z

10

High-power testing of PEP-II RF cavity windows  

SciTech Connect

We describe the high power testing of RF cavity windows for the PEP-II B factory. The window is designed for continuous operation at 476 MHz with up to 500 kW throughput and has been tested to full power using a modified PEP Klystron. The windows use an anti-multipactor coating on the vacuum side and the application and processing of this layer is discussed. The high power test configuration, RF processing history and high power performance are described.

Neubauer, M.; Allen, M.; Fant, K.; Hill, A.; Hoyt, M.; Judkins, J.; Schwarz, H. [Stanford Linear Accelerator Center, CA (United States); Rimmer, R.A. [Lawrence Berkeley National Lab., CA (United States)

1996-06-01T23:59:59.000Z

11

C-Band High Power RF Generation and Extraction Using a Dielectric...  

NLE Websites -- All DOE Office Websites (Extended Search)

C-BAND HIGH POWER RF GENERATION AND EXTRACTION USING A DIELECTRIC LOADED WAVEGUIDE* F. Gao , M. Conde, W. Gai, R. Konecny, W. Liu, J. Power, Z. Yusof ANL, Argonne, IL 60439,...

12

Report on High Power rf Testing of Quartz Based DLA Structure  

NLE Websites -- All DOE Office Websites (Extended Search)

2 March, 2006 Report on High Power rf Testing of Quartz Based DLA Structure at NRL C. Jing, and R. Konecny Abstract: In this article, we report the experimental results of high...

13

New high power 200 MHz RF system for the LANSCE drift tube linac  

SciTech Connect

The Los Alamos Neutron Science Center (LANSCE) linac provides an 800 MeV direct H{sup +} proton beam, and injects H{sup {minus}} to the upgraded proton storage ring for charge accumulation for the Short Pulse Spallation Source. Accelerating these interlaced beams requires high average power from the 201.25 MHz drift tube linac (DTL) RF system. Three power amplifiers have operated at up to three Megawatts with 12% duty factor. The total number of electron power tubes in the RF amplifiers and their modulators has been reduced from fifty-two to twenty-four. The plant continues to utilize the original design of a tetrode driving a super power triode. Further increases in the linac duty factor are limited, in part, by the maximum dissipation ratings of the triodes. A description of the system modifications proposed to overcome these limitations includes new power amplifiers using low-level RF modulation for tank field control. The first high power Diacrode{reg_sign} is being delivered and a new amplifier cavity is being designed. With only eight power tubes, the new system will deliver both peak power and high duty factor, with lower mains power and cooling requirements. The remaining components needed for the new RF system will be discussed.

Lyles, J.; Friedrichs, C.; Lynch, M.

1998-12-31T23:59:59.000Z

14

RF Power Degradation of GaN High Electron Mobility Transistors  

E-Print Network (OSTI)

We have developed a versatile methodology to systematically investigate the RF reliability of GaN High-Electron Mobility Transistors. Our technique utilizes RF and DC figures of merit to diagnose the degradation of RF ...

Joh, Jungwoo

15

RF Distribution System for High Power Test of the SNS Cryomodule  

Science Conference Proceedings (OSTI)

A four-way waveguide RF power distribution system for testing the Spallation Neutron Source (SNS) multi-cavity cryomodule to investigate the collective behavior has been developed. A single klystron operating at 805MHz for 1.3 msec at 60Hz powers the 4-way waveguide splitter to deliver up to 400 kW to individual cavities. Each cavity is fed through a combination of waveguide splitters and vector modulators (VM) to provide independent magnitude and phase controls. The waveguide vector modulator consists of two quadrature hybrids and two motorized waveguide phase shifters. The phase shifters and the assembled waveguide vector modulators were individually tested and characterized for low power and high RF power in the SNS RF test facility. Precise calibrations of magnitude and phase were performed to generate the look up tables (LUTs) to provide operational references during the cryomodule test. An I-Q demodulator module was developed and utilized to measure relative phases in pulsed high RF power operation. PLC units were developed for mechanical control of the phase shifters. Initial low/high power measurements were made using LabVIEW. An operation algorithm has been implemented into EPICS control for the cryomodule test stand.

Lee, Sung-Woo [ORNL; Kang, Yoon W [ORNL; Broyles, Michael R [ORNL; Crofford, Mark T [ORNL; Geng, Xiaosong [ORNL; Kim, Sang-Ho [ORNL; Phibbs, Curtis L [ORNL; Strong, William Herb [ORNL; Peglow, Robert C [ORNL; Vassioutchenko, Alexandre V [ORNL

2012-01-01T23:59:59.000Z

16

High power tests of dressed supconducting 1.3 GHz RF cavities  

SciTech Connect

A single-cavity test cryostat is used to conduct pulsed high power RF tests of superconducting 1.3 GHz RF cavities at 2 K. The cavities under test are welded inside individual helium vessels and are outfitted ('dressed') with a fundamental power coupler, higher-order mode couplers, magnetic shielding, a blade tuner, and piezoelectric tuners. The cavity performance is evaluated in terms of accelerating gradient, unloaded quality factor, and field emission, and the functionality of the auxiliary components is verified. Test results from the first set of dressed cavities are presented here.

Hocker, A.; Harms, E.R.; Lunin, A.; Sukhanov, A.; /Fermilab

2011-03-01T23:59:59.000Z

17

The design of a high efficiency RF power amplifier for an MCM process  

E-Print Network (OSTI)

In this thesis, I addressed issues arising in the design of a high efficiency RF power amplifier for the Draper Laboratory multi-chip module (MCM) process. A design for a 2.3 GHz PCB amplifier using an enhancement-mode ...

Noonan, James (James Keating)

2005-01-01T23:59:59.000Z

18

Development of fundamental power coupler for high-current superconducting RF cavity  

SciTech Connect

Brookhaven National Laboratory took a project of developing a 704 MHz five-cell superconducting RF cavity for high-current linacs, including Energy Recovery Linac (ERL) for planned electron-hadron collider eRHIC. The cavity will be fed by a high-power RF amplifier using a coaxial Fundamental Power Coupler (FPC), which delivers 20 kW of CW RF power to the cavity. The design of FPC is one of the important aspects as one has to take into account the heat losses dissipated on the surface of the conductor by RF fields along with that of the static heat load. Using a simple simulation model we show the temperature profile and the heat load dissipated along the coupler length. To minimize the heat load on FPC near the cavity end, a thermal intercept is required at an appropriate location on FPC. A 10 K intercept was chosen and its location optimized with our simulation code. The requirement on the helium gas flow rate for the effective heat removal from the thermal intercept is also discussed.

Jain P.; Belomestnykh, S.; Ben-Zvi, I.; Xu, W.

2012-05-20T23:59:59.000Z

19

RF couplers for normal-conducting photoinjector of high-power CW FEL  

SciTech Connect

A high-current emittance-compensated RF photoinjector is a key enabling technology for a high-power CW FEL. A preliminary design of a normal-conducting, 2.5-cell pi-mode, 700-MHz CW RF photoinjector that will be built for demonstration purposes, is completed. This photoinjector will be capable of accelerating a 100-mA electron beam (3 nC per bunch at 35 MHz bunch repetition rate) to 2.7 MeV while providing an emittance below 7 mm-mrad at the wiggler. More than 1 MW of RF power will be fed into the photoinjector cavity through two ridge-loaded tapered waveguides. The waveguides are coupled to the cavity by 'dog-bone' irises cut in a thick wall. Due to CW operation of the photoinjector, the cooling of the coupler irises is a rather challenging thermal management project. This paper presents results of a detailed electromagnetic modeling of the coupler-cavity system, which has been performed to select the coupler design that minimizes the iris heating due to RF power loss in its walls.

Kurennoy, S. (Sergey)

2004-01-01T23:59:59.000Z

20

RF Couplers for Normal-Conducting Photoinjector of High-Power CW FEL  

E-Print Network (OSTI)

A high-current emittance-compensated RF photoinjector is a key enabling technology for a high-power CW FEL. A preliminary design of a normal-conducting, 2.5-cell pi-mode, 700-MHz CW RF photoinjector that will be built for demonstration purposes, is completed. This photoinjector will be capable of accelerating a 100-mA electron beam (3 nC per bunch at 35 MHz bunch repetition rate) to 2.7 MeV while providing an emittance below 7 mm-mrad at the wiggler. More than 1 MW of RF power will be fed into the photoinjector cavity through two ridge-loaded tapered waveguides. The waveguides are coupled to the cavity by "dog-bone" irises cut in a thick wall. Due to CW operation of the photoinjector, the cooling of the coupler irises is a rather challenging thermal management project. This paper presents results of a detailed electromagnetic modeling of the coupler-cavity system, which has been performed to select the coupler design that minimizes the iris heating due to RF power loss in its walls.

Kurennoy, Sergey; Wood, Richard L; Schultheiss, T J; Rathke, John; Young, Lloyd

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

High power testing of the 402.5 MHZ and 805 MHZ RF windows for the spallation neutron source accelerator  

SciTech Connect

Hisorically, Radio Frequency (RF) windows have been a common point of failure in input power couplers; therefore, reliable RF windows are critical to the success of the Spallation Neutron Source (SNS) project. The normal conducting part of the SNS accelerator requires six RF windows at 402.5 MHz and eight RF windows at 805 MHz[l]. Each RF window will transmit up to 180 kW of average power and 2.5 MW peak power at 60 Hz with 1.2 millisecond pulses. The RF windows, designed and manufactured by Thales, were tested at the full average power for 4 hours to ensure no problems with the high average power and then tested to an effective forward power level of 10 MW by testing at 2.5 MW forward power into a short and varying the phase of the standing wave. The sliding short was moved from 0 to 180 degrees to ensure no arcing or breakdown problems occur in any part of the window. This paper discusses the results of the high power testing of both the 402.5 MHz and the 805 MHz RF windows. Problems encountered during testing and the solutions for these problems are discussed.

Cummings, K. A. (Karen Ann); De Baca, J. M. (John M.); Harrison, J. S. (John S.); Rodriguez, M. B. (Manuelita B.); Torrez, P. A. (Phillip A.); Warner, D. K. (David K.)

2003-01-01T23:59:59.000Z

22

HIGH POWER TEST OF RF SEPARATOR FOR 12 GEV UPGRADE OF CEBAF AT JLAB  

Science Conference Proceedings (OSTI)

CEBAF at JLab is in the process of an energy upgrade from 6 GeV to 12 GeV. The existing setup of the RF separator cavities in the 5th pass will not be adequate to extract the highest energy (11 GeV) beam to any two existing halls (A, B or C) while simultaneously delivering to the new hall D in the case of the proposed 12 GeV upgrade of the machine. To restore this capability, we are exploring the possibility of extension of existing normal conducting 499 MHz TEM-type rf separator cavities. Detailed numerical studies suggest that six 2-cell normal conducting structures meet the requirements; each 2-cell structure will require up to 4 kW RF input power in contrast with the current nominal operating power of 1.0 to 2.0 kW. A high power test of 4 kW confirms that the cavity meet the requirement.

S. Ahmed, M. Wissmann, J. Mammosser, C. Hovater, M. Spata, G. Krafft, J. Delayen

2012-07-01T23:59:59.000Z

23

Active high-power RF pulse compression using optically switched resonant delay lines  

DOE Green Energy (OSTI)

The authors present the design and a proof of principle experimental results of an optically controlled high power rf pulse compression system. The design should, in principle, handle few hundreds of Megawatts of power at X-band. The system is based on the switched resonant delay line theory. It employs resonant delay lines as a means of storing rf energy. The coupling to the lines is optimized for maximum energy storage during the charging phase. To discharge the lines, a high power microwave switch increases the coupling to the lines just before the start of the output pulse. The high power microwave switch, required for this system, is realized using optical excitation of an electron-hole plasma layer on the surface of a pure silicon wafer. The switch is designed to operate in the TE{sub 01} mode in a circular waveguide to avoid the edge effects present at the interface between the silicon wafer and the supporting waveguide; thus, enhancing its power handling capability.

Tantawi, S.G.; Ruth, R.D.; Vlieks, A.E. [Stanford Univ., CA (US). Stanford Linear Accelerator Center; Zolotorev, M. [Lawrence Berkeley National Lab., CA (US)

1996-11-01T23:59:59.000Z

24

Optical diagnostics for a high power, rf-inductively coupled plasma  

SciTech Connect

Emission spectroscopy and laser-induced fluorescence have been used to monitor the field and tail-flame regions of a Hull-design inductively coupled plasma. This plasma is used for a variety of syntheses including SiC, TiC, BN, A1N and diamond. Temporally- and spatially-resolved spectra of both pure Ar and Ar/gas mixtures have been studied as a function of RF power, pressure and flow rate. Preliminary data suggest that the system is far from local thermodynamic equilibrium.

Nogar, N.S.; Keaton, G.L.; Anderson, J.E.; Trkula, M.

1988-01-01T23:59:59.000Z

25

High Power Testing Results of the X-band Mixed-mode RF Windows for Linear Colliders  

SciTech Connect

In this paper, we summarize the high power testing results of the X-band mixed-mode RF windows at KEK and SLAC for linear colliders. The main feature of these windows is that the combination of modes on the surface of the ceramic significantly decreases the electric and magnetic fields in the junction between the ceramic and the metal. So far two types of high power windows (with the diameter of 53 mm and 64 mm) have been fabricated. A high power model of the smaller type window was fabricated and tested in a resonant ring at KEK. A maximum circulating power of 81 MW with 300 ns duration or 66 MW with 700 ns duration was achieved. Light emission was observed for a power level of over 10 MW. Later, both windows were shipped to SLAC for even higher power testing using combined power from two klystrons. The first window (53 mm diameter) achieved a transmitted power of 80 MW with 1.5 microsec duration at 30 Hz repetition. It was not destroyed during the testing. The testing of the second window was carried out next to the small type and achieved 62 MW with 1.5 microsec duration with 10 Hz repetition. The final results of both windows are presented in this report.

Loewen, Roderick J

2000-10-26T23:59:59.000Z

26

Recent advances in RF power generation  

SciTech Connect

This paper is a review of the progress and methods used in RF generation for particle accelerators. The frequencies of interest are from a few megahertz to 100 GHz, and the powers are for super linear collider applications, but in this case the pulses are short, generally below 1 {mu}s. The very high-power, short-pulse generators are only lightly reviewed here, and for more details the reader should follow the specialized references. Different RF generators excel over various parts of the frequency spectrum. Below 100 MHz solid-state devices and gridded tubes prevail, while the region between 400 MHz and 3 GHz, the cyclotron-resonant devices predominate, and above 250 GHz, Free-Electron Lasers and ubitrons are the most powerful generators. The emphasis for this review is on microwave generation at frequencies below 20 GHz, so the cyclotron-resonant devices are only partially reviewed, while the progress on free-electron laser and ubitrons is not reviewed in this paper. 39 refs., 4 figs.

Tallerico, P.J.

1990-01-01T23:59:59.000Z

27

Electrodeless lighting RF power source development. Final report  

SciTech Connect

An efficient, solid state RF power source has been developed on this NICE project for exciting low power electrodeless lamp bulbs. This project takes full advantage of concurrent advances in electrodeless lamp technology. Electrodeless lamp lighting systems utilizing the sulfur based bulb type developed by Fusion Lighting, Inc., is an emerging technology which is based on generating light in a confined plasma created and sustained by RF excitation. The bulb for such a lamp is filled with a particular element and inert gas at low pressure when cold. RF power from the RF source creates a plasma within the bulb which reaches temperatures approaching those of high pressure discharge lamp plasmas. At these temperatures the plasma radiates substantial visible light with a spectrum similar to sunlight.

NONE

1996-08-30T23:59:59.000Z

28

rf modulator design and phase amplitude control for a high-power free-electron-laser linac  

SciTech Connect

The continued interest for building tunable lasers using an electron accelerator as the source of primary energy has resulted in the design of a new accelerator. Earlier work by other members of the Los Alamos team has demonstrated that this design does work in an amplifier mode. The accelerator is to be upgraded for use in an oscillator experiment and the new rf power amplifier system must meet some of the very stringent demands for power and stability placed on the electron beam for the free-electron laser (FEL) interaction to be observed. These demands are particularly stringent because the electron beam energy ultimately will be circulated back through the accelerator so that the electron beam energy not used in the FEL interaction is not wasted. These considerations have to some measure been incorporated into the design of the second FEL system at Los Alamos and are discussed.

Hoeberling, R.F.; Tallerico, P.J.

1981-01-01T23:59:59.000Z

29

High voltage RF feedthrough bushing  

DOE Patents (OSTI)

Described is a multi-element, high voltage radio frequency bushing for trmitting RF energy to an antenna located in a vacuum container. The bushing includes a center conductor of complex geometrical shape, an outer coaxial shield conductor, and a thin-walled hollow truncated cone insulator disposed between central and outer conductors. The shape of the center conductor, which includes a reverse curvature portion formed of a radially inwardly directed shoulder and a convex portion, controls the uniformity of the axial surface gradient on the insulator cone. The outer shield has a first substantially cylindrical portion and a second radially inwardly extending truncated cone portion.

Grotz, Glenn F. (Huntington Station, NY)

1984-01-01T23:59:59.000Z

30

Microsoft PowerPoint - rf_5year_review  

NLE Websites -- All DOE Office Websites (Extended Search)

RF Research Program RF Research Program DOE Review of C-Mod Five-Year Proposal May 13-14, 2003 MIT PSFC Presented by Steve J.Wukitch Outline: 1. Overview of the RF Program 2. Five-year plan Overview of the RF Program AT: validate steady state operation with target parameters β N = 3, I non = 100%, I BS ~ 70%, H 89 ~ 2.5, for t pulse > t L/R . BPX: demonstrate the viability of high performance plasmas, B T = 8T, I p = 2 MA, P = 6 MW, H 89 ≥ 2, Z eff < 1.5. B T = 5.4T, I p = 1.4 MA, P = 6 MW, H 89 = 2 (ITER demo) Exclusively use RF power for auxiliary heating and current drive. variable variable fixed Phase 2 x 4 Strap 4 Strap 2 x 2 Strap Antenna 4 MW 40-80 MHz J-port 2 x 4 MW 2 x 2 MW Power 40-80 MHz ~ 80 MHz Frequency E & J-port D & E-port 2005-2008 2002-2005 4.6 GHz 4.6 GHz Frequency 16 x 250 kW

31

IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 55, NO. 4, APRIL 2008 1067 Nonuniform RF Overstress in High-Power  

E-Print Network (OSTI)

voltage (VRF) across a loop, which is strongly affected by internal reflections in the device and mismatch effects. In some cases, nonuniformity in VRF occurs due to parasitic oscillations excited under actual). Digital Object Identifier 10.1109/TED.2008.916719 RF stress. Monitoring the spatial distribution of VRF

Shapira, Yoram

32

Influence of Substrate Temperature and RF Power on the Formation ...  

Science Conference Proceedings (OSTI)

Presentation Title, Influence of Substrate Temperature and RF Power on the Formation of ZnO Nanorods for Solar Driven Hydrogen Production. Author(s) ...

33

Efficiency enhancement techniques for RF and millimeter wave power amplifiers  

E-Print Network (OSTI)

Power amplifiers are the circuit blocks in wireless transceivers that require the largest power budget because of their relatively low efficiencies. RF designers cannot depend solely on the development better semiconductor ...

Ogunnika, Olumuyiwa Temitope, 1978-

2012-01-01T23:59:59.000Z

34

Rf power systems for the national synchrotron light source  

SciTech Connect

The booster synchrotron and the two storage rings at the NSLS are provided with rf power systems of 3 kW, 50 kW, and 500 kW nominal output power, all at 53 MHz. This power is supplied by grounded grid tetrode amplifiers designed for television broadcast service. These amplifiers and associated power supplies, control and interlock systems, rf controls, and computer interface are described.

Dickinson, T.; Rheaume, R.H.

1981-01-01T23:59:59.000Z

35

RF breakdown effects in microwave power amplifiers  

E-Print Network (OSTI)

Electrical stresses in the transistors of high-efficiency switching power amplifiers can lead to hot-electron-induced "breakdown" in these devices. This thesis explores issues related to breakdown in the Transcom TC2571 ...

Arumilli, Gautham Venkat

2007-01-01T23:59:59.000Z

36

Deeply scaled CMOS for RF power applications  

E-Print Network (OSTI)

The microelectronics industry is striving to reduce the cost, complexity, and form factor of wireless systems through single-chip integration of analog, RF and digital functions. Driven by the requirements of the digital ...

Scholvin, Jörg, 1976-

2006-01-01T23:59:59.000Z

37

Low-power/low-voltage RF microsystems for wireless sensors networks  

Science Conference Proceedings (OSTI)

This paper presents radio-frequency (RF) microsystems (MSTs) composed by low-power devices for use in wireless sensors networks (WSNs). The RF CMOS transceiver is the main electronic system and its power consumption is a critical issue. Two RF CMOS transceivers ... Keywords: RF CMOS transceiver, RF microsystems, Wireless sensors networks

J. P. Carmo; J. H. Correia

2009-12-01T23:59:59.000Z

38

Delta-Sigma digital-RF modulation for high data rate transmitters  

E-Print Network (OSTI)

A low power, wideband wireless transmitter utilizing [Delta]-[Sigma] direct digital modulation of an RF carrier is presented. The transmitter architecture replaces high dynamic range analog circuits with high speed digital ...

Jerng, Albert

2007-01-01T23:59:59.000Z

39

Extremely high frequency RF effects on electronics.  

SciTech Connect

The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit board traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.

Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale; Williams, Jeffery Thomas; Wouters, Gregg A.; Bacon, Larry Donald; Mar, Alan

2012-01-01T23:59:59.000Z

40

A 12 GHz RF Power Source for the CLIC Study  

SciTech Connect

The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.

Schirm, Karl; /CERN; Curt, Stephane; /CERN; Dobert, Steffen; /CERN; McMonagle, Gerard; /CERN; Rossat, Ghislain; /CERN; Syratchev, Igor; /CERN; Timeo, Luca; /CERN; Haase, Andrew /SLAC; Jensen, Aaron; /SLAC; Jongewaard, Erik; /SLAC; Nantista, Christopher; /SLAC; Sprehn, Daryl; /SLAC; Vlieks, Arnold; /SLAC; Hamdi, Abdallah; /Saclay; Peauger, Franck; /Saclay; Kuzikov, Sergey; /Nizhnii Novgorod, IAP; Vikharev, Alexandr; /Nizhnii Novgorod, IAP

2012-07-03T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

New architecture for RF power amplifier linearization  

E-Print Network (OSTI)

Power amplifier linearization has become an important part of the transmitter system as 3G and developing 4G communication standards require higher linearity than ever before. The thesis proposes two power amplifier ...

Boo, Hyun H

2009-01-01T23:59:59.000Z

42

RF Power Upgrade for CEBAF at Jefferson Laboratory  

Science Conference Proceedings (OSTI)

Jefferson Laboratory (JLab) is currently upgrading the 6GeV Continuous Electron Beam Accelerator Facility (CEBAF) to 12GeV. As part of the upgrade, RF systems will be added, bringing the total from 340 to 420. Existing RF systems can provide up to 6.5 kW of CW RF at 1497 MHZ. The 80 new systems will provide increased RF power of up to 13 kW CW each. Built around a newly designed and higher efficiency 13 kW klystron developed for JLab by L-3 Communications, each new RF chain is a completely revamped system using hardware different than our present installations. This paper will discuss the main components of the new systems including the 13 kW klystron, waveguide isolator, and HV power supply using switch-mode technology. Methodology for selection of the various components and results of initial testing will also be addressed. Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

Andrew Kimber,Richard Nelson

2011-03-01T23:59:59.000Z

43

Available Technologies: High Efficiency Spiral RF-Induction ...  

The spiral antennas efficient use of source geometry also ... Neutron and high energy gamma ... A typical RF-induction plasma generator with a ...

44

The upgraded rf system for the AGS and high intensity proton beams  

SciTech Connect

The AGS has been upgraded over the past three years to produce a record beam intensity of 6 {times} 10{sup 13} protons per pulse for the fixed-target physics program. The major elements of the upgrade are: the new 1.5 GeV Booster synchrotron, the main magnet power supply, a high frequency longitudinal dilution cavity, a feedback damper for transverse instabilities, a fast gamma transition jump system, and a new high-power rf system. The new rf system and its role in achieving the high intensity goal are the subjects of this report. The rf system is heavily beam loaded, with 7 Amps of rf current in the beam and a peak power of 0.75 MW delivered to the beam by ten cavities. As an example of the scale of beam loading, at one point in the acceleration cycle the cavities are operated at 1.5 kV/gap; whereas, were it not for the new power amplifiers, the beam-induced voltage on the cavities would be over 25 kV/gap. The upgraded rf system, comprising: new power amplifiers, wide band rf feedback, improved cavities, and new low-level beam control electronics, is described. Results of measurements with beam, which characterize the system`s performance, are presented. A typical high intensity acceleration cycle is described with emphasis on the key challenges of beam loading.

Brennan, J.M. [Brookhaven National Lab., Upton, NY (United States). AGS Dept.

1995-05-01T23:59:59.000Z

45

Proposal for high pressure RF cavity test in the MTA  

DOE Green Energy (OSTI)

In order to demonstrate the feasibility of high pressure hydrogen gas filled RF (HPRF) cavities for muon ionization cooling, an HPRF cavity must be tested with a high intensity charged beam. When an HPRF cavity is irradiated with an intense beam each incident particle generates about 1000 electrons and ions per cubic centimeter in a high pressure cavity via ionization. These ionization electrons are influenced by the RF field and the RF quality factor goes down. This Q factor reduction will be a problem with a multi bunch beam, e.g., a muon beam for a muon collider consists of a 12 to 20 bunch train beam with 5 ns timing gap. Thus, the RF field must recover in few nano seconds. We propose to use a 400 MeV proton beam in the MTA and measure a beam loading effect in the HPRF cavity and study the recovery mechanism of the RF field.

Yonehara, K.; /Fermilab

2010-09-01T23:59:59.000Z

46

rf  

NLE Websites -- All DOE Office Websites (Extended Search)

RF RF It's what makes the protons go 'round. The latest in a series explaining particle physics in everyday language. Painless Physics Articles BEAM COOLING August 2, 1996 By Leila Belkora, Office of Public Affairs ACCELERATION August 16, 1996 By Dave Finley, Accelerator Division Head RF August 30, 1996 By Pat Colestock, Accelerator Division FIXED TARGET PHYSICS September 20, 1996 By Peter H. Garbincius, Physics Section FIXED TARGET PHYSICS PART DEUX October 16, 1996 By Peter H. Garbincius, Physics Section and Leila Belkora, Office of Public Affaris CROSS SECTION November 1, 1996 By Doreen Wackeroth, Theoretical Physics Edited by Leila Belkora, Office of Public Affaris MAGNETS PART I November 15, 1996 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs

47

Design of a new VHF RF power amplifier system for LANSCE  

Science Conference Proceedings (OSTI)

A major upgrade is replacing much of the 40 year-old proton drift tube linac RF system with new components at the Los Alamos Neutron Science Center (LANSCE). When installed, the new system will reduce the total number of electron power tubes from twenty-four to eight in the RF powerplant. A new 200 MHz high power cavity amplifier has being developed at LANSCE. This 3.2 MW final power amplifier (FPA) uses a Thales TH628 Diacrode{reg_sign}, a state-of-the-art tetrode that eliminates the large anode modulator of the triode-based FPA that has been in use for four decades. Drive power for the FPA is provided by a new tetrode intermediate power amplifier (and a solid-state driver stage). The new system has sufficient duty-factor capability to allow LANSCE to return to 1 MW beam operation. Prototype RF power amplifiers have been designed, fabricated, and assembled, and are being tested. High voltage DC power became available through innovative re-engineering of an installed system. Details of the electrical and mechanical design of the FPA and ancillary systems are discussed.

Lyles, John T M [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

48

rf power system for thrust measurements of a helicon plasma source  

SciTech Connect

A rf power system has been developed, which allows the use of rf plasma devices in an electric propulsion test facility without excessive noise pollution in thruster diagnostics. Of particular importance are thrust stand measurements, which were previously impossible due to noise. Three major changes were made to the rf power system: first, the cable connection was changed from a balanced transmission line to an unbalanced coaxial line. Second, the rf power cabinet was placed remotely in order to reduce vibration-induced noise in the thrust stand. Finally, a relationship between transmission line length and rf was developed, which allows good transmission of rf power from the matching network to the helicon antenna. The modified system was tested on a thrust measurement stand and showed that rf power has no statistically significant contribution to the thrust stand measurement.

Kieckhafer, Alexander W.; Walker, Mitchell L. R. [Department of Aerospace Engineering, High-Power Electric Propulsion Laboratory, College of Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2010-07-15T23:59:59.000Z

49

RF heating and current drive on NSTX with high  

SciTech Connect

NSTX is a small aspect ratio tokamak (R = 0.85 m, a = 0.65 m). The High Harmonic Fast Wave (HHFW) system is a 30 MHz, 12-element array capable of launching both symmetric and directional wave spectra for plasma heating and non-inductive current drive. It has delivered up to 6 MW for short pulses and has routinely operated at ~3 MW for 100-400 ms pulses. Results include strong, centrally-peaked electron heating in both D and He plasmas for both high and low phase velocity spectra. H-modes were obtained with application of HHFW power alone, with stored energy doubling after the L-H transition. Beta poloidal as large as unity has been obtained with significant fractions (0.4) of bootstrap current. Differences in the loop voltage are observed depending on whether the array is phased to drive current in the co- or counter-current directions. A fast ion tail with energies extending up to 140 keV has been observed when HHFW interacts with 80 keV neutral beams; neutron rate and lost ion measurements, as well as modeling, indicate significant power absorption by the fast ions. Radial rf power deposition and driven current profiles have been calculated with ray tracing and kinetic full-wave codes and compared with measurements.

Ryan, Philip Michael [ORNL; Peng, Yueng Kay Martin [ORNL

2003-01-01T23:59:59.000Z

50

CMOS RF Power Amplifier Design for Wireless Communications  

E-Print Network (OSTI)

Kim, J. Laskar, "Power-combining Transformer Techniques forUsing a Novel On-Chip Transformer Power Combiner in StandardBroadband Power Amplifier With a Transformer-Based High-

FANG, Qiang

2012-01-01T23:59:59.000Z

51

Fermilab Tevatron high level rf accelerating systems  

SciTech Connect

Eight tuned rf cavities have been installed and operated in the F0 straight section of the Tevatron. Their mechanical placement along the beam line enables them to be operated for colliding beams as two independent groups of four cavities, group 1-4 accelerating antiprotons and group 5-8 accelerating protons. The only difference is that the spacing between cavities 4 and 5 was increased to stay clear of the F0 colliding point. The cavities can easily be rephased by switching cables in a low-level distribution system (fan-out) so that the full accelerating capability of all eight cavities can be used during fixed target operations. Likewise, the cables from capacitive probes on each cavity gap can be switched to proper lengths and summed in a fan-back system to give an rf signal representing the amplitude and phase as ''seen by the beam,'' separately for protons and antiprotons. Such signals have been used to phase lock the Tevatron to the Main Ring for synchronous transfer.

Kerns, Q.; Kerns, C.; Miller, H.; Tawser, S.; Reid, J.; Webber, R.; Wildman, D.

1985-06-01T23:59:59.000Z

52

An Efficient Supply Modulator for Linear Wideband RF Power Amplifiers  

E-Print Network (OSTI)

Radio Frequency (RF) Power Amplifiers are responsible for a considerable amount of the power consumption in the entire transmitter-receiver (transceiver) of modern communication systems. The stringent linearity requirements of multi-standard transceivers to minimize cross-talking effects makes Linear Power Amplifiers, particularly class A, the preferred choice in broadband transceivers. This linearity requirement coupled with the fact that the Power Amplifier operates at low transmit power during most of its operation makes the efficiency of the entire transceiver poor. The limited transceiver efficiency leads to a reduction in the battery life of battery operated portable devices like mobile phones; hence drastically limiting talk time. To alleviate this issue, several research groups propose solutions to improve PA power efficiency. However, these solutions usually have a low efficiency at low power and are mostly limited to narrow bandwidth applications. In this thesis, the efficiency of a class A Power amplifier in wideband wireless standards like WiMax is improved by dynamically controlling the bias current and supply voltage of the PA. An efficient supply modulator based on a switching regulator architecture is proposed for controlling the supply voltage. The switching regulator is found to be slew-limited by the bulky inductor and capacitor used to regulate the supply voltage. The proposed solution alleviates the slew rate limitation by adding a bang-bang controlled current source. The proposed supply modulator has an average power efficiency of 81.6 percent and is suitable for wireless standards with bandwidths up to 20MHz compared to the relatively lower efficiencies and bandwidths of state of the art modulators. A class-A PA is shown to promise an average power efficiency of 21.3 percent when the bias current is controlled dynamically and the supply voltage is varied using the proposed supply modulator. This is a significant improvement over the poor average efficiency of 1.06 percent for a fixed bias conventional linear class A PA. The project has been simulated using the TSMC 0.18 micrometer technology.

Turkson, Richard

2011-08-01T23:59:59.000Z

53

RF Conditioning and testing of fundamental power couplers for the RIA project  

DOE Green Energy (OSTI)

The Rare Isotope Accelerator (RIA) is the highest priority of the nuclear physics community in the United States for a major new accelerator facility. A principal element of RIA will be a superconducting 1.4 GeV superconducting ion linac accelerating ions of isotopes from hydrogen to uranium onto production targets or for further acceleration by a second superconducting linac. The superconducting linac technology is closely related to that used at existing accelerators and the Spallation Neutron Source. Taking advantage of JLAB's SRF Institute facilities and expertise for the SNS project, preparation of couplers, RF conditioning and high power tests have been performed on fundamental power couplers for RIA project.

M. Stirbet; J. Popielarski; T. L. Grimm; M. Johnson

2003-09-01T23:59:59.000Z

54

Low temperature rf sputtering deposition of (Ba, Sr) TiO{sub 3} thin film with crystallization enhancement by rf power supplied to the substrate  

SciTech Connect

The (Ba, Sr) TiO{sub 3} thin film deposited by radio frequency (rf) sputtering requires a high deposition temperature near 500 deg. C to realize a high relative dielectric constant over of 300. For example, the film deposited at 330 deg. C contains an amorphous phase and shows a low relative dielectric constant of less than 100. We found that rf power supplied not only to the (Ba, Sr) TiO{sub 3} sputtering target, but also to the substrate during the initial step of film deposition, enhanced the crystallization of the (Ba, Sr) TiO{sub 3} film drastically and realized a high dielectric constant of the film even at low deposition temperatures near 300 deg. C. The 50-nm-thick film with only a 10 nm initial layer deposited with the substrate rf biasing is crystallized completely and shows a high relative dielectric constant of 380 at the deposition temperature of 330 deg. C. The (Ba, Sr) TiO{sub 3} film deposited at higher temperatures (upwards of 400 deg. C) shows <110> preferred orientation, while the film deposited at 330 deg. C with the 10 nm initial layer shows a <111> preferred orientation on a <001>-oriented ruthenium electrode. The unit cell of (Ba, Sr) TiO{sub 3} (111) plane is similar to that of ruthenium (001) plane. We conclude that the rf power supplied to the substrate causes ion bombardments on the (Ba, Sr) TiO{sub 3} film surface, which assists the quasiepitaxial growth of (Ba, Sr) TiO{sub 3} film on the ruthenium electrode at low temperatures of less than 400 deg. C.

Yoshimaru, Masaki; Takehiro, Shinobu; Abe, Kazuhide; Onoda, Hiroshi [System LSI Research Division, Silicon Solution Company, Oki Electric Industry Co., Ltd., 550-1, Higashi-asakawa, Hachioji, Tokyo 193-8550 (Japan); Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Strategic Planning Office, Silicon Manufacturing Company, Oki Electric Industry Co., Ltd., 550-1, Higashi-asakawa, Hachioji, Tokyo 193-8550 (Japan)

2005-05-01T23:59:59.000Z

55

Optimal RF Conditioning of Advanced Photon Source (APS) Fundamental Power Coupler  

E-Print Network (OSTI)

Experience at many laboratories regarding conditioning of RF Fundamental Power Couplers (FPC) has shown that it is a very apprehensive and laborious process. While the principle should remain unchanged, which is to gradually increase the rf power applied to the coupler while monitoring the vacuum level, the methodology is sometime different. With coupler lifetime being finite, some RF conditioning methods may be more conservative than others. The basic principle of coupler conditioning is to avoid the phenomena of metallisation, violent electrical discharges or other possible destructive phenomena. This document summarizes an optimized method which has demonstrated its effectiveness and for which the fundamental principles are: • Regulate RF power as a function of vacuum pressure around the coupler as fast as possible. • Apply a longer repetition period than the vacuum reading delay. • Follow the bare principle: low energy for low risk, by delivering pulses to the not yet conditioned coupler, initially...

Montesinos, E

2013-01-01T23:59:59.000Z

56

Influence of Intense Beam in High Pressure Hydrogen Gas Filled RF Cavities  

DOE Green Energy (OSTI)

The influence of an intense beam in a high-pressure gas filled RF cavity has been measured by using a 400 MeV proton beam in the Mucool Test Area at Fermilab. The ionization process generates dense plasma in the cavity and the resultant power loss to the plasma is determined by measuring the cavity voltage on a sampling oscilloscope. The energy loss has been observed with various peak RF field gradients (E), gas pressures (p), and beam intensities in nitrogen and hydrogen gases. Observed RF energy dissipation in single electron (dw) in N{sub 2} and H{sub 2} gases was 2 10{sup -17} and 3 10{sup -17} Joules/RF cycle at E/p = 8 V/cm/Torr, respectively. More detailed dw measurement have been done in H{sub 2} gas at three different gas pressures. There is a clear discrepancy between the observed dw and analytical one. The discrepancy may be due to the gas density effect that has already been observed in various experiments.

Yonehara, K.; Chung, M.; Collura, M.G.; Jana, M.R.; Leonova, M.; Moretti, A.; Popovic, M.; Schwarz, T.; Tollestrup, A.; /Fermilab; Johnson, R.P.; Franagan, G.; /Muons, Inc. /IIT

2012-05-01T23:59:59.000Z

57

High-power accelerator technology and requirements  

SciTech Connect

Designs of high-power proton linear accelerators (linacs) for accelerator transmutation of waste (ATW) are being actively studied at Los Alamos National Laboratory and at several other laboratories worldwide. Beam parameters cover the 100- to 300-mA range in average current and 800 to 1600 MeV in energy. While ideas for such accelerators have been discussed for decades, the technology base has recently advanced to the point that the feasibility of machines in the ATW power class is now generally conceded. Factors contributing to this advance have been the following: experience gained with medium-power research accelerators, especially the LAMPF linac at Los Alamos; major improvements in the theory and technology of high-intensity high-brightness accelerators fostered by the SDIO Neutral Particle Beam program; and development of high-power continuous-wave (cw) radio-frequency (rf) generators for high-energy colliding-beam rings. The reference ATW accelerator concept described in this paper is based on room-temperature copper accelerating cavities. Advances in superconducting niobium cavity technology have opened the possibility of application to ATW-type linacs. Useful efficiency gains could be realized, especially for lower current systems, and there may be technical advantages as well. Technology issues that need to be addressed for superconducting rf linac designs include the development of high-power rf couplers, appropriate cavity designs, and superconducting focusing elements, as well as concerns about beam damage of niobium structures and dynamic rf control with high beam currents.

Lawrence, G.P. (Los Alamos National Lab., NM (United States))

1993-01-01T23:59:59.000Z

58

High Gradient Operation with the CEBAF Upgrade RF Control System  

SciTech Connect

The CEBAF Accelerator at Jefferson Lab is presently a 6 GeV five pass electron accelerator consisting of two superconducting linacs joined by independent magnetic transport arcs. Energy will be upgraded to 12 GeV with the addition of 10 new high gradient cryomodules (17+ MV/m). The higher gradients pose significant challenges beyond what the present analog low level RF (LLRF) control systems can handle reliably; therefore, a new LLRF control system is needed. A prototype system has been developed incorporating a large FPGA and using digital down and up conversion to minimize the need for analog components. The new system is more flexible and less susceptible to drifts and component nonlinearities. Because resonance control is critical to reach high gradients quickly, the new cryomodules will include a piezoelectric tuner for each cavity, and the LLRF controls must incorporate both feedback and feed-forward methods to achieve optimal resonance control performance. This paper discusses development of the new RF system, system performance for phase and amplitude stability and resonance control under Lorentz detuning measured during recent tests on a prototype cryomodule.

J. Hovater; G. Davis; Hai Dong; Alicia Hofler; Lawrence King; John Musson; Tomasz Plawski

2006-08-16T23:59:59.000Z

59

Performance evaluation of indoor localization techniques based on RF power measurements from active or passive devices  

Science Conference Proceedings (OSTI)

The performance of networks for indoor localization based on RF power measurements from active or passive devices is evaluated in terms of the accuracy, complexity, and costs. In the active device case, the terminal to be located measures the power transmitted ...

Damiano De Luca; Franco Mazzenga; Cristiano Monti; Marco Vari

2006-01-01T23:59:59.000Z

60

High power variable couplers for ladder and spoke type resonators  

Science Conference Proceedings (OSTI)

Superconducting RF structures such as spoke resonators [1] have been developed which will accelerate very low velocity ions. This opens up the possibility for the use of these resonators in high power proton accelerators at energies as low as the output energies of typical RFQs. Most similar resonators have been used for the acceleration of ions requiring only low RF power input. In new applications such as for the Accelerator Transmutation of Nuclear Wastes (ATW) and Accelerator Production of Tritium (APT), higher RF power will be required because of the larger beam currents. This paper discusses some higher power variable coupler concepts that could be used with these structures.

Spalek, G. (George); Kuzminski, J. (Jozef)

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

RF Design and Operating Results for a New 201.25 MHz RF Power Amplifier for LANSCE  

SciTech Connect

A prototype VHF RF Final Power Amplifier (FPA) for Los Alamos Neutron Science Center (LANSCE) has been designed, fabricated, and tested. The cavity amplifier has met the goals of generating 2.5 MW peak and 260 kW of average power, at an elevation of 2.1 km. It was designed to use a Thales TH628 Diacrode{sup R}, a state-of-art tetrode power tube that is double-ended, providing roughly twice the power of a conventional tetrode. The amplifier is designed with tunable input and output transmission line cavity circuits, a grid decoupling circuit, an adjustable output coupler, TE mode suppressors, blocking, bypassing and decoupling capacitors, and a cooling system. The tube is connected in a full wavelength output circuit, with the lower main tuner situated 3/4{lambda} from the central electron beam region in the tube and the upper slave tuner 1/4{lambda} from the same point. We summarize the design processes and features of the FPA along with significant test results. A pair of production amplifiers are planned to be power-combined and installed at the LANSCE DTL to return operation to full beam duty factor.

Lyles, John T. [Los Alamos National Laboratory; Baca, David M. [Los Alamos National Laboratory; Bratton, Ray E. [Los Alamos National Laboratory; Brennan, Nicholas W. [Los Alamos National Laboratory; Bultman, Nathan K. [Los Alamos National Laboratory; Chen, Zukun [Los Alamos National Laboratory; Davis, Jerry L. [Los Alamos National Laboratory; Naranjo, Angela C. [Los Alamos National Laboratory; Rees, Daniel E. [Los Alamos National Laboratory; Sandoval, Gilbert M. Jr. [Los Alamos National Laboratory; Summers, Richard D. [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

62

Plasma sweeper to control the coupling of RF power to a magnetically confined plasma  

DOE Patents (OSTI)

A device for coupling RF power (a plasma sweeper) from a phased waveguide array for introducing RF power to a plasma having a magnetic field associated therewith comprises at least one electrode positioned near the plasma and near the phased waveguide array; and a potential source coupled to the electrode for generating a static electric field at the electrode directed into the plasma and having a component substantially perpendicular to the plasma magnetic field such that a non-zero vector cross-product of the electric and magnetic fields exerts a force on the plasma causing the plasma to drift.

Motley, Robert W. (Princeton, NJ); Glanz, James (Lawrenceville, NJ)

1985-01-01T23:59:59.000Z

63

RF-MEMS capacitive switches with high reliability  

DOE Patents (OSTI)

A reliable long life RF-MEMS capacitive switch is provided with a dielectric layer comprising a "fast discharge diamond dielectric layer" and enabling rapid switch recovery, dielectric layer charging and discharging that is efficient and effective to enable RF-MEMS switch operation to greater than or equal to 100 billion cycles.

Goldsmith, Charles L.; Auciello, Orlando H.; Carlisle, John A.; Sampath, Suresh; Sumant, Anirudha V.; Carpick, Robert W.; Hwang, James; Mancini, Derrick C.; Gudeman, Chris

2013-09-03T23:59:59.000Z

64

A high-gradient high-duty-factor RF photo-cathode electron gun  

Science Conference Proceedings (OSTI)

We describe the analysis and preliminary design of a high-gradient, high-duty factor RF photocathode gun. The gun is designed to operate at high repetition rate or CW, with high gradient on the cathode surface to minimize emittance growth due to space charge forces at high bunch charge. The gun may also be operated in a solenoidal magnetic field for emittance compensation. The design is intended for use in short-pulse, high-charge, and high-repetition rate applications such as linac based X-ray sources. We present and compare the results of gun simulations using different codes, as well as RF and thermal analysis of the structure.

Robert Rimmer; N. Hartman; S. Lidia; S.H. Wang

2002-08-01T23:59:59.000Z

65

Characterization of MEMS sensor for RF transmitted power measurement  

Science Conference Proceedings (OSTI)

In this report we introduce the procedure for performing a thermo mechanical design and analysis of thermal GaAs-based MEMS devices. It will provide the procedure how thermal analysis should be made and model equations used to describe conduction, convection, ... Keywords: GaAs microsystems, MEMS, power sensor, thermal converter, thermo-mechanical simulations

Jiri Jakovenko; Miroslav Husak

2006-03-01T23:59:59.000Z

66

814 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 50, NO. 3, MARCH 2002 Power Amplifiers and Transmitters for RF  

E-Print Network (OSTI)

resistances. The 1990s saw a proliferation of a variety of new solid-state devices including HEMT, pHEMT, HFET, linearity, and cost. RF power is generated by a wide variety of techniques, implementations, and active of generating and controlling RF signals, and vacuum-tube PAs were dominant from the late 1920s through the mid

Popovic, Zoya

67

IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 55, NO. 10, OCTOBER 2007 2043 Power Supply Rejection for RF Amplifiers  

E-Print Network (OSTI)

from noise or voltage ripple on the power supply. As demonstrated in Fig. 1, spectral energy injected the interaction of supply noise with RF amplifier components for successful design of the system. In the context noted, the op- erator is not fully symmetric in this representation because the supply noise and RF

Sanders, Seth

68

RF Cherenkov picosecond timing technique for high energy physics applications  

Science Conference Proceedings (OSTI)

The Cherenkov time-of-propagation (TOP) detector and Cherenkov time-of-flight (TOF) detector in a ?head-on? geometry based on the recently proposed time measuring technique with radio frequency (RF) phototube are considered. Results of the Monte Carlo simulations are presented.

Margaryan, Amur; Hashimoto, Osamu; Majewski, Stanislaw; Tang, Liguang

2008-09-01T23:59:59.000Z

69

A high sensitivity ultralow temperature RF conductance and noise measurement setup  

SciTech Connect

We report on the realization of a high sensitivity RF noise measurement scheme to study small current fluctuations of mesoscopic systems at milli-Kelvin temperatures. The setup relies on the combination of an interferometric amplification scheme and a quarter-wave impedance transformer, allowing the measurement of noise power spectral densities with gigahertz bandwidth up to five orders of magnitude below the amplifier noise floor. We simultaneously measure the high frequency conductance of the sample by derivating a portion of the signal to a microwave homodyne detection. We describe the principle of the setup, as well as its implementation and calibration. Finally, we show that our setup allows to fully characterize a subnanosecond on-demand single electron source. More generally, its sensitivity and bandwidth make it suitable for applications manipulating single charges at GHz frequencies.

Parmentier, F. D.; Mahe, A.; Denis, A.; Berroir, J.-M.; Glattli, D. C.; Placais, B.; Feve, G. [Laboratoire Pierre Aigrain, Ecole Normale Superieure, CNRS UMR 8551, Universite P. et M. Curie, Universite D. Diderot 24, rue Lhomond, 75231 Paris Cedex 05 (France)

2011-01-15T23:59:59.000Z

70

High gain proportional rf control stability at TESLA cavities Elmar Vogel  

E-Print Network (OSTI)

High gain proportional rf control stability at TESLA cavities Elmar Vogel Deutsches Elektronen) based on TESLA technology. Additional control loops improve the field regulation by treating repetitive loops is desirable for the strong suppression of nonpredictive and nonrepetitive disturbances. TESLA

71

Exploring predistortion training algorithms in a Cartesian feedback-trained digital predistortion system for RF power amplifier linearization  

E-Print Network (OSTI)

A Cartesian feedback-trained digital predistortion system for RF power amplifier linearization offers many advantages with its combination of two different linearization techniques. This thesis describes such a system, ...

Huang, Jeffrey B

2006-01-01T23:59:59.000Z

72

Mechanical Design and Fabrication of a New RF Power Amplifier for LANSCE  

SciTech Connect

A Full-scale prototype of a new 201.25 MHz RF Final Power Amplifier (FPA) for Los Alamos Neutron Science Center (LANSCE) has been designed, fabricated, assembled and installed in the test facility. This prototype was successfully tested and met the physics and electronics design criteria. The team faced design and manufacturing challenges, having a goal to produce 2 MW peak power at 13% duty factor, at the elevation of over 2 km in Los Alamos. The mechanical design of the final power amplifier was built around a Thales TH628 Diacrode{sup R}, a state-of-art tetrode power tube. The main structure includes Input circuit, Output circuit, Grid decoupling circuit, Output coupler, Tuning pistons, and a cooling system. Many types of material were utilized to make this new RF amplifier. The fabrication processes of the key components were completed in the Prototype Fabrication Division shop at Los Alamos National Laboratory. The critical plating procedures were achieved by private industry. The FPA mass is nearly 600 kg and installed in a beam structural support stand. In this paper, we summarize the FPA design basis and fabrication, plating, and assembly process steps with necessary lifting and handling fixtures. In addition, to ensure the quality of the FPA support structure a finite element analysis with seismic design forces has also been carried out.

Chen, Zukun [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

73

Use of a Geographic Mapping Tool in Power Line Routing for RF Hazard Identification: A Feasibility Evaluation  

Science Conference Proceedings (OSTI)

Radiofrequency (RF) fields induce currents and voltages on conductive objects with the general finding that larger or longer or taller objects, such as power lines and tall cranes, can result in greater currents and voltages. Medium wave frequencies (MF) associated with operation of AM radio broadcast stations are particularly prone to induction of RF voltages on long and/or tall cables that present the potential for arcing to ground or personnel who may initiate contact with the conductor. MF includes t...

2011-11-16T23:59:59.000Z

74

Stray RF Power Estimates From EC Exploitation During ITER Plasma Operations  

SciTech Connect

The EC H and CD system of ITER tokamak is an essential tool for all the phases of ITER operation. Different levels of EC power are required through all the plasma discharge: up to 6.7 MW for assisting the breakdown and burn through, up to 20 MW for current drive and saw-teeth control from the equatorial launcher and up to 20 MW for NTM stabilization from the upper launchers. The assistance to breakdown and burn through is characterized by a very low (if not negligible) RF power absorption by the plasma. A significant level of stray radiation may also arise from partial absorption due to non-optimal plasma parameters and/or wrong injected polarization. The stray power radiated in the vacuum chamber is estimated as a first step toward mitigating potential harmful consequence to in-vessel structures and diagnostics. Power loading of the chamber walls (peek power and average power density for straight beam propagation in the empty chamber) and diffuse stray radiation effects are simulated to infer suitable strategies to avoid damage to first wall and to microwave sensitive components.

Gandini, F.; Henderson, M.; Darbos, C.; Gassmann, T.; Purohit, D.; Omori, T. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Nazare, C. [Assystem Facilities, 78067 Saint Quentin en Yvelines Cedex (France)

2011-12-23T23:59:59.000Z

75

Soft Magnetic Materials for High Power and High Frequency Power ...  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and ... are in high demand for the next generation of miniaturized power electronics.

76

High power microwave generator  

DOE Patents (OSTI)

A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

Ekdahl, C.A.

1983-12-29T23:59:59.000Z

77

High power microwave generator  

DOE Patents (OSTI)

A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

Ekdahl, Carl A. (Albuquerque, NM)

1986-01-01T23:59:59.000Z

78

Low temperature high density Si3N4 MIM capacitor technology for MMMIC and RF-MEMs applications  

Science Conference Proceedings (OSTI)

In this work, a novel, high quality, high-density, deposited at room temperature ultra thin 5 nm Si3N4 metal insulator metal (MIM) capacitor process for monolithic millimetre-wave integrated circuit (MMMIC) applications ... Keywords: RF MEMs, RF MIM capacitors, dielectric films, high density capacitors, room temperature ultra thin silicon nitride films metal insulator metal capacitors

K. Elgaid; H. Zhou; C. D. W. Wilkinson; I. G. Thayne

2004-06-01T23:59:59.000Z

79

DESIGN CONSIDERATIONS FOR LOW FIELD SHORT PHOTO-INJECTED RF ELECTRON GUN WITH HIGH CHARGE ELECTRON BUNCH.  

Science Conference Proceedings (OSTI)

The RF field and space charge effect in a low field RF gun is given. The cell lengths are modified to have maximum accelerating efficiency. The modification introduces an extra RF field slice emittance. The phase space evolution of the following emittance compensation system is presented taking into account the chromatic effect. The emittance compensation mechanics for RF field and chromatic effect induced emittance is similar to that of compensating the space charge induced emittance. But the requirements are different to have best compensation for them. The beam waist is far in front of linac entrance to have best compensation for the RF field and chromatic effect induced emittance. For low field RF gun with high charge electron bunch this compensation is more important.

CHANG,X.; BEN-ZVI,I.; KEWISCH,J.

2004-06-21T23:59:59.000Z

80

High brightness symmetric emittance rf photoinjector preliminary design report  

SciTech Connect

A preliminary design for a high bunch charge (8 nC), low emittance (< 20 mm-mr) radiofrequency electron photoinjector matched to the requirements of the Tesla Test Facility is presented. A 1.5 cell iris coupled {pi}mode structure with high average accelerating gradient is chosen for its high shunt impedance, simplicity, and ability to accommodate an externally mounted solenoid for simultaneous beam divergence control and emittance compensation. Beam optics are optimized for an overall injector consisting of the electron gun followed by one linac capture section, a dipole chicane for magnetic bunch compression to achieve a bunch length corresponding to {sigma}{sub z} = 1 mm. Electrical and beam dynamical aspects of the photoinjector design are presented. A description of the proposed experimental program is included.

Colby, E.R.; Ostiguy, J.F. [Fermi National Accelerator Lab., Batavia, IL (United States); Rosenzweig, J.B. [California Univ., Los Angeles, CA (United States). Dept. of Physics

1994-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Progress on the high-current 704 MHz superconducting RF cavity at BNL  

Science Conference Proceedings (OSTI)

The 704 MHz high current superconducting cavity has been designed with consideration of both performance of fundamental mode and damping of higher order modes. A copper prototype cavity was fabricated by AES and delivered to BNL. RF measurements were carried out on this prototype cavity, including fundamental pass-band and HOM spectrum measurements, HOM studies using bead-pull setup, prototyping of antenna-type HOM couplers. The measurements show that the cavity has very good damping for the higher-order modes, which was one of the main goals for the high current cavity design. 3D cavity models were simulated with Omega3P code developed by SLAC to compare with the measurements. The paper describes the cavity design, RF measurement setups and results for the copper prototype. The progress with the niobium cavity fabrication will also be described.

Xu W.; Astefanous, C.; Belomestnykh, S.; Ben-Zvi, I.; et al

2012-05-20T23:59:59.000Z

82

High power windows for WR650 waveguide couplers  

Science Conference Proceedings (OSTI)

Based on the robust, pre-stressed planar window concept successfully tested for PEP II and LEDA, a new design for planar ceramic windows to be used with WR650 waveguide fundamental power couplers at 1300 MHz or 1500 MHz has been developed. These windows should operate in pulsed or CW mode and sustain at least 100 kW average power levels. This paper describes an overview of the simulations performed to match the ceramics in WR650 waveguides, design details, as well as the RF measurements and performance assessed by RF power tests on several high power windows manufactured at JLAB. Funding Agency: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177, and by The Office of Naval Research under contract to the Dept. of Energy.

Mircea Stirbet; Robert Rimmer; Thomas Elliott; Edward Daly; Katherine Wilson; Lynn Vogel; Haipeng Wang; Brian Carpenter; Karl Smith; Thomas Powers; Michael Drury; Robert Nichols; G. Davis

2007-06-01T23:59:59.000Z

83

RF Power Detector/Monitor Upgrade for the 500MHz Systems at the ALS  

E-Print Network (OSTI)

THE 500MHZ SYSTEMS AT THE ALS* K. Baptiste, LBNL, Berkeley,In the Advanced Light Source (ALS) Booster Ring and Storagedetectors in service in the ALS Storage Ring RF System only

Baptiste, K.

2003-01-01T23:59:59.000Z

84

High-Power Options for LANSCE  

SciTech Connect

The LANSCE linear accelerator at Los Alamos National Laboratory has a long history of successful beam operations at 800 kW. We have recently studied options for restoration of high-power operations including approaches for increasing the performance to multi-MW levels. In this paper we will discuss the results of this study including the present limitations of the existing accelerating structures at LANSCE, and the high-voltage and RF systems that drive them. Several options will be discussed and a preferred option will be presented that will enable the first in a new generation of scientific facilities for the materials community. The emphasis of this new facility is 'Matter-Radiation Interactions in Extremes' (MaRIE) which will be used to discover and design the advanced materials needed to meet 21st century national security and energy security challenges.

Garnett, Robert W. [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

85

High Performance RF and Basdband Analog-to-Digital Interface for Multi-standard/Wideband Applications  

E-Print Network (OSTI)

The prevalence of wireless standards and the introduction of dynamic standards/applications, such as software-defined radio, necessitate the next generation wireless devices that integrate multiple standards in a single chip-set to support a variety of services. To reduce the cost and area of such multi-standard handheld devices, reconfigurability is desirable, and the hardware should be shared/reused as much as possible. This research proposes several novel circuit topologies that can meet various specifications with minimum cost, which are suited for multi-standard applications. This doctoral study has two separate contributions: 1. The low noise amplifier (LNA) for the RF front-end; and 2. The analog-to-digital converter (ADC). The first part of this dissertation focuses on LNA noise reduction and linearization techniques where two novel LNAs are designed, taped out, and measured. The first LNA, implemented in TSMC (Taiwan Semiconductor Manufacturing Company) 0.35Cm CMOS (Complementary metal-oxide-semiconductor) process, strategically combined an inductor connected at the gate of the cascode transistor and the capacitive cross-coupling to reduce the noise and nonlinearity contributions of the cascode transistors. The proposed technique reduces LNA NF by 0.35 dB at 2.2 GHz and increases its IIP3 and voltage gain by 2.35 dBm and 2dB respectively, without a compromise on power consumption. The second LNA, implemented in UMC (United Microelectronics Corporation) 0.13Cm CMOS process, features a practical linearization technique for high-frequency wideband applications using an active nonlinear resistor, which obtains a robust linearity improvement over process and temperature variations. The proposed linearization method is experimentally demonstrated to improve the IIP3 by 3.5 to 9 dB over a 2.5–10 GHz frequency range. A comparison of measurement results with the prior published state-of-art Ultra-Wideband (UWB) LNAs shows that the proposed linearized UWB LNA achieves excellent linearity with much less power than previously published works. The second part of this dissertation developed a reconfigurable ADC for multistandard receiver and video processors. Typical ADCs are power optimized for only one operating speed, while a reconfigurable ADC can scale its power at different speeds, enabling minimal power consumption over a broad range of sampling rates. A novel ADC architecture is proposed for programming the sampling rate with constant biasing current and single clock. The ADC was designed and fabricated using UMC 90nm CMOS process and featured good power scalability and simplified system design. The programmable speed range covers all the video formats and most of the wireless communication standards, while achieving comparable Figure-of-Merit with customized ADCs at each performance node. Since bias current is kept constant, the reconfigurable ADC is more robust and reliable than the previous published works.

Zhang, Heng

2010-12-01T23:59:59.000Z

86

Radio-frequency powered glow discharge device and method with high voltage interface  

DOE Patents (OSTI)

A high voltage accelerating potential, which is supplied by a high voltage direct current power supply, is applied to the electrically conducting interior wall of an RF powered glow discharge cell. The RF power supply desirably is electrically grounded, and the conductor carrying the RF power to the sample held by the probe is desirably shielded completely excepting only the conductor's terminal point of contact with the sample. The high voltage DC accelerating potential is not supplied to the sample. A high voltage capacitance is electrically connected in series between the sample on the one hand and the RF power supply and an impedance matching network on the other hand. The high voltage capacitance isolates the high DC voltage from the RF electronics, while the RF potential is passed across the high voltage capacitance to the plasma. An inductor protects at least the RF power supply, and desirably the impedance matching network as well, from a short that might occur across the high voltage capacitance. The discharge cell and the probe which holds the sample are configured and disposed to prevent the probe's components, which are maintained at ground potential, from bridging between the relatively low vacuum region in communication with the glow discharge maintained within the cell on the one hand, and the relatively high vacuum region surrounding the probe and cell on the other hand. The probe and cell also are configured and disposed to prevent the probe's components from electrically shorting the cell's components. 11 figures.

Duckworth, D.C.; Marcus, R.K.; Donohue, D.L.; Lewis, T.A.

1994-06-28T23:59:59.000Z

87

Radio-frequency powered glow discharge device and method with high voltage interface  

DOE Patents (OSTI)

A high voltage accelerating potential, which is supplied by a high voltage direct current power supply, is applied to the electrically conducting interior wall of an RF powered glow discharge cell. The RF power supply desirably is electrically grounded, and the conductor carrying the RF power to the sample held by the probe is desirably shielded completely excepting only the conductor's terminal point of contact with the sample. The high voltage DC accelerating potential is not supplied to the sample. A high voltage capacitance is electrically connected in series between the sample on the one hand and the RF power supply and an impedance matching network on the other hand. The high voltage capacitance isolates the high DC voltage from the RF electronics, while the RF potential is passed across the high voltage capacitance to the plasma. An inductor protects at least the RF power supply, and desirably the impedance matching network as well, from a short that might occur across the high voltage capacitance. The discharge cell and the probe which holds the sample are configured and disposed to prevent the probe's components, which are maintained at ground potential, from bridging between the relatively low vacuum region in communication with the glow discharge maintained within the cell on the one hand, and the relatively high vacuum region surrounding the probe and cell on the other hand. The probe and cell also are configured and disposed to prevent the probe's components from electrically shorting the cell's components.

Duckworth, Douglas C. (Knoxville, TN); Marcus, R. Kenneth (Clemson, SC); Donohue, David L. (Vienna, AT); Lewis, Trousdale A. (Oak Ridge, TN)

1994-01-01T23:59:59.000Z

88

The Jefferson Lab High Power Light Source  

Science Conference Proceedings (OSTI)

Jefferson Lab has designed, built and operated two high average power free-electron lasers (FEL) using superconducting RF (SRF) technology and energy recovery techniques. Between 1999-2001 Jefferson Lab operated the IR Demo FEL. This device produced over 2 kW in the mid-infrared, in addition to producing world record average powers in the visible (50 W), ultraviolet (10 W) and terahertz range (50 W) for tunable, short-pulse (power demonstration of an accelerator configuration that is being exploited for a number of new accelerator-driven light source facilities that are currently under design or construction. The driver accelerator for the IR Demo FEL uses an Energy Recovered Linac (ERL) configuration that improves the energy efficiency and lowers both the capital and operating cost of such devices by recovering most of the power in the spent electron beam after optical power is extracted from the beam. The IR Demo FEL was de-commissioned in late 2001 for an upgraded FEL for extending the IR power to over 10 kW and the ultraviolet power to over 1 kW. The FEL Upgrade achieved 10 kW of average power in the mid-IR (6 microns) in July of 2004, and its IR operation currently is being extended down to 1 micron. In addition, we have demonstrated the capability of on/off cycling and recovering over a megawatt of electron beam power without diminishing machine performance. A complementary UV FEL will come on-line within the next year. This paper presents a summary of the FEL characteristics, user community accomplishments with the IR Demo, and planned user experiments.

James R. Boyce

2006-01-01T23:59:59.000Z

89

Design of RF Feed System for Standing-Wave Accelerator Structures  

Science Conference Proceedings (OSTI)

We are investigating a standing wave accelerator structure that uses a rf feed to each individual cell. This approach minimizes rf power flow and electromagnetic energy absorbed by an rf breakdown. The objective of this work is a robust high-gradient (above 100 MV/m) X-band accelerator structure.

Neilson, J.; Tantawi, S.; Dolgashev, V.; /SLAC

2012-05-25T23:59:59.000Z

90

A 26 GHz Dielectric Based Wakefield Power Extractor  

NLE Websites -- All DOE Office Websites (Extended Search)

26GHz high power rf source based on the extraction of wakefields from a relativistic electron beam. The extractor is designed to couple out rf power generated from a high charge...

91

High frequency inductive lamp and power oscillator  

DOE Patents (OSTI)

A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and I or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to adjust the driving frequency of the oscillator.

MacLennan, Donald A. (Gaithersburg, MD); Dymond, Jr., Lauren E. (North Potomac, MD); Gitsevich, Aleksandr (Montgomery Village, MD); Grimm, William G. (Silver Spring, MD); Kipling, Kent (Gaithersburg, MD); Kirkpatrick, Douglas A. (Great Falls, VA); Ola, Samuel A. (Silver Spring, MD); Simpson, James E. (Gaithersburg, MD); Trimble, William C. (Columbia, MD); Tsai, Peter (Olney, MD); Turner, Brian P. (Damascus, MD)

2001-01-01T23:59:59.000Z

92

High frequency inductive lamp and power oscillator  

DOE Patents (OSTI)

A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

MacLennan, Donald A. (Gaithersburg, MD); Turner, Brian P. (Damascus, MD); Dolan, James T. (Frederick, MD); Kirkpatrick, Douglas A. (Great Falls, VA); Leng, Yongzhang (Damascus, MD)

2000-01-01T23:59:59.000Z

93

High deposition rate preparation of amorphous silicon solar cells by rf glow discharge decomposition of disilane  

SciTech Connect

The optical and electrical properties of hydrogenated amorphous silicon films produced by rf glow discharge decomposition of disilane diluted in helium (Si/sub 2/H/sub 6//He = 1/9) have been studied while systematically varying the film deposition rate. The properties and composition of the films were monitored by measuring the optical band gap, IR vibrational spectrum, dark conductivity, and the photoconductivity as a function of the deposition rate. The photoluminescence of the high deposition rate films gave a peak at 1.33 eV. These films, whose properties are rather similar to those of the conventional a-Si:H films prepared from monosilane, have been used to fabricate nip-type a-Si:H solar cells. At a deposition rate of 11 A/sec, a conversion efficiency of 6.86% was obtained. This high efficiency shows that disilane is applicable for mass production fabrication of a-Si:H solar cells.

Kenne, J.; Ohashi, Y.; Matsushita, T.; Konagai, M.; Takahashi, K.

1984-01-15T23:59:59.000Z

94

TRANSISTOR HIGH VOLTAGE POWER SUPPLY  

DOE Patents (OSTI)

High voltage, direct current power supplies are described for use with battery powered nuclear detection equipment. The particular advantages of the power supply described, are increased efficiency and reduced size and welght brought about by the use of transistors in the circuit. An important feature resides tn the employment of a pair of transistors in an alternatefiring oscillator circuit having a coupling transformer and other circuit components which are used for interconnecting the various electrodes of the transistors.

Driver, G.E.

1958-07-15T23:59:59.000Z

95

Experimental Estimate of Beam Loading and Minimum rf Voltage for Acceleration of High Intensity Beam in the Fermilab Booster  

E-Print Network (OSTI)

The difference between the rf voltage seen by the beam and the accelerating voltage required to match the rate of change of the Booster magnetic field is used to estimate the energy loss per beam turn. Because the rf voltage (RFSUM) and the synchronous phase can be experimentally measured, they can be used to calculate the effective accelerating voltage. Also an RFSUM reduction technique has been applied to measure experimentally the RFSUM limit at which the beam loss starts. With information on beam energy loss, the running conditions, especially for the high intensity beam, can be optimized in order to achieve a higher intensity beam from the Fermilab Booster.

Yang, X; Norem, J; Yang, Xi

2004-01-01T23:59:59.000Z

96

Experimental estimate of beam loading and minimum rf voltage for acceleration of high intensity beam in the Fermilab Booster  

SciTech Connect

The difference between the rf voltage seen by the beam and the accelerating voltage required to match the rate of change of the Booster magnetic field is used to estimate the energy loss per beam turn. Because the rf voltage (RFSUM) and the synchronous phase can be experimentally measured, they can be used to calculate the effective accelerating voltage. Also an RFSUM reduction technique has been applied to measure experimentally the RFSUM limit at which the beam loss starts. With information on beam energy loss, the running conditions, especially for the high intensity beam, can be optimized in order to achieve a higher intensity beam from the Fermilab Booster.

Xi Yang; Charles M Ankenbrandt and Jim Norem

2004-04-01T23:59:59.000Z

97

High average power pockels cell  

DOE Patents (OSTI)

A high average power pockels cell is disclosed which reduces the effect of thermally induced strains in high average power laser technology. The pockels cell includes an elongated, substantially rectangular crystalline structure formed from a KDP-type material to eliminate shear strains. The X- and Y-axes are oriented substantially perpendicular to the edges of the crystal cross-section and to the C-axis direction of propagation to eliminate shear strains.

Daly, Thomas P. (Pleasanton, CA)

1991-01-01T23:59:59.000Z

98

Cold Test Measurements on the GTF Prototype RF Gun  

Science Conference Proceedings (OSTI)

The SSRL Gun Test Facility (GTF) was built to develop a high brightness electron injector for the LCLS and has been operational since 1996. Based on longitudinal phase space measurements showing a correlated energy spread the gun was removed and re-characterized in 2002. The low power RF measurements performed on the gun are described below. Perturbative bead measurements were performed to determine the field ratio in the two-cell gun, and network analyzer measurements were made to characterize the mode structure. A second probe was installed to monitor the RF field in the first cell, and a diagnostic was developed to monitor the high-power field ratio. Calibration of the RF probes, a model for analyzing RF measurements, and Superfish simulations of bead and RF measurements are described.

Gierman, S.M.

2010-12-03T23:59:59.000Z

99

RF design of X-band RF deflector for femtosecond diagnostics of LCLS electron beam  

Science Conference Proceedings (OSTI)

We designed a successful constant impedance traveling wave X-band rf deflector for electron beam diagnostics at the 14 GeV SLAC Linac Coherent Light Source (LCLS). This is the first practical deflector built with a waveguide coupler. The 1-meter rf deflector produces 24 MeV peak transverse kick when powered with 20 MW of 11.424 GHz rf. The design is based on our experience with high gradient X-band accelerating structures. Several deflectors of this design have been built at SLAC and are currently in use. Here we describe the design and distinguishing features of this device.

Dolgashev, Valery A.; Wang Juwen [SLAC National Accelerator Laboratory, Menlo Park, CA, 94025 (United States)

2012-12-21T23:59:59.000Z

100

High-Power Plasma Switch for 11.4 GHz Microwave Pulse Compressor  

SciTech Connect

Results obtained in several experiments on active RF pulse compression at X-band using a magnicon as the high-power RF source are presented. In these experiments, microwave energy was stored in high-Q TE01 and TE02 modes of two parallel-fed resonators, and then discharged using switches activated with rapidly fired plasma discharge tubes. Designs and high-power tests of several versions of the compressor are described. In these experiments, coherent pulse superposition was demonstrated at a 5–9 MW level of incident power. The compressed pulses observed had powers of 50–70 MW and durations of 40–70 ns. Peak power gains were measured to be in the range of 7:1–11:1 with efficiency in the range of 50–63%.

Jay L. Hirshfield

2010-03-04T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

High Frequency Power Modulation - TRIMET Smelters Provide ...  

Science Conference Proceedings (OSTI)

Presentation Title, High Frequency Power Modulation - TRIMET Smelters Provide Primary Control Power for Stabilizing the Frequency in the Electricity Grid.

102

High-Average Power Facilities  

SciTech Connect

There has been significant progress in the development of high-power facilities in recent years yet major challenges remain. The task of WG4 was to identify which facilities were capable of addressing the outstanding R&D issues presently preventing high-power operation. To this end, information from each of the facilities represented at the workshop was tabulated and the results are presented herein. A brief description of the major challenges is given, but the detailed elaboration can be found in the other three working group summaries.

Dowell, David H.; /SLAC; Power, John G.; /Argonne

2012-09-05T23:59:59.000Z

103

Initial RF measurements of the CW normal-conducting RF injector  

Science Conference Proceedings (OSTI)

The LANL 2.5-cell, normal-conducting radio-frequency (NCRF) injector has been fabricated. We present initial results of low-power RF measurements (cavity Q, cavity field map, coupling beta, etc.) of the NCRF injector. The measured cavity Q and relative fields are found to be in good agreement with the design calculations and earlier measurements of Glidcop properties. However, the coupling beta of the ridge-loaded waveguides is found to be significantly higher than the design point. The impact of these low-power measurement results on the planned high-power RF and electron beam tests will be discussed.

Krawcyk, Frank L [Los Alamos National Laboratory; Moody, Nathan A [Los Alamos National Laboratory; Martinez, Felix A [Los Alamos National Laboratory; Nguyen, Dinh C [Los Alamos National Laboratory; Bolme, Gerald [Los Alamos National Laboratory; Young, Karen [Los Alamos National Laboratory; Toung, Lloyd [AES

2008-01-01T23:59:59.000Z

104

High power fast ramping power supplies  

Science Conference Proceedings (OSTI)

Hundred megawatt level fast ramping power converters to drive proton and heavy ion machines are under research and development at accelerator facilities in the world. This is a leading edge technology. There are several topologies to achieve this power level. Their advantages and related issues will be discussed.

Marneris,I.; Bajon, E.; Bonati, R.; Sandberg, J.; Roser, T.; Tsoupas, N.

2009-05-04T23:59:59.000Z

105

High power, high beam quality regenerative amplifier  

DOE Patents (OSTI)

A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

Hackel, Lloyd A. (Livermore, CA); Dane, Clifford B. (Livermore, CA)

1993-01-01T23:59:59.000Z

106

High power, high beam quality regenerative amplifier  

DOE Patents (OSTI)

A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

Hackel, L.A.; Dane, C.B.

1993-08-24T23:59:59.000Z

107

High power, high frequency, vacuum flange  

DOE Patents (OSTI)

This invention is comprised of an improved waveguide flange is disclosed for high power operation that helps prevent arcs from being initiated at the junctions between waveguide sections. The flanges at the end of the waveguide sections have counterbores surrounding the waveguide tubes. When the sections are bolted together the counterbores form a groove that holds a fully annealed copper gasket. Each counterbore has a beveled step that is specially configured to insure the gasket forms a metal-to-metal vacuum seal without gaps or sharp edges. The resultant inner surface of the waveguide is smooth across the junctions between waveguide sections, and arcing is prevented.

Felker, B.; McDaniel, M.

1991-12-31T23:59:59.000Z

108

High voltage DC power supply  

DOE Patents (OSTI)

A high voltage DC power supply having a first series resistor at the output for limiting current in the event of a short-circuited output, a second series resistor for sensing the magnitude of output current, and a voltage divider circuit for providing a source of feedback voltage for use in voltage regulation is disclosed. The voltage divider circuit is coupled to the second series resistor so as to compensate the feedback voltage for a voltage drop across the first series resistor. The power supply also includes a pulse-width modulated control circuit, having dual clock signals, which is responsive to both the feedback voltage and a command voltage, and also includes voltage and current measuring circuits responsive to the feedback voltage and the voltage developed across the second series resistor respectively. 7 figs.

Droege, T.F.

1989-12-19T23:59:59.000Z

109

Photocathode emission studies: Dark current and Schottky-enabled photo-electrons in a high-field RF gun  

Science Conference Proceedings (OSTI)

We report on dark current and Schottky-enabled photoemission from a copper photocathode surface. Field-emitted dark current is a major gradient-limiting factor in RF cavities. Field emission is generally attributed to geometrical projections on the bulk surface whose field enhancement factor ({beta}) and the emitting area (A{sub e}) can be extracted from the Fowler-Nordheim (FN) plot. Measurements were made at Tsinghua S-band RF gun facility in two separate experiments. Using the traditional FN formula for RF fields we discovered that field enhancement factor ({beta}) alone cannot explain the full data set. Instead, we found that a low work function at some sites is required. In addition, surface analysis of the cathode after the experiment shows that geometric {beta} indicated would be < 10. Thus we conclude that low work function sites with a small {beta} are responsible for dark current emission and subsequent breakdown in high-gradient structures. The origin of these sites is unclear but could be due to defects or impurities.

Chen, H.; Du, Y.; Gai, W.; Grudiev, A.; Hua, J.; Huang, W.; Power, J.; Wisniewski, E. E.; Wuensch, W.; Tang, C.; Yan, L.; You, Y. [Dept. of Eng. Phys., Tsinghua U. (China); ANL/HEP, Argonne, IL (United States); CERN, Geneva (Switzerland); Dept. of Eng. Phys., Tsinghua U. (China); ANL/HEP, Argonne, IL (United States); ANL/HEP, Argonne, IL (United States) and IIT Chicago, IL (United States); CERN, Geneva (Switzerland); Dept. of Eng. Phys., Tsinghua U. (China)

2012-12-21T23:59:59.000Z

110

Recent Studies of RF Breakdown Physics in Normal Conducting Cavities  

SciTech Connect

The operating accelerating gradient in normal conducting accelerating structures is often limited by rf breakdown. The behavior of the rf breakdown depends on multiple parameters, including the input rf power, rf circuit, cavity shape and material. Here we discuss recent experimental data and theoretical studies of rf breakdown physics.

Dolgashev, Valery; /SLAC

2012-06-11T23:59:59.000Z

111

RUGGED CERAMIC WINDOW FOR RF APPLICATIONS  

Science Conference Proceedings (OSTI)

High-current RF cavities that are needed for many accelerator applications are often limited by the power transmission capability of the pressure barriers (windows) that separate the cavity from the power source. Most efforts to improve RF window design have focused on alumina ceramic, the most popular historical choice, and have not taken advantage of new materials. Alternative window materials have been investigated using a novel Merit Factor comparison and likely candidates have been tested for the material properties which will enable construction in the self-matched window configuration. Window assemblies have also been modeled and fabricated using compressed window techniques which have proven to increase the power handling capability of waveguide windows. Candidate materials have been chosen to be used in fabricating a window for high power testing at Thomas Jefferson National Accelerator Facility.

MIKE NEUBAUER

2012-11-01T23:59:59.000Z

112

Generation of high intensity rf pulses in the ionosphere by means of in situ compression  

SciTech Connect

We demonstrate, using a simple model, that high intensity pulses can be generated from a frequency-chirped modifier of much lower intensity by making use of the dispersive properties of the ionosphere. We show that a frequency-chirped pulse can be constructed so that its various components overtake each other at a prescribed height, resulting in large (up to one hundred times) transient intensity enhancements as compared to those achievable from a steady modifier operating at the same power. We examine briefly one possible application: the enhancement of plasma wave amplitudes which occurs as a result of the interaction of such a compressed pulse with pre-generated turbulence.

Cowley, S.C.; Perkins, F.W.; Valeo, E.J.

1993-04-01T23:59:59.000Z

113

High-efficiency Resonant rf Spin Rotator with Broad Phase Space Acceptance for Pulsed Polarized Cold Neutron Beams  

SciTech Connect

High precision fundamental neutron physics experiments have been proposed for the intense pulsed spallation neutron beams at JSNS, LANSCE, and SNS to test the standard model and search for new physics. Certain systematic effects in some of these experiments have to be controlled at the few ppb level. The NPD Gamma experiment, a search for the small parity-violating {gamma}-ray asymmetry A{sub Y} in polarized cold neutron capture on parahydrogen, is one example. For the NPD Gamma experiment we developed a radio-frequency resonant spin rotator to reverse the neutron polarization in a 9.5 cm x 9.5 cm pulsed cold neutron beam with high efficiency over a broad cold neutron energy range. The effect of the spin reversal by the rotator on the neutron beam phase space is compared qualitatively to rf neutron spin flippers based on adiabatic fast passage. We discuss the design of the spin rotator and describe two types of transmission-based neutron spin-flip efficiency measurements where the neutron beam was both polarized and analyzed by optically polarized {sup 3}He neutron spin filters. The efficiency of the spin rotator was measured at LANSCE to be 98.8 {+-} 0.5% for neutron energies from 3 to 20 meV over the full phase space of the beam. Systematic effects that the rf spin rotator introduces to the NPD Gamma experiment are considered.

Seo, P. -N. [Los Alamos National Laboratory (LANL); Barron-Palos, L. [Arizona State University; Bowman, J. D. [Los Alamos National Laboratory (LANL); Chupp, T. E. [University of Michigan; Crawford, C. [University of Tennessee, Knoxville (UTK); Dabaghyan, M. [University of New Hampshire; Dawkins, M. [Indiana University; Freedman, S. J. [University of California; Gentile, T. R. [National Institute of Standards and Technology (NIST); Gericke, M. T. [University of Manitoba, Canada; Gillis, R. C. [University of Manitoba, Canada; Greene, G. L. [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL); Hersman, F. W. [University of New Hampshire; Jones, G. L. [Hamilton College, New York; Kandes, M. [University of Michigan; Lamoreaux, S. [Los Alamos National Laboratory (LANL); Lauss, B. [University of California, Berkeley; Leuschner, M. B. [Indiana University; Mahurin, R. [University of Tennessee, Knoxville (UTK); Mason, M. [University of New Hampshire; Mei, J. [Indiana University; Mitchell, G. S. [Los Alamos National Laboratory (LANL); Nann, H. [Indiana University; Page, S. A. [University of Manitoba, Canada; Penttila, S. I. [Los Alamos National Laboratory (LANL); Ramsay, W. D. [University of Manitoba & TRIUMF, Canada; Salas Bacci, A. [Los Alamos National Laboratory (LANL); Santra, S. [Indiana University; Sharma, M. [University of Michigan; Smith, T. B. [University of Dayton, Ohio; Snow, W. [Indiana University; Wilburn, W. S. [Los Alamos National Laboratory (LANL); Zhu, H. [University of New Hampshire

2008-01-01T23:59:59.000Z

114

Brief evaluation of the control and rf systems in the Clinton P. Anderson Meson Physics Facility  

SciTech Connect

- From seminar on high-energy accelerator science; Tokyo and Tsukuba, Japan (5 Nov 1973). The design and operating experience with the computer control system and the rf power systems for the LAMPF linac are outlined. (WHK)

Hagerman, D.C.

1973-01-01T23:59:59.000Z

115

Modulation instability in RF MEMS devices  

Science Conference Proceedings (OSTI)

Modulation instability generated by mechanical frequencies in RF MEMS switches is predicted and its potential contribution to the RF signal degradation is discussed. In particular, evaluations have been performed for double clamped configurations in ... Keywords: Modulation instability, Nonlinear Schrodinger equation, Power handling, RF MEMS

Romolo Marcelli; Giancarlo Bartolucci; Giorgio Angelis; Andrea Lucibello; Emanuela Proietti

2012-04-01T23:59:59.000Z

116

Development of bellows and gate valves with a comb-type rf shield for high-current accelerators: Four-year beam test at KEK B-Factory  

SciTech Connect

Since a comb-type rf shield was proposed in 2003 as a rf shield for future high-intensity accelerators, various types of bellow chambers and gate valves with this rf shield have been installed in the KEK B-Factory rings in series and tested with beams. Through beam tests to check the performance, a structural simplification has been tried in parallel. The temperatures of the bellow corrugations decreased by a factor of 3-6 compared to those with a conventional finger-type rf shield in most cases. The temperatures of the body of the gate valves also decreased by a factor of 2-5. These results demonstrated the availability of the comb-type rf shield. Although a discharge was observed in one simplified model, the latest model has shown no problem up to a stored beam current of 1.8 A (1.3 mA/bunch, 6 mm bunch length). Experiences with the comb-type rf shield in these four-year beam tests are reviewed here.

Suetsugu, Yusuke; Kanazawa, Ken-ichi; Shibata, Kyo; Shirai, Mitsuru; Bondar, Aleksander E.; Kuzminykh, Victor S.; Gorbovsky, Aleksander I.; Sonderegger, Kurt; Morii, Minoru; Kawada, Kakuyu [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Budker Institute of Nuclear Physics (BINP), Novosibirsk 630090 (Russian Federation); VAT Vakuumventile AG, Haag CH-9469 (Switzerland); VAT SKK Vacuum Ltd., Yokohama, Kanagawa 240-0023 (Japan)

2007-04-15T23:59:59.000Z

117

Proton irradiation energy dependence of dc and rf characteristics on InAlN/GaN high electron mobility transistors  

Science Conference Proceedings (OSTI)

The effects of proton irradiation energy on dc and rf characteristics of InAlN/GaN high electron mobility transistors (HEMTs) were investigated. A fixed proton dose of 51015 cm2 with 5, 10, and 15 MeV irradiation energies was used in this study. For the dc characteristics, degradation was observed for sheet resistance, transfer resistance, contact resistivity, saturation drain current, maximum transconductance, reverse-bias gate leakage current, and sub-threshold drain leakage current for all the irradiated HEMTs; however, the degree of the degradation was decreased as the irradiation energy increased. Similar trends were obtained for the rf performance of the devices, with 10% degradation of the unity gain cut-off frequency (fT) and maximum oscillation frequency ( fmax) for the HEMTs irradiated with 15 MeV protons but 30% for 5 MeV proton irradiation. The carrier removal rate was in the range 0.66 1.24 cm1 over the range of proton energies investigated

Lo, C. F. [University of Florida; Liu, L. [University of Florida, Gainesville; Ren, F. [University of Florida; Pearton, S. J. [University of Florida; Gila, Brent P. [University of Florida, Gainesville; Kim, H.-Y. [Korea University; Kim, J. [Korea University; Laboutin, O. [Kopin Corporation, Taunton, MA; Cao, Yu [Kopin Corporation, Taunton, MA; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Kravchenko, Ivan I [ORNL

2012-01-01T23:59:59.000Z

118

High power gas transport laser  

SciTech Connect

Continuous wave output power from a gas transport laser is substantially increased by disposing a plurality of parallel cylindrically tubular cathodes in the main stream transversely of the direction of gas flow and spaced above a coextensive segmented anode in the opposite wall of the channel. Ballast resistors are connected between the cathodes, respectively, and the power supply to optimize the uniform arcless distribution of current passing between each cathode and the anode. Continuous output power greater than 3 kW is achieved with this electrode configuration.

Fahlen, T.S.; Kirk, R.F.

1978-02-28T23:59:59.000Z

119

ISG8-RF Sources  

NLE Websites -- All DOE Office Websites (Extended Search)

RF Sources - (WG3) RF Sources - (WG3) Orange Rm Yong Ho Chin, Christopher Nantista, and Sami G. Tantawi Parallel Sessions: Working Groups: WG1: Parameters, Design, Instrumentation and Tuning WG2: Damping Rings and ATF WG3: RF Sources WG4:Structures WG5: Ground Motion; Site Requirements and Investigations Monday Morning 9:00-10:30 Plenary Coffee Break 11:00-12:00 Planning Session. Monday Afternoon 13:30-15:30 High Gradient Issues (Joint with working group 4) Coffee Break 16:00-16:30 The 8-Pack Project -- D. Atkinson 16:30-17:30 High Gradient Issues and Discussions Continued. Tuesday Morning 9:30-10:30 Klystrons 9:30-10:00 Status of PPM Klystron Development for JLC -- Y. H. Chin 10:00-10:30 Design of 150MW Multi-Beam Klystron -- S. Matsumoto Coffee Break 11:00-11:30 Klystron Development at SLAC -- G. Caryotakis

120

Nanocomposite Alloy Design for High Frequency Power Conversion ...  

Science Conference Proceedings (OSTI)

Presentation Title, Nanocomposite Alloy Design for High Frequency Power ... of power electronic components and systems for power conditioning and grid ...

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

RF transformer  

DOE Patents (OSTI)

There is provided an improved RF transformer having a single-turn secondary of cylindrical shape and a coiled encapsulated primary contained within the secondary. The coil is tapered so that the narrowest separation between the primary and the secondary is at one end of the coil. The encapsulated primary is removable from the secondary so that a variety of different capacity primaries can be utilized with one secondary.

Smith, James L. (Naperville, IL); Helenberg, Harold W. (Calumet City, IL); Kilsdonk, Dennis J. (Joliet, IL)

1979-01-01T23:59:59.000Z

122

High Plains Power Inc | Open Energy Information  

Open Energy Info (EERE)

High Plains Power Inc High Plains Power Inc Place Wyoming Utility Id 8566 Utility Location Yes Ownership C NERC Location WECC NERC WECC Yes Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] Energy Information Administration Form 826[2] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png IRRIGATION Industrial LARGE POWER 500kW OR GREATER TIME OF USE Industrial LARGE POWER DISTRIBUTION SUBSTATION GREATER THAN 500kW LEVEL SERVICE Industrial LARGE POWER DISTRIBUTION SUBSTATION LESS THAN 500kW LEVEL SERVICE Industrial LARGE POWER THREE PHASE DISTRIBUTION PRIMARY LEVEL SERVICE Industrial LARGE POWER THREE PHASE DISTRIBUTION PRIMARY LEVEL SERVICE V2 Industrial

123

Control of the LHC 400 MHz RF System (ACS)  

E-Print Network (OSTI)

The LHC ACS RF system is composed of 16 superconducting cavities, eight per ring. Each ring has two cryomodules, each containing four cavities. Each cavity is powered by a 300 kW klystron. The klystrons are grouped in fours, the klystrons in each group sharing a common 58 kV power converter and HV equipment bunker. The ACS RF control system is based on modern industrial programmable controllers (PLCs). A new fast interlock and alarm system with inbuilt diagnostics has been developed. Extensive use of the FIPIO Fieldbus drastically decreases the cabling complexity and brings improved signal quality, increased reliability and easier maintenance. Features of the implementation, such as system layout, communication and the high-level software interface are described. Operational facilities such as the automatic switch on procedure are described, as well as the necessary specialist tools and interfaces. A complete RF chain, including high voltage, cryomodule and klystron is presently being assembled in order to ch...

Arnaudon, L; Maesen, P; Prax, M

2004-01-01T23:59:59.000Z

124

Loss Mechanisms and High Power Piezoelectric Components - TMS  

Science Conference Proceedings (OSTI)

Oct 15, 2006 ... Loss Mechanisms and High Power Piezoelectric Components ... we demonstrated high power multilayer piezoelectric transformers with Cu or ...

125

500 MW X-Band RF System of a 0.25 GeV Electron LINAC for Advanced Compton Scattering Source Application  

SciTech Connect

A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with the SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

Chu, Tak Sum; /LLNL, Livermore; Anderson, Scott; /LLNL, Livermore; Barty, Christopher; /LLNL, Livermore; Gibson, David; /LLNL, Livermore; Hartemann, Fred; /LLNL, Livermore; Marsh, Roark; /LLNL, Livermore; Siders, Craig; /LLNL, Livermore; Adolphsen, Chris; /SLAC; Jongewaard, Erik; /SLAC; Raubenheimer, Tor; /SLAC; Tantawi, Sami; /SLAC; Vlieks, Arnold; /SLAC; Wang, Juwen; /SLAC

2012-07-03T23:59:59.000Z

126

500 MW X-BAND RF SYSTEM OF A 0.25 GEV ELECTRON LINAC FOR ADVANCED COMPTON SCATTERING SOURCE APPLICATION  

Science Conference Proceedings (OSTI)

A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

Chu, T S; Anderson, S G; Gibson, D J; Hartemann, F V; Marsh, R A; Siders, C; Barty, C P; Adolphsen, C; Jongewaard, E; Tantawi, S; Vlieks, A; Wang, J W; Raubenheimer, T

2010-05-12T23:59:59.000Z

127

Functionalized High Voltage Spinel Composite for High Power ...  

Science Conference Proceedings (OSTI)

Recently, spinel LiNi0.5Mn1.5O4 with high working voltage and long cycle life makes it become the one of most promising cathode for high power delivery.

128

High voltage photovoltaic power converter  

DOE Patents (OSTI)

An array of independently connected photovoltaic cells on a semi-insulating substrate contains reflective coatings between the cells to enhance efficiency. A uniform, flat top laser beam profile is illuminated upon the array to produce electrical current having high voltage. An essentially wireless system includes a laser energy source being fed through optic fiber and cast upon the photovoltaic cell array to prevent stray electrical signals prior to use of the current from the array. Direct bandgap, single crystal semiconductor materials, such as GaAs, are commonly used in the array. Useful applications of the system include locations where high voltages are provided to confined spaces such as in explosive detonation, accelerators, photo cathodes and medical appliances.

Haigh, Ronald E. (Arvada, CO); Wojtczuk, Steve (Cambridge, MA); Jacobson, Gerard F. (Livermore, CA); Hagans, Karla G. (Livermore, CA)

2001-01-01T23:59:59.000Z

129

Use of Coherent Transition Radiation to Set Up the APS RF Thermionic Gun to Produce High-Brightness Beams for SASE FEL Experiments  

E-Print Network (OSTI)

We describe use of the Advanced Photon Source (APS) rf thermionic gun, alpha magnet beamline, and linac to produce a stable high-brightness beam in excess of 100 amperes peak current with normalized emittance of 10 pi mm-mrad. To obtain peak currents greater than 100 amperes, the rf gun system must be tuned to produce a FWHM bunch length on the order of 350 fs. Bunch lengths this short are measured using coherent transition radiation (CTR) produced when the rf gun beam, accelerated to 40 MeV, strikes a metal foil. The CTR is detected using a Golay detector attached to one arm of a Michelson interferometer. The alpha magnet current and gun rf phase are adjusted so as to maximize the CTR signal at the Golay detector, which corresponds to the minimum bunch length. The interferometer is used to measure the autocorrelation of the CTR radiation. The minimum phase approximation is used to derive the bunch profile from the autocorrelation. The high-brightness beam is accelerated to 217 MeV and used to produce SASE in...

Sereno, N S; Lumpkin, Alex H; Sereno, Nicholas; Borland, Michael; Lumpkin, Alex

2000-01-01T23:59:59.000Z

130

USE OF COHERENT TRANSITION RADIATION TO SET UP THE APS RF THERMIONIC GUN TO PRODUCE HIGH-BRIGHTNESS BEAMS FOR SASE FEL EXPERIMENTS ?  

E-Print Network (OSTI)

We describe use of the Advanced Photon Source (APS) rf thermionic gun [1], alpha-magnet beamline, and linac [2] to produce a stable high-brightness beam in excess of 100 amperes peak current with normalized emittance of 10 ? mm-mrad. To obtain peak currents greater than 100 amperes, the rf gun system must be tuned to produce a FWHM bunch length on the order of 350 fs. Bunch lengths this short are measured using coherent transition radiation (CTR) produced when the rf gun beam, accelerated to 40 MeV, strikes a metal foil. The CTR is detected using a Golay detector attached to one arm of a Michelson interferometer. The alpha-magnet current and gun rf phase are adjusted so as to maximize the CTR signal at the Golay detector, which corresponds to the minimum bunch length. The interferometer is used to measure the autocorrelation of the CTR. The minimum phase approximation [3] is used to derive the bunch profile from the autocorrelation. The high-brightness beam is accelerated to 217 MeV and used to produce self-amplified spontaneous emission (SASE) in five APS undulators installed in the Low- Energy Undulator Test Line (LEUTL) experiment hall [4]. Initial optical measurements showed a gain length of 1.3 m at 530 nm. 1

unknown authors

2000-01-01T23:59:59.000Z

131

A high average power pockels cell  

DOE Patents (OSTI)

A high average power pockels cell is disclosed which reduced the effect of thermally induced strains in high average power laser technology. The pockels cell includes an elongated, substantially rectangular crystalline structure formed from a KDP-type material to eliminate shear strains. The X- and Y-axes are oriented substantially perpendicular to the edges of the crystal cross-section and to the C-axis direction of propagation to eliminate shear strains.

Daly, T.P.

1986-02-10T23:59:59.000Z

132

Booster Subharmonic RF Capture Design  

NLE Websites -- All DOE Office Websites (Extended Search)

require a < (1 40 ns) 25 MHz subharmonic frequency. Due to the difficulty of building high-voltage low-frequency rf cavities, this requirement can be relaxed so that at least...

133

Advanced Materials for High Power, High Temperature, and High ...  

Science Conference Proceedings (OSTI)

Mar 5, 2013 ... Advanced magnetic materials are required for enhanced performance of electrical and thermal power generation, distribution, and conversion ...

134

High-availability power for MX  

Science Conference Proceedings (OSTI)

With modern computer-based analyses it was possible to optimize an extensive power transmission and distribution network for supplying power to MX missile shelter sites. This network would serve some 4600 of these sites, located in suitable contiguous areas, with the shelter sites spaced one mile apart. With a dedicated transmission network and underground distribution cables we were able to predict an average commercial power availability of 0.99993 at the shelters. However, standby diesel generator sets are required at distribution centers because power is required after an electromagnetic pulse from a high-altitude weapon burst. With this strengthened distribution network, the authors were able to predict a suitable power availability of 0.999 at each missile site with incoming power supplied to each of our distribution centers at a 0.99 availability or better by local public utilities.

Oman, H.; Bannon, C.F.

1982-08-01T23:59:59.000Z

135

High power regenerative laser amplifier  

DOE Patents (OSTI)

A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse.

Miller, John L. (Livermore, CA); Hackel, Lloyd A. (Livermore, CA); Dane, Clifford B. (Dublin, CA); Zapata, Luis E. (Livermore, CA)

1994-01-01T23:59:59.000Z

136

High power regenerative laser amplifier  

DOE Patents (OSTI)

A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse. 7 figures.

Miller, J.L.; Hackel, L.A.; Dane, C.B.; Zapata, L.E.

1994-02-08T23:59:59.000Z

137

Multi-band high efficiency power amplifier  

E-Print Network (OSTI)

that the transistor is disabled, the remaining part of theby conducting current, or disabled. Since the RF transistorLikewise, when the diode is disabled, the diode will ideally

Besprozvanny, Randy-Alexander Randolph

2011-01-01T23:59:59.000Z

138

High-resolution laser and rf spectroscopy of atomic and molecular beams  

Science Conference Proceedings (OSTI)

Most of the effort during the past year has been applied to continuing our systematic study of the hyperfine (hfs) and spin-rotation interactions in the calcium monohalide family of radicals. The work is now about 75% complete. The systematic, high-precision measurements will ultimately enable theorists to test the quality of wave functions obtained in ab initio calculations of the structure of these small molecules. Progress is described. (WHK)

Childs, W.J.; Cok, D.R.; Goodman, L.S.

1982-01-01T23:59:59.000Z

139

Experimental evaluation of 350 MHz RF accelerator windows for the low energy demonstration accelerator  

SciTech Connect

Radio frequency (RF) windows are historically a point where failure occurs in input power couplers for accelerators. To obtain a reliable, high-power, 350 MHz RF window for the Low Energy Demonstration Accelerator (LEDA) project of the Accelerator Production of Tritium program, RF windows prototypes from different vendors were tested. Experiments were performed to evaluate the RF windows by the vendors to select a window for the LEDA project. The Communications and Power, Inc. (CPI) windows were conditioned to 445 kW in roughly 15 hours. At 445 kW a window failed, and the cause of the failure will be presented. The English Electronic Valve, Inc. (EEV) windows were conditioned to 944 kW in 26 hours and then tested at 944 kW for 4 hours with no indication of problems.

Cummings, K.; Rees, D.; Roybal, W. [and others

1997-09-01T23:59:59.000Z

140

Progress on the RF Coupling Coil Module Design for the MICE Channel  

E-Print Network (OSTI)

Spallation Neutron Source (SNS) type ceramic RF windows arecouplers together with the SNS-type ceramic RF window. Ahigh power tested now at the SNS RF test lab. Cavity length

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

The NASA CSTI High Capacity Power Project  

SciTech Connect

The SP-100 Space Nuclear Power Program was established in 1983 by DOD, DOE, and NASA as a joint program to develop technology for military and civil applications. Starting in 1986, NASA has funded a technology program to maintain the momentum of promising aerospace technology advancement started during Phase I of SP-100 and to strengthen, in key areas, the changes for successful development and growth capability of space nuclear reactor power systems for a wide range of future space applications. The elements of the CSTI High Capacity Power Project include Systems Analysis, Stirling Power Conversion, Thermoelectric Power Conversion, Thermal Management, Power Management, Systems Diagnostics, Environmental Interactions, and Material/Structural Development. Technology advancement in all elements is required to provide the growth capability, high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall project with develop and demonstrate the technology base required to provide a wide range of modular power systems compatible with the SP-100 reactor which facilitates operation during lunar and planetary day/night cycles as well as allowing spacecraft operation at any attitude or distance from the sun. Significant accomplishments in all of the project elements will be presented, along with revised goals and project timelines recently developed.

Winter, J.; Dudenhoefer, J.; Juhasz, A.; Schwarze, G.; Patterson, R.; Ferguson, D.; Titran, R. [National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center; Schmitz, P. [Sverdrup Technology, Inc., Brook Park, OH (United States). Lewis Research Center Group; Vandersande, J. [Jet Propulsion Lab., Pasadena, CA (United States)

1994-09-01T23:59:59.000Z

142

rf_shield.PDF  

NLE Websites -- All DOE Office Websites (Extended Search)

April 2001 Interaction Region RF Shield Issues G. Stupakov and T.O. Raubenheimer Stanford Linear Accelerator Center Stanford, California 102300 Interaction Region RF Shield...

143

HIGH AVERAGE POWER OPTICAL FEL AMPLIFIERS.  

SciTech Connect

Historically, the first demonstration of the optical FEL was in an amplifier configuration at Stanford University [l]. There were other notable instances of amplifying a seed laser, such as the LLNL PALADIN amplifier [2] and the BNL ATF High-Gain Harmonic Generation FEL [3]. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance FEL's with average power of 100 kW or more. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting Energy Recovery Linacs (ERL) combine well with the high-gain FEL amplifier to produce unprecedented average power FELs. This combination has a number of advantages. In particular, we show that for a given FEL power, an FEL amplifier can introduce lower energy spread in the beam as compared to a traditional oscillator. This properly gives the ERL based FEL amplifier a great wall-plug to optical power efficiency advantage. The optics for an amplifier is simple and compact. In addition to the general features of the high average power FEL amplifier, we will look at a 100 kW class FEL amplifier is being designed to operate on the 0.5 ampere Energy Recovery Linac which is under construction at Brookhaven National Laboratory's Collider-Accelerator Department.

BEN-ZVI, ILAN, DAYRAN, D.; LITVINENKO, V.

2005-08-21T23:59:59.000Z

144

Magnetic Materials for High Frequency Power Electronics  

Science Conference Proceedings (OSTI)

Mar 7, 2013 ... Advanced Materials for Power Electronics, Power Conditioning, and Power ... in power conditioning, conversion, and generation applications.

145

Ultra high vacuum broad band high power microwave window  

DOE Patents (OSTI)

An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost.

Nguyen-Tuong, Viet (Seaford, VA); Dylla, III, Henry Frederick (Yorktown, VA)

1997-01-01T23:59:59.000Z

146

Ultra high vacuum broad band high power microwave window  

DOE Patents (OSTI)

An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost. 5 figs.

Nguyen-Tuong, V.; Dylla, H.F. III

1997-11-04T23:59:59.000Z

147

Spectroscopy of {sup 257}Rf.  

Science Conference Proceedings (OSTI)

The isotope {sup 257}Rf was produced in the fusion-evaporation reaction {sup 208}Pb({sup 50}Ti,n){sup 257}Rf. Reaction products were separated and identified by mass. Delayed spectroscopy of {sup 257}Rf and its decay products was performed. A partial decay scheme with configuration assignments is proposed based on hindrance factors. The excitation energy of the 1/2{sup +}[620] configuration in {sup 253}No is proposed. The energy of this 1/2{sup +} state in a series of N=151 isotones increases with nuclear charge, reflecting an increase in the N=152 gap. This gap is deduced to grow substantially from 850 to 1400 keV between Z=94 and 102. An isomeric state in {sup 257}Rf, with a half-life of 160{sub -31}{sup +42} {micro}s, was discovered by detecting internal conversion electrons followed by decay. It is interpreted as a three-quasiparticle high-K isomer. A second group of internal conversion electrons, with a half-life of 4.1{sub -1.3}{sup +2.4} s, followed by decay, was also observed. These events might originate from the decay of excited states in {sup 257}Lr, populated by electron-capture decay of {sup 257}Rf. Fission of {sup 257}Rf was unambiguously detected, with a branching ratio of b{sub Rf}{sup SF} = 0.02 {+-} 0.01.

Qian, J.; Heinz, A.; Khoo, T. L.; Janssens, R. V. F.; Peterson, D.; Seweryniak, D.; Ahmad, I.; Asai, M.; Back, B. B.; Carpenter, M. P.; Garnsworthy, A. B.; Greene, J. P.; Hecht, A. A.; Jiang, C. L.; Kondev, F. G.; Lauritsen, T.; Lister, C. J.; Robinson, A.; Savard, G.; Scott, R.; Vondrasek, R.; Wang, X.; Winkler, R.; Zhu, S.; Yale Univ.; Japan Atomic Energy Agency; Univ. of Surrey; Univ. of Maryland

2009-06-01T23:59:59.000Z

148

Spectroscopy of {sup 257}Rf  

Science Conference Proceedings (OSTI)

The isotope {sup 257}Rf was produced in the fusion-evaporation reaction {sup 208}Pb({sup 50}Ti,n){sup 257}Rf. Reaction products were separated and identified by mass. Delayed spectroscopy of {sup 257}Rf and its decay products was performed. A partial decay scheme with configuration assignments is proposed based on {alpha} hindrance factors. The excitation energy of the 1/2{sup +}[620] configuration in {sup 253}No is proposed. The energy of this 1/2{sup +} state in a series of N=151 isotones increases with nuclear charge, reflecting an increase in the N=152 gap. This gap is deduced to grow substantially from 850 to 1400 keV between Z=94 and 102. An isomeric state in {sup 257}Rf, with a half-life of 160{sub -31}{sup +42} {mu}s, was discovered by detecting internal conversion electrons followed by {alpha} decay. It is interpreted as a three-quasiparticle high-K isomer. A second group of internal conversion electrons, with a half-life of 4.1{sub -1.3}{sup +2.4} s, followed by {alpha} decay, was also observed. These events might originate from the decay of excited states in {sup 257}Lr, populated by electron-capture decay of {sup 257}Rf. Fission of {sup 257}Rf was unambiguously detected, with a branching ratio of b{sub Rf}{sup SF}=0.02{+-}0.01.

Qian, J.; Heinz, A.; Winkler, R. [WNSL, Yale University, New Haven, Connecticut 06511 (United States); Khoo, T. L.; Janssens, R. V. F.; Peterson, D.; Seweryniak, D.; Ahmad, I.; Back, B. B.; Carpenter, M. P.; Greene, J. P.; Jiang, C. L.; Kondev, F. G.; Lauritsen, T.; Lister, C. J.; Robinson, A.; Savard, G.; Scott, R.; Vondrasek, R.; Wang, X. [Argonne National Laboratory, Illinois 60439 (United States)] (and others)

2009-06-15T23:59:59.000Z

149

ATF2 High Availability Power Supplies  

SciTech Connect

ATF2 is an accelerator test facility modeled after the final focus beamline envisioned for the ILC. By the end of 2008, KEK plans to commission the ATF2 [1]. SLAC and OCEM collaborated on the design of 38 power systems for beamline magnets. The systems range in output power from 1.5 kW to 6 kW. Since high availability is essential for the success of the ILC, Collaborators employed an N+1 modular approach, allowing for redundancy and the use of a single power module rating. This approach increases the availability of the power systems. Common power modules reduces inventory and eases maintenance. Current stability requirements are as tight as 10 ppm. A novel, SLAC designed 20-bit Ethernet Power Supply Controller provides the required precision current regulation. In this paper, Collaborators present the power system design, the expected reliability, fault immunity features, and the methods for satisfying the control and monitoring challenges. Presented are test results and the status of the power systems.

Bellomo, A; Lira, C.de; Lam, B.; MacNair, D.; White, G.; /SLAC

2008-06-27T23:59:59.000Z

150

Technology development for high power induction accelerators  

SciTech Connect

The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability.

Birx, D.L.; Reginato, L.L.

1985-06-11T23:59:59.000Z

151

Architecture for ultra-low power multi-channel transmitters for Body Area Networks using RF resonators  

E-Print Network (OSTI)

Body Area Networks (BANs) are gaining prominence for their use in medical and sports monitoring. This thesis develops the specifications of a ultra-low power 2.4GHz transmitter for use in a Body Area Networks, taking ...

Paidimarri, Arun

2011-01-01T23:59:59.000Z

152

Characterization of high-power RF structures using time-domain field codes  

Science Conference Proceedings (OSTI)

We have modeled gyrotron windows and gyrotron amplifier sever structures for TE modes in the 100--150 GHz range and have computed the reflection and transmission characteristics from the field data. Good agreement with frequency domain codes and analytic analysis have been obtained for some simple geometries. We present results for realistic structures with lossy coatings and describe implementation of microwave diagnostics.

Shang, C.C.; DeFord, J.F.; Swatloski, T.L.

1992-08-21T23:59:59.000Z

153

RF Gun Photocathode Research at SLAC  

Science Conference Proceedings (OSTI)

LCLS is presently operating with a third copper photocathode in the original rf gun, with a quantum efficiency (QE) of {approx}1 x 10{sup -4} and projected emittance {gamma}{var_epsilon}{sub x,y} = 0.45 {micro}m at 250 pC bunch charge. The spare LCLS gun is installed in the SLAC Accelerator Structure Test Area (ASTA), fully processed to high rf power. As part of a wider photocathode R and D program, a UV laser system and additional gun diagnostics are being installed at ASTA to measure QE, QE lifetime, and electron beam emittance under a variety of operating conditions. The near-term goals are to test and verify the spare photocathode production/installation sequence, including transfer from the final holding chamber to the rf gun. Mid- and longer-term goals include development of a rigorous understanding of plasma and laser-assisted surface conditioning and investigation of new, high-QE photocathode materials. In parallel, an x-ray photoemission spectroscopy station is nearing completion, to analyze Cu photocathode surface chemistry. In this paper we review the status and anticipated operating parameters of ASTA and the spectroscopy test chamber.

Jongewaard, E.; Akre, R.; Brachmann, A.; Corbett, J.; Gilevich, S.; Grouev, K.; Hering, P.; P.Krejcik,; Lewandowski, J.; Loos, H.; Montagne, T.; Sheppard, J.C.; Stefan, P.; Vlieks, A.; Weathersby, S.; Zhou, F.; /SLAC

2012-05-16T23:59:59.000Z

154

CHALLENGES FACING HIGH POWER PROTON ACCELERATORS  

Science Conference Proceedings (OSTI)

This presentation will provide an overview of the challenges of high power proton accelerators such as SNS, J-PARC, etc., and what we have learned from recent experiences. Beam loss mechanisms and methods to mitigate beam loss will also be discussed.

Plum, Michael A [ORNL

2013-01-01T23:59:59.000Z

155

Multi-band high efficiency power amplifier  

E-Print Network (OSTI)

Baseline) Output Power (Transformer) Drain Efficiency (Performance Frequency (GHz) Output Power (Transformer) DrainEfficiency (Transformer) Output Power (Baseline) Drain

Besprozvanny, Randy-Alexander Randolph

2011-01-01T23:59:59.000Z

156

Low Cost High Concentration PV Systems for Utility Power Generation...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Other Agencies You are here Home Low Cost High Concentration PV Systems for Utility Power Generation Low Cost High Concentration PV Systems for Utility Power Generation An...

157

Low Cost High Concentration PV Systems for Utility Power Generation...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Other Agencies You are here Home Low Cost High Concentration PV Systems for Utility Power Generation Amonix, Inc. Low Cost High Concentration PV Systems for Utility Power...

158

Rf phase measurement at PHERMEX (Pulsed High Energy Radiographic Machine Emitting X-Rays) using time-to-digital converters  

Science Conference Proceedings (OSTI)

Recent advances in time-to-digital converters (TDCs) have made 50-MHz rf phase measurement possible without the use of double-balanced mixers. These advances allow zero crossing discriminators to be used in conjunction with fast CAMAC TDCs to make amplitude-independent phase measurements. This method uses a time interval proportional to the phase angle, thus eliminating any of the calculations and calibration required with double-balanced mixers. 4 refs., 1 fig., 1 tab.

Watson, S.A.; Jennings, G.R.; Moir, D.C.

1989-01-01T23:59:59.000Z

159

Time dependant quantum efficiency and dark current measurements in an RF photocathode injector with a high quantum efficiency cathode  

SciTech Connect

Studies of photo-emission and field emission behavior in an RF gun have been carried out. Unexpected phenomena were observed. In situ changes in the cathode's quantum efficiency and dark current with time were seen during operation of the photo-injector. These changes were correlated with the magnetostatic field at the cathode. In addition, multipacting has been observed under certain conditions. Recent measurements indicate a correlation between multipacting and anomalous photo- and field emission behavior.

Fliller, R.P., III; Edwards, H.; /Fermilab; Hartung, W.; /Michigan State U., NSCL

2005-05-01T23:59:59.000Z

160

High Power UV LED Industrial Curing Systems  

Science Conference Proceedings (OSTI)

UV curing is a green technology that is largely underutilized because UV radiation sources like Hg Lamps are unreliable and difficult to use. High Power UV LEDs are now efficient enough to replace Hg Lamps, and offer significantly improved performance relative to Hg Lamps. In this study, a modular, scalable high power UV LED curing system was designed and tested, performing well in industrial coating evaluations. In order to achieve mechanical form factors similar to commercial Hg Lamp systems, a new patent pending design was employed enabling high irradiance at long working distances. While high power UV LEDs are currently only available at longer UVA wavelengths, rapid progress on UVC LEDs and the development of new formulations designed specifically for use with UV LED sources will converge to drive more rapid adoption of UV curing technology. An assessment of the environmental impact of replacing Hg Lamp systems with UV LED systems was performed. Since UV curing is used in only a small portion of the industrial printing, painting and coating markets, the ease of use of UV LED systems should increase the use of UV curing technology. Even a small penetration of the significant number of industrial applications still using oven curing and drying will lead to significant reductions in energy consumption and reductions in the emission of green house gases and solvent emissions.

Karlicek, Robert, F., Jr; Sargent, Robert

2012-05-14T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Closed-cell 201.25 MHz RF structures for a muon cooling channel  

DOE Green Energy (OSTI)

We report on the research and development of high gradient low frequency closed-cell structures for possible use in a muon cooling channel. The presence of strong magnetic fields precludes the use of superconducting RF. These multi-cell structures have the ''beam iris'' closed by conducting oils, grids of tubes or other isolating structures. This greatly increases the shunt impedance and also allows the individually powered cells to be set independently to any phase. The isolating structure must be made using a very small amount of low-Z material to avoid unacceptable scattering of the muon beam. Various cell designs and methods of closure are presented and compared. The problems of RF heating and breakdown at high gradient are discussed with regard to the vulnerable isolating structures. RF, thermal and stress analyses are presented and the integration of the RF with the solenoid cryostat and liquid hydrogen absorbers is considered.

Rimmer, R.; Hartman, N.; Ladran, A.; Li, D.; Moretti, A.; Jurgens, T.

2001-06-01T23:59:59.000Z

162

high impact Designing a human-powered  

E-Print Network (OSTI)

to the local mill and pay to have it ground into flour, or grind it themselves by hand with a mortar and pestleLow tech, high impact Designing a human-powered grain mill for Africa Ten-year-old Solomoni Mafuta) to a diesel-pow- ered mill to be ground. The time-consuming task has pulled him away from his studies

Endres. William J.

163

Review of the APS SR RF systems.  

DOE Green Energy (OSTI)

The Advanced Photon Source (APS) is a 7-GeV full energy storage ring (SR) for generating synchrotron radiation with an injector. The storage ring cavities consist of four groups of four single cells powered by up to four 1-MW klystrons for up to 300-mA operation. A review of the operation of the rf system as well as rf-related beam dynamics is presented. This review includes rf power distribution, low-level feedback, control law, beam loading, beam instabilities, higher-order modes, and beam-induced multipactoring.

Song, J.J.; Cours, A.; Grelick, A.; Harkay, K.; Horan, D.; Kang, Y.W.; Kustom, R.L.; Nassiri, A.; Pile, G.; Smith, T.L.

1998-03-31T23:59:59.000Z

164

Production of high power femtosecond terahertz radiation  

SciTech Connect

The terahertz (THz) region of the electromagnetic spectrum is attracting interest for a broad range of applications ranging from diagnosing electron beams to biological imaging. Most sources of short pulse THz radiation utilize excitation of biased semiconductors or electro-optic crystals by high peak power lasers. For example, this was done by using an un-doped InAs wafer irradiated by a femtosecond free-electron laser (FEL) at the Thomas Jefferson National Accelerator Facility. Microwatt levels of THz radiation were detected when excited with FEL pulses at 1.06 mm wavelength and 10W average power. Recently substantially higher powers of femtosecond THz pulses produced by synchrotron emission were extracted from the electron beamline. Calculations and measurements confirm the production of coherent broadband THz radiation from relativistic electrons with an average power of nearly 20W, a world record in this wavelength range by a factor of 10,000. We describe the source, presenting theoretical calculations and their experimental verification. Potential applications of this exciting new source include driving new non-linear phenomena, performing pump-probe studies of dynamical properties of novel materials, and studying molecular vibrations and rotations, low frequency protein motions, phonons, superconductor band gaps, electronic scattering, collective electronic excitations (e.g., charge density waves), and spintronics.

Neil, George R.; Carr, G.L.; Gubeli III, Joseph F.; Jordan, K.; Martin, Michael C.; McKinney, Wayne R.; Shinn, Michelle; Tani, Masahiko; Williams, G.P.; Zhang, X.-C.

2003-07-11T23:59:59.000Z

165

Decay Study of {sup 257}Rf  

Science Conference Proceedings (OSTI)

The isotope {sup 257}Rf was produced in the fusion-evaporation reaction {sup 208}Pb({sup 50}Ti, n){sup 257}Rf. Reaction products were separated by the Argonne Fragment Mass Analyzer. Radioactive decay and spontaneous fission of {sup 257}Rf and its decay products were investigated. An isomeric state in {sup 257}Rf, with a half-life of 160{sub -31}{sup 42} {mu}S, was discovered by detecting internal conversion electrons followed by alpha decays. It is interpreted as a three-quasiparticle high-K isomer. A second group of internal-conversion electrons which were succeeded by alpha decay, with a half-life of 4.1{sub -1.3}{sup +2.4} s, was observed. These events might originate from the decay of excited states in {sup 257}Lr, populated by electron-capture decay of {sup 257}Rf, or from another isomer in {sup 257}Rf.

Qian, J.; Heinz, A.; Winkler, R. [Yale University, New Haven, CT 06511 (United States); Janssens, R. V. F.; Khoo, T. L.; Seweryniak, D.; Peterson, D.; Back, B. B.; Carpenter, M. P.; Greene, J. P.; Jiang, C. L.; Kondev, F. G.; Lauritsen, T.; Lister, C. J.; Pardo, R. C.; Robinson, A.; Scott, R.; Vondrasek, R.; Wang, X.; Zhu, S. [Argonne National Laboratory, Argonne, IL 60439 (United States)] (and others)

2009-03-04T23:59:59.000Z

166

High average power CW FELs (Free Electron Laser) for application to plasma heating: Designs and experiments  

SciTech Connect

A short period wiggler (period {approximately} 1 cm), sheet beam FEL has been proposed as a low-cost source of high average power (1 MW) millimeter-wave radiation for plasma heating and space-based radar applications. Recent calculation and experiments have confirmed the feasibility of this concept in such critical areas as rf wall heating, intercepted beam ( body'') current, and high voltage (0.5 - 1 MV) sheet beam generation and propagation. Results of preliminary low-gain sheet beam FEL oscillator experiments using a field emission diode and pulse line accelerator have verified that lasing occurs at the predicted FEL frequency. Measured start oscillation currents also appear consistent with theoretical estimates. Finally, we consider the possibilities of using a short-period, superconducting planar wiggler for improved beam confinement, as well as access to the high gain, strong pump Compton regime with its potential for highly efficient FEL operation.

Booske, J.H.; Granatstein, V.L.; Radack, D.J.; Antonsen, T.M. Jr.; Bidwell, S.; Carmel, Y.; Destler, W.W.; Latham, P.E.; Levush, B.; Mayergoyz, I.D.; Zhang, Z.X. (Maryland Univ., College Park, MD (USA). Lab. for Plasma Research); Freund, H.P. (Science Applications International Corp., McLean, VA (USA))

1989-01-01T23:59:59.000Z

167

High Performance Wide Bandgap Power Electronics  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and ... therefore, designers unknowingly navigate the design space with a lack of ...

168

Digitally Controlled High Availability Power Supply  

SciTech Connect

This paper reports the design and test results on novel topology, high-efficiency, and low operating temperature, 1,320-watt power modules for high availability power supplies. The modules permit parallel operation for N+1 redundancy with hot swap capability. An embedded DSP provides intelligent start-up and shutdown, output regulation, general control and fault detection. PWM modules in the DSP drive the FET switches at 20 to 100 kHz. The DSP also ensures current sharing between modules, synchronized switching, and soft start up for hot swapping. The module voltage and current have dedicated ADCs (>200 kS/sec) to provide pulse-by-pulse output control. A Dual CAN bus interface provides for low cost redundant control paths. Over-rated module components provide high reliability and high efficiency at full load. Low on-resistance FETs replace conventional diodes in the buck regulator. Saturable inductors limit the FET reverse diode current during switching. The modules operate in a two-quadrant mode, allowing bipolar output from complimentary module groups. Controllable, low resistance FETs at the input and output provide fault isolation and allow module hot swapping.

MacNair, David; /SLAC

2008-09-25T23:59:59.000Z

169

Design of RF systems for the RTD mission VASIMR  

SciTech Connect

The first flight test of the variable specific impulse magnetoplasma rocket (VASIMR) is tentatively scheduled for the Radiation and Technology Demonstration (RTD) in 2003. This mission to map the radiation environment out to several earth radii will employ both a Hall thruster and a VASIMR during its six months duration, beginning from low earth orbit. The mission will be powered by a solar array providing 12 kW of direct current electricity at 50 V. The VASIMR utilizes radiofrequency (RF) power both to generate a high-density plasma in a helicon source and to accelerate the plasma ions to high velocity by ion cyclotron resonance heating (ICRH). The VASIMR concept is being developed by the National Aeronautics and Space Administration (NASA) in collaboration with national laboratories and universities. Prototype plasma sources, RF amplifiers, and antennas are being developed in the experimental facilities of the Advanced Space Propulsion Laboratory (ASPL). (c) 1999 American Institute of Physics.

Baity, F. W. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Barber, G. C. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Carter, M. D. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Goulding, R. H. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Sparks, D. O. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Chang-Diaz, F. R. [Advanced Space Propulsion Laboratory, NASA, Johnson Space Center, Houston, Texas 77059 (United States); McCaskill, G. E. [Advanced Space Propulsion Laboratory, NASA, Johnson Space Center, Houston, Texas 77059 (United States); Squire, J. P. [Advanced Space Propulsion Laboratory, NASA, Johnson Space Center, Houston, Texas 77059 (United States)

1999-09-20T23:59:59.000Z

170

Design of RF Systems for the RTD Mission VASIMR  

SciTech Connect

The first flight test of the variable specific impulse magnetoplasma rocket (VASIMR) is tentatively scheduled for the Radiation and Technology Demonstration (RTD) in 2003. This mission to map the radiation environment out to several earth radii will employ both a Hall thruster and a VASIMR during its six months duration, beginning from low earth orbit. The mission will be powered by a solar array providing 12 kW of direct current electricity at 50 V. The VASIMR utilizes radiofrequency (RF) power both to generate a high-density plasma in a helicon source and to accelerate the plasma ions to high velocity by ion cyclotron resonance heating (ICRH). The VASIMR concept is being developed by the National Aeronautics and Space Administration (NASA) in collaboration with national laboratories and universities. Prototype plasma sources, RF amplifiers, and antennas are being developed in the experimental facilities of the Advanced Space Propulsion Laboratory (ASPL).

Baity, F.W.; Barber, G.C.; Carter, M.D.; Chang-Diaz, F.R.; Goulding, R.H.; McCaskill, G.E.; Sparks, D.O.; Squire, J.P.

1999-04-12T23:59:59.000Z

171

The JLab high power ERL light source  

DOE Green Energy (OSTI)

A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz {approx} half cycle pulse whose average brightness is > 5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted[1]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [2]: up to 10 kW of average power in the IR from 1 to 14 microns in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300-1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 microseconds long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the system and discuss some of the discoveries we have made concerning the physics performance, design optimization, and operational limitations of such a first generation high power ERL light source.

G.R. Neil; C. Behre; S.V. Benson; M. Bevins; G. Biallas; J. Boyce; J. Coleman; L.A. Dillon-Townes; D. Douglas; H.F. Dylla; R. Evans; A. Grippo; D. Gruber; J. Gubeli; D. Hardy; C. Hernandez-Garcia; K. Jordan; M.J. Kelley; L. Merminga; J. Mammosser; W. Moore; N. Nishimori; E. Pozdeyev; J. Preble; R. Rimmer; Michelle D. Shinn; T. Siggins; C. Tennant; R. Walker; G.P. Williams and S. Zhang

2005-03-19T23:59:59.000Z

172

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.

Stamps, James Frederick (Livermore, CA); Crocker, Robert Ward (Fremont, CA); Yee, Daniel Dadwa (Dublin, CA); Dils, David Wright (Fort Worth, TX)

2006-03-14T23:59:59.000Z

173

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.

Stamps, James Frederick (Livermore, CA); Crocker, Robert Ward (Fremont, CA); Yee, Daniel Dadwa (Dublin, CA); Dils, David Wright (Fort Worth, TX)

2008-03-25T23:59:59.000Z

174

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Power Coherent Terahertz Radiation Laser Seeding Yields High-Power Coherent Terahertz Radiation Print Wednesday, 25 April 2007 00:00 Researchers at Berkeley Lab have been exploring...

175

LEDA - A HIGH-POWER TEST BED OF INNOVATION AND OPPORTUNITY  

Science Conference Proceedings (OSTI)

The low-energy demonstration accelerator (LEDA) is an operational 6.7-MeV. 100-mA proton accelerator consisting of an injector, radio-frequency quadrupole (RFQ), and all associated integration equipment. In order to achieve this unprecedented level of performance (670-kW of beam power) from an RFQ, a number of design innovations were required. They will highlight a number of those more significant technical advances, including those in the proton injector, the RFQ configuration, the RF klystrons, the beam stop, and the challenges of beam measurements. In addition to identifying the importance of these innovations to LEDA performance, they will summarize the plans for further testing, and the possibilities for addition of more accelerating structures, including the planned use of very-low-beta super-conducting structures. LEDA's current and upgradable configuration is appropriate for several future high-power accelerators, including those for the transmutation of radioactive waste.

J. SCHNEIDER; R. SHEFFIELD

2000-08-01T23:59:59.000Z

176

High power radio frequency attenuation device  

DOE Patents (OSTI)

A resistor device for attenuating radio frequency power includes a radio frequency conductor connected to a series of fins formed of high relative magnetic permeability material. The fins are dimensional to accommodate the skin depth of the current conduction therethrough, as well as an inner heat conducting portion where current does not travel. Thermal connections for air or water cooling are provided for the inner heat conducting portions of each fin. Also disclosed is a resistor device to selectively alternate unwanted radio frequency energy in a resonant cavity.

Kerns, Quentin A. (Bloomingdale, IL); Miller, Harold W. (Winfield, IL)

1984-01-01T23:59:59.000Z

177

High-temperature alloys for high-power thermionic systems  

DOE Green Energy (OSTI)

The need for structural materials with useful strength above 1600 k has stimulated interest in refractory-metal alloys. Tungsten possesses an extreme high modulus of elasticity as well as the highest melting temperature among metals, and hence is being considered as one of the most promising candidate materials for high temperature structural applications such as space nuclear power systems. This report is divided into three chapters covering the following: (1) the processing of tungsten base alloys; (2) the tensile properties of tungsten base alloys; and (3) creep behavior of tungsten base alloys. Separate abstracts were prepared for each chapter. (SC)

Shin, Kwang S.; Jacobson, D.L.; D'cruz, L.; Luo, Anhua; Chen, Bor-Ling.

1990-08-01T23:59:59.000Z

178

Wind energy and power system interconnection, control, and operation for high penetration of wind power .  

E-Print Network (OSTI)

??High penetration of wind energy requires innovations in different areas of power engineering. Methods for improving wind energy and power system interconnection, control, and operation… (more)

Liang, Jiaqi

2012-01-01T23:59:59.000Z

179

Digitally Controlled High Availability Power Supply  

SciTech Connect

This paper will report on the test results of a prototype 1320 watt power module for a high availability power supply. The module will allow parallel operation for N+1 redundancy with hot swap capability. The two quadrant output of each module allows pairs of modules to provide a 4 quadrant (bipolar) operation. Each module employs a novel 4 FET buck regulator arranged in a bridge configuration. Each side of the bridge alternately conducts through a small saturable ferrite that limits the reverse current in the FET body diode during turn off. This allows hard switching of the FETs with low switching losses. The module is designed with over-rated components to provide high reliability and better then 97% efficiency at full load. The modules use a Microchip DSP for control, monitoring, and fault detection. The switching FETS are driven by PWM modules in the DSP at 60 KHz. A Dual CAN bus interface provides for low cost redundant control paths. The DSP will also provide current sharing between modules, synchronized switching, and soft start up for hot swapping. The input and output of each module have low resistance FETs to allow hot swapping and isolation of faulted units.

MacNair, David; /SLAC

2009-05-07T23:59:59.000Z

180

Power excursion analysis for high burnup cores  

SciTech Connect

A study was undertaken of power excursions in high burnup cores. There were three objectives in this study. One was to identify boiling water reactor (BWR) and pressurized water reactor (PWR) transients in which there is significant energy deposition in the fuel. Another was to analyze the response of BWRs to the rod drop accident (RDA) and other transients in which there is a power excursion. The last objective was to investigate the sources of uncertainty in the RDA analysis. In a boiling water reactor, the events identified as having significant energy deposition in the fuel were a rod drop accident, a recirculation flow control failure, and the overpressure events; in a pressurized water reactor, they were a rod ejection accident and boron dilution events. The RDA analysis was done with RAMONA-4B, a computer code that models the space- dependent neutron kinetics throughout the core along with the thermal hydraulics in the core, vessel, and steamline. The results showed that the calculated maximum fuel enthalpy in high burnup fuel will be affected by core design, initial conditions, and modeling assumptions. The important uncertainties in each of these categories are discussed in the report.

Diamond, D.J.; Neymotin, L.; Kohut, P. [Brookhaven National Lab., Upton, NY (United States)

1996-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

High output lamp with high brightness  

DOE Patents (OSTI)

An ultra bright, low wattage inductively coupled electrodeless aperture lamp is powered by a solid state RF source in the range of several tens to several hundreds of watts at various frequencies in the range of 400 to 900 MHz. Numerous novel lamp circuits and components are disclosed including a wedding ring shaped coil having one axial and one radial lead, a high accuracy capacitor stack, a high thermal conductivity aperture cup and various other aperture bulb configurations, a coaxial capacitor arrangement, and an integrated coil and capacitor assembly. Numerous novel RF circuits are also disclosed including a high power oscillator circuit with reduced complexity resonant pole configuration, parallel RF power FET transistors with soft gate switching, a continuously variable frequency tuning circuit, a six port directional coupler, an impedance switching RF source, and an RF source with controlled frequency-load characteristics. Numerous novel RF control methods are disclosed including controlled adjustment of the operating frequency to find a resonant frequency and reduce reflected RF power, controlled switching of an impedance switched lamp system, active power control and active gate bias control.

Kirkpatrick, Douglas A. (Great Falls, VA); Bass, Gary K. (Mt. Airy, MD); Copsey, Jesse F. (Germantown, MD); Garber, Jr., William E. (Poolesville, MD); Kwong, Vincent H. (Vancouver, CA); Levin, Izrail (Silver Spring, MD); MacLennan, Donald A. (Gaithersburg, MD); Roy, Robert J. (Frederick, MD); Steiner, Paul E. (Olney, MD); Tsai, Peter (Olney, MD); Turner, Brian P. (Damascus, MD)

2002-01-01T23:59:59.000Z

182

Matching network for RF plasma source  

DOE Patents (OSTI)

A compact matching network couples an RF power supply to an RF antenna in a plasma generator. The simple and compact impedance matching network matches the plasma load to the impedance of a coaxial transmission line and the output impedance of an RF amplifier at radio frequencies. The matching network is formed of a resonantly tuned circuit formed of a variable capacitor and an inductor in a series resonance configuration, and a ferrite core transformer coupled to the resonantly tuned circuit. This matching network is compact enough to fit in existing compact focused ion beam systems.

Pickard, Daniel S. (Palo Alto, CA); Leung, Ka-Ngo (Hercules, CA)

2007-11-20T23:59:59.000Z

183

Water Cooling of High Power Light Emitting Diode Henrik Srensen  

E-Print Network (OSTI)

Water Cooling of High Power Light Emitting Diode Henrik Sørensen Department of Energy Technology and product lifetime. The high power Light Emitting Diodes (LED) belongs to the group of electronics

Sørensen, Henrik

184

Improved Collectors for High Power Gyrotrons  

Science Conference Proceedings (OSTI)

High power gyrotrons are used for electron cyclotron heating, current drive and parasitic mode suppression in tokamaks for fusion energy research. These devices are crucial for successful operation of many research programs around the world, including the ITER program currently being constructed in France. Recent gyrotron failures resulted from cyclic fatigue of the copper material used to fabricated the collectors. The techniques used to collect the spent beam power is common in many gyrotrons produced around the world. There is serious concern that these tubes may also be at risk from cyclic fatigue. This program addresses the cause of the collector failure. The Phase I program successfully demonstrated feasibility of a mode of operation that eliminates the cyclic operation that caused the failure. It also demonstrated that new material can provide increased lifetime under cyclic operation that could increase the lifetime by more than on order of magnitude. The Phase II program will complete that research and develop a collector that eliminates the fatigue failures. Such a design would find application around the world.

R. Lawrence Ives, Amarjit Singh, Michael Read, Philipp Borchard, Jeff Neilson

2009-05-20T23:59:59.000Z

185

Rf Feedback free electron laser  

DOE Patents (OSTI)

A free electron laser system and electron beam system for a free electron laser which use rf feedback to enhance efficiency. Rf energy is extracted from an electron beam by decelerating cavities and returned to accelerating cavities using rf returns such as rf waveguides, rf feedthroughs, etc. This rf energy is added to rf klystron energy to lower the required input energy and thereby enhance energy efficiency of the system.

Brau, Charles A. (Los Alamos, NM); Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM)

1981-01-01T23:59:59.000Z

186

Rf feedback free electron laser  

DOE Patents (OSTI)

A free electron laser system and electron beam system for a free electron laser are provided which use rf feedback to enhance efficiency. Rf energy is extracted from an electron beam by decelerating cavities and returned to accelerating cavities using rf returns such as rf waveguides, rf feedthroughs, etc. This rf energy is added to rf klystron energy to lower the required input energy and thereby enhance energy efficiency of the system.

Brau, C.A.; Swenson, D.A.; Boyd, T.J. Jr.

1979-11-02T23:59:59.000Z

187

2008 High-Megawatt Power Converter Technology R&D ...  

Science Conference Proceedings (OSTI)

... 2008 High-Megawatt Power Converter Technology R&D Roadmap Workshop. NIST, Gaithersburg, MD. April 8, 2008. On ...

2013-05-30T23:59:59.000Z

188

Vortex formation during rf heating of plasma  

SciTech Connect

Experiments on a test plasma show that the linear theory of waveguide coupling to slow plasma waves begins to break down if the rf power flux exceeds approx. 30 W/cm/sup 2/. Probe measurements reveal that within 30 ..mu..s an undulation appears in the surface plasma near the mouth of the twin waveguide. This surface readjustment is part of a vortex, or off-center convective cell, driven by asymmetric rf heating of the plasma column.

Motley, R.W.

1980-05-01T23:59:59.000Z

189

Piezoelectric based high voltage power simulator for implantation  

Science Conference Proceedings (OSTI)

It is based on resonant method that allows the piezoelectric transformer to generate a ... The device is small and with high power density and high efficiency

190

Solid-State High Voltage Modulator and Its Application to RF Source High Voltage Power Supplies (A26129)  

E-Print Network (OSTI)

Proc. Of 25th Symposium On Fusion Technology, Rostock, Germany, 2008, To Be Published25th Symposium on Fusion Technology Rostock, DE, 2008999615250

Tooker, J.F.

2008-07-11T23:59:59.000Z

191

High power linear pulsed beam annealer  

DOE Patents (OSTI)

A high power pulsed electron beam is produced in a system comprised of an electron gun having a heated cathode, control grid, focus ring, and a curved drift tube. The drift tube is maintained at a high positive voltage with respect to the cathode to accelerate electrons passing through the focus ring and to thereby eliminate space charge. A coil surrounding the curved drift tube provides a magnetic field which maintains the electron beam focused about the axis of the tube and imparts motion on electrons in a spiral path for shallow penetration of the electrons into a target. The curvature of the tube is selected so there is no line of sight between the cathode and a target holder positioned within a second drift tube spaced coaxially from the curved tube. The second tube and the target holder are maintained at a reference voltage that decelerates the electrons. A second coil surrounding the second drift tube maintains the electron beam focused about the axis of the second drift tube and compresses the electron beam to the area of the target. The target holder can be adjusted to position the target where the cross section of the beam matches the area of the target.

Strathman, Michael D. (Concord, CA); Sadana, Devendra K. (Berkeley, CA); True, Richard B. (Sunnyvale, CA)

1983-01-01T23:59:59.000Z

192

Radiolysis with RF Photoinjectors  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiolysis with RF Photoinjectors: Supercritical Xenon Chemistry James F. Wishart in "Femtosecond Beam Science" Uesaka, M., Ed.; Imperial College Press, London, in press. (ISBN...

193

FERROELECTRIC SWITCH FOR A HIGH-POWER Ka-BAND ACTIVE PULSE COMPRESSOR  

Science Conference Proceedings (OSTI)

Results are presented for design of a high-power microwave switch for operation at 34.3 GHz, intended for use in an active RF pulse compressor. The active element in the switch is a ring of ferroelectric material, whose dielectric constant can be rapidly changed by application of a high-voltage pulse. As envisioned, two of these switches would be built into a pair of delay lines, as in SLED-II at SLAC, so as to allow 30-MW ?s-length Ka-band pulses to be compressed in time by a factor-of-9 and multiplied in amplitude to generate 200 MW peak power pulses. Such high-power pulses could be used for testing and evaluation of high-gradient mm-wave accelerator structures, for example. Evaluation of the switch design was carried out with an X-band (11.43 GHz) prototype, built to incorporate all the features required for the Ka-band version.

Hirshfield, Jay L. [Omega-P, Inc.

2013-12-18T23:59:59.000Z

194

A SUMMARY OF TEST OBSERVATIONS WHEN IBUTTONS ARE SUBJECTED TO RF ENERGY  

SciTech Connect

The iButton is a 'one-wire', temperature sensor and data logger in a short metal cylinder package 17 mm in diameter and 6 mm tall. The device is designed to be attached to a surface and acquire temperature samples over time periods as short as 1 second to as long as 300 minutes. Both 8-bit and 16-bit samples are available with 8kB of memory available. Lifetime is limited to an internal battery that cannot be replaced or recharged. The RF test interest originated with the concern that the data logger could inadvertently record electrical emanations from other nearby equipment. The normal operation of the data logger does not support high speed sampling but the control interface will operate at either 15.4 kbps or 125 kbps. There were no observable effects in the operation of the module or in the data that could be attributed to the use of RF energy. They made the assumption that these devices would potentially show RF sensitivity in any of the registers and in the data memory equally, therefore gross changes in the data might show RF susceptibility. No such sensitivity was observed. Because significant power levels were used for these tests they can extrapolate downward in power to state that no RF susceptibility would occur at lower power levels given the same configurations.

Kane, R J; Baluyot, E V

2011-10-26T23:59:59.000Z

195

Rf System for the NLCTA  

Science Conference Proceedings (OSTI)

This paper describes an X-Band RF system for the Next Linear Collider Test Accelerator. The RF system consists of a 90 MeV injector and a 540 MeV linac. The main components of the injector are two low-Q single-cavity prebunchers and two 0.9-m-long detuned accelerator sections. The linac system consists of six 1.8-m-long detuned and damped detuned accelerator sections powered in pairs. The rf power generation, compression, delivery, distribution and measurement systems consist of klystrons, SLEDII energy compression systems, rectangular waveguides, magic-T's, and directional couplers. The phase and amplitude for each prebuncher is adjusted via a magic-T type phase shifter/attenuator. Correct phasing between the two 0.9 m accelerator sections is obtained by properly aligning the sections and adjusting two squeeze type phase shifters. Bunch phase and bunch length can be monitored with special microwave cavities and measurement systems. The design, fabrication, microwave measurement, calibration, and operation of the sub-systems and their components are briefly presented.

Wang, J.W.; /SLAC; Adolphsen, C.; Eichner, J.; Fuller, R.W.; Gold, S.L.; Hanna, S.M.; Hoag, H.A.; Holmes, S.G.; Koontz, R.F.; Lavine, Theodore L.; Loewen, R.J.; Miller, R.H.; Nantista, C.D.; Pope, R.; Rifkin, J.; Ruth, R.D.; Tantawi, S.G.; Vlieks, A.E.; Wilson, Z.; Yeremian, A.; /SLAC

2011-08-26T23:59:59.000Z

196

High power densities from high-temperature material interactions  

DOE Green Energy (OSTI)

Thermionic energy conversion (TEC) and metallic-fluid heat pipes (MFHPs) offer important and unique advantages in terrestrial and space energy processing. And they are well suited to serve together synergistically. TEC and MFHPs operate through working-fluid vaporization, condensation cycles that accept great thermal power densities at high temperatures. TEC and MFHPs have apparently simple, isolated performance mechanisms that are somewhat similar. And they also have obviously difficult, complected material problems that again are somewhat similar. Intensive investigation reveals that aspects of their operating cycles and material problems tend to merge: high-temperature material effects determine the level and lifetime of performance. Simplified equations verify the preceding statement for TEC and MFHPs. Material properties and interactions exert primary influences on operational effectiveness. And thermophysicochemical stabilities dictate operating temperatures which regulate the thermoemissive currents of TEC and the vaporization flow rates of MFHPs. Major high-temperature material problems of TEC and MFHPs have been solved. These solutions lead to productive, cost-effective applications of current TEC and MFHPs - and point to significant improvements with anticipated technological gains.

Morris, J.F.

1981-01-01T23:59:59.000Z

197

High voltage VLF testing of power cables  

SciTech Connect

This publication describes a laboratory test program conducted with the objective to develop a test that would replace the existing dc withstand test. The article describes the methodology used to establish the voltage duration and magnitude of VLF (0.1 Hz) high voltage field tests suitable for crosslinked polyethylene (XLPE) insulated power cable. The results show that the voltage breakdown of laboratory aged XLPE cable at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz cause very little damage to the cable, and that 0.1 Hz testing appears to be a satisfactory alternate to dc testing. Preliminary values are suggested for voltage magnitude and time duration of cable acceptance, maintenance and proof tests at 0.1 Hz for XLPE cable rated up to 35 kV. A program is underway to similarly evaluate samples of service-aged XLPE cable; as well as to demonstrate the use of the preliminary test values at typical utility installations.

Eager, G.S.; Katz, C.; Fryszczyn, B. [Cable Technology Labs., Inc., New Brunswick, NJ (United States); Densley, J. [Ontario Hydro, Toronto, Ontario (Canada); Bernstein, B.S. [EPRI, Washington, DC (United States)

1997-04-01T23:59:59.000Z

198

Nuclear power high technology colloquium: proceedings  

Science Conference Proceedings (OSTI)

Reports presenting information on technology advancements in the nuclear industry and nuclear power plant functions have been abstracted and are available on the energy data base.

Not Available

1984-12-10T23:59:59.000Z

199

RF Choke for Standing Wave Structures and Flanges  

DOE Green Energy (OSTI)

SLAC participates in the U.S. High Gradient collaboration whose charter includes basic studies of rf breakdown properties in accelerating structures. These studies include experiments with different materials and construction methods for single cell standing wave accelerating structures. The most commonly used method of joining cells of such structures is the high temperature bonding and/or brazing in hydrogen and/or vacuum. These high temperature processes may not be suitable for some of the new materials that are under consideration. We propose to build structures from cells with an rf choke, taking the cell-to-cell junction out of the electromagnetic field region. These cells may be clamped together in a vacuum enclosure, the choke joint ensuring continuity of rf currents. Next, we propose a structure with a choke joint in a high gradient cell and a view port which may allow us microscopic, in-situ observation of the metal surface during high power tests. And third, we describe the design of a TM01 choke flange for these structures.

Yeremian, Anahid; /SLAC; Dolgashev, Valery; /SLAC; Tantawi, Sami; /SLAC

2012-07-03T23:59:59.000Z

200

High-power semiconductor separate-confinement double heterostructure lasers  

Science Conference Proceedings (OSTI)

The review is devoted to high-power semiconductor lasers. Historical reference is presented, physical and technological foundations are considered, and the concept of high-power semiconductor lasers is formulated. Fundamental and technological reasons limiting the optical power of a semiconductor laser are determined. The results of investigations of cw and pulsed high-power semiconductor lasers are presented. Main attention is paid to inspection of the results of experimental studies of single high-power semiconductor lasers. The review is mainly based on the data obtained in the laboratory of semiconductor luminescence and injection emitters at the A.F. Ioffe Physicotechnical Institute. (review)

Tarasov, I S [A.F. Ioffe Physical-Technical Institute, Russian Academy of Sciences, St. Petersburg (Russian Federation)

2010-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Research on Control System of High Power DFIG Wind Power System  

Science Conference Proceedings (OSTI)

Compared with constant speed constant frequency wind turbine, variable speed constant frequency wind turbine has many advantages: higher efficiency of wind energy converting to electric power, absorbing gust energy, smoothly cutting into the network ... Keywords: wind power, DFIG, high power, LQR, variable speed constant frequency, constant power control

Li Jianlin; Xu Honghua

2008-12-01T23:59:59.000Z

202

Techniques for high-efficiency outphasing power amplifiers  

E-Print Network (OSTI)

A trade-off between linearity and efficiency exists in conventional power amplifiers (PAs). The outphase amplifying concept overcomes this trade-off by enabling the use of high efficiency, non-linear power amplifiers for ...

Godoy, Philip (Philip Andrew)

2011-01-01T23:59:59.000Z

203

Quasi-optical mode converter for high power gyrotron  

Science Conference Proceedings (OSTI)

Gyrotrons are microwave / millimeter wave devices capable to deliver megawatt level continuous power at a frequency range up to 170GHz. The critical design issues for a high power gyrotrons are: (1) Magnetron injection Gun (2) Cavity with proper mode ...

B. K. Shukla; Dhiraj Bora

2011-02-01T23:59:59.000Z

204

Innovative fuel designs for high power density pressurized water reactor  

E-Print Network (OSTI)

One of the ways to lower the cost of nuclear energy is to increase the power density of the reactor core. Features of fuel design that enhance the potential for high power density are derived based on characteristics of ...

Feng, Dandong, Ph. D. Massachusetts Institute of Technology

2006-01-01T23:59:59.000Z

205

Design of annular fuel for high power density BWRs  

E-Print Network (OSTI)

Enabling high power density in the core of Boiling Water Reactors (BWRs) is economically profitable for existing or new reactors. In this work, we examine the potential for increasing the power density in BWR plants by ...

Morra, Paolo

2005-01-01T23:59:59.000Z

206

Simulation of RF Cavity Dark Current In Presence of Helical Magnetic Field  

Science Conference Proceedings (OSTI)

In order to produce muon beam of high enough quality to be used for a Muon Collider, its large phase space must be cooled several orders of magnitude. This task can be accomplished by ionization cooling. Ionization cooling consists of passing a high-emittance muon beam alternately through regions of low Z material, such as liquid hydrogen, and very high accelerating RF cavities within a multi-Tesla solenoidal focusing channel. But first high power tests of RF cavity with beryllium windows in solenoidal magnetic field showed a dramatic drop in accelerating gradient due to RF breakdowns. It has been concluded that external magnetic fields parallel to RF electric field significantly modifies the performance of RF cavities. However, magnetic field in Helical Cooling Channel has a strong dipole component in addition to solenoidal one. The dipole component essentially changes electron motion in a cavity compare to pure solenoidal case, making dark current less focused at field emission sites. The simulation of dark current dynamic in HCC performed with CST Studio Suit is presented in this paper.

Romanov, Gennady; Kashikhin, Vladimir; /Fermilab

2012-05-01T23:59:59.000Z

207

High power millimeter wave experiment of ITER relevant electron cyclotron heating and current drive system  

Science Conference Proceedings (OSTI)

High power, long pulse millimeter (mm) wave experiments of the RF test stand (RFTS) of Japan Atomic Energy Agency (JAEA) were performed. The system consists of a 1 MW/170 GHz gyrotron, a long and short distance transmission line (TL), and an equatorial launcher (EL) mock-up. The RFTS has an ITER-relevant configuration, i.e., consisted by a 1 MW-170 GHz gyrotron, a mm wave TL, and an EL mock-up. The TL is composed of a matching optics unit, evacuated circular corrugated waveguides, 6-miter bends, an in-line waveguide switch, and an isolation valve. The EL-mock-up is fabricated according to the current design of the ITER launcher. The Gaussian-like beam radiation with the steering capability of 20 deg. - 40 deg. from the EL mock-up was also successfully proved. The high power, long pulse power transmission test was conducted with the metallic load replaced by the EL mock-up, and the transmission of 1 MW/800 s and 0.5 MW/1000 s was successfully demonstrated with no arcing and no damages. The transmission efficiency of the TL was 96%. The results prove the feasibility of the ITER electron cyclotron heating and current drive system.

Takahashi, K.; Kajiwara, K.; Oda, Y.; Kasugai, A.; Kobayashi, N.; Sakamoto, K. [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Doane, J.; Olstad, R. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Henderson, M. [ITER Organization, CS90 046, 13067 St. Paul lez Durance Cedex (France)

2011-06-15T23:59:59.000Z

208

Phase stable rf transport system  

DOE Patents (OSTI)

This invention is comprised of an RF transport system which delivers a phase-stable RF signal to a load, such as an RF cavity of a charged particle accelerator. A circuit generates a calibration signal at an odd multiple frequency of the RF signal where the calibration signal is superimposed with the RF signal on a common cable that connects the RF signal with the load. Signal isolating diplexers are located at both the RF signal source end and load end of the common cable to enable the calibration to be inserted and extracted from the cable signals without any affect on the RF signal. Any phase shift in the calibration signal during traverse of the common cable is then functionally related to the phase shift in the RF signal. The calibration phase shift is used to control a phase shifter for the RF signal to maintain a stable RF signal at the load.

Curtin, M.T.; Natter, E.F.; Denney, P.M.

1991-02-19T23:59:59.000Z

209

Phase stable RF transport system  

DOE Patents (OSTI)

An RF transport system delivers a phase-stable RF signal to a load, such as an RF cavity of a charged particle accelerator. A circuit generates a calibration signal at an odd multiple frequency of the RF signal where the calibration signal is superimposed with the RF signal on a common cable that connects the RF signal with the load. Signal isolating diplexers are located at both the RF signal source end and load end of the common cable to enable the calibration to be inserted and extracted from the cable signals without any affect on the RF signal. Any phase shift in the calibration signal during traverse of the common cable is then functionally related to the phase shift in the RF signal. The calibration phase shift is used to control a phase shifter for the RF signal to maintain a stable RF signal at the load.

Curtin, Michael T. (Los Alamos, NM); Natter, Eckard F. (San Francisco, CA); Denney, Peter M. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

210

Low Loss, High Power Density Magnetics in Inductor/Transformer ...  

Science Conference Proceedings (OSTI)

The former power requirements motivate high efficiency materials for use in bulk scale inductors and transformers. The magnetic material requirements include ...

211

High Temperature Modules and Materials for Thermoelectric Power ...  

Science Conference Proceedings (OSTI)

We fabricated oxide-based thermoelectric modules for high temperature electrical-power generation. Potentials for a development of a thermoelectric generation ...

212

High Power Performance Lithium Ion Battery - Energy Innovation Portal  

... “Optimization of Acetylene Black Conductive Additive and Polyvinylidene Fluoride Composition for high Power Rechargeable Lithium-Ion Cells,” The 211th ...

213

Device Fabrication Method for High Power Density Capacitors  

Device Fabrication Method for High Power Density Capacitors Note: The technology described above is an early stage opportunity. Licensing rights to this intellectual ...

214

Diagnostics and steady-state high power operation  

Science Conference Proceedings (OSTI)

TORE SUPRA has now been upgraded to handle high power plasmas for very long duration. It came back into operation in 2001

Clément Laviron; and the Tore Supra Team

2003-01-01T23:59:59.000Z

215

Available Technologies: High Power Performance Lithium Ion Battery  

Cell 1, which has the highest binder (PVDF) to acetylene black ratio, displays the most favorable discharge ASI. Lithium ion batteries with high power ...

216

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Laser Seeding Yields High-Power Coherent Terahertz Radiation Print Researchers at Berkeley Lab have been exploring the ways coherent synchrotron radiation (CSR) is generated in...

217

High power semiconductor laser diode arrays  

SciTech Connect

The cw optical power obtainable from semiconductor laser diodes has been extended to unprecedented levels in recent years through the use of multistripe arrays. By spreading out the optical power with more than 100 stripes, single-facet, cw output in exces of 5 Watts has been demonstrated, and 500 mW cw is now commercially available. Recent improvements to array performance include: arrays up to 1 cm wide that generates quasi-cw (150 usec pulse) output in excesss of 11 Watts, and a novel device structure which produces up to 215 mW cw in a single diffraction limited lobe.

Cross, P.S.

1986-08-15T23:59:59.000Z

218

E-beam high voltage switching power supply  

DOE Patents (OSTI)

A high-power power supply produces a controllable, constant high voltage put under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1996-01-01T23:59:59.000Z

219

E-beam high voltage switching power supply  

DOE Patents (OSTI)

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules. 5 figs.

Shimer, D.W.; Lange, A.C.

1996-10-15T23:59:59.000Z

220

Interaction of high power microwave with plasma  

Science Conference Proceedings (OSTI)

An experimental proposal to investigate the physics of interaction of extremely intense (eEem/m?c ? 1) microwave in an overdense plasma is discussed. The output from a VIRCATOR (2 -- 10 GHz, ? 1 -- 3 GW) based pulse (?30 ns) powered ...

V. P. Anitha; Amita Das; Y. C. Saxena; Anurag Shyam; P. K. Kaw

2011-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

High Power Lasers... Another approach to  

E-Print Network (OSTI)

Research Laboratory Washington, DC #12;2 Main points of the talk Fusion Energy based on lasers and direct employees, (900 PhDs + 400 MSc) · $800 M /year budget ·Field sites: · Washington DC (Main site) · Stennis (Hibachi) Amplifier Window Electron Beam Cathode Pulsed Power System Energy + ( Kr+ F2) ( KrF)* + F Kr

222

High-power LED driver with power-efficient LED-current-sensing technique.  

E-Print Network (OSTI)

??x, 73 leaves : ill. ; 30 cm HKUST Call Number: Thesis ECED 2007 LeungW To provide enough light output for various lighting applications, high-power… (more)

Leung, Wing Yan

2007-01-01T23:59:59.000Z

223

Self-homodyne RF-optical microdisk receiver  

E-Print Network (OSTI)

modulation with optical transfer function (Po VRF 2 ) Self-homodyne RF-photonic receiver f ip Nonlinear and nonlinear modulation Transmittedoptical power t Wavelength t t Linear (Po VRF) Nonlinear (Po VRF 2) VRF ),,,,,( , 0 2 0 2 2 tPQGf dV Pd N EinoV VRF RF == = Microdisk optical mixer (laser= res) GV : voltage gain Q

Levi, Anthony F. J.

224

New Concepts For High Power ICRF Antennas  

Science Conference Proceedings (OSTI)

This paper presents new concepts for Ion Cyclotron Heating antennas based on cascaded sequences of tuned radiating structures. It is shown that, in large arrays, such as the ones proposed for fusion reactors applications, these schemes offer, in principle, a number of desirable features, such as operation at power density significantly higher than currently adopted systems, at equal maximum voltage and array geometry, simple mechanical layout, suitable for water cooling, a compact impedance tuning system, passive decoupling of the array elements, single ended or balanced feed from two power sources. The antenna layout also allows the remote, real time measurement of the complex impedance of the radiating elements and the detection, location, and measurement of the complex admittance of arcs occurring anywhere in the structure, as discussed in [1].

Bosia, G. [Department of Physics University of Turin (Italy)

2011-12-23T23:59:59.000Z

225

Realization and modeling of rf superconducting quantum interference device metamaterials  

E-Print Network (OSTI)

We have prepared meta-atoms based on radio frequency superconducting quantum interference devices (RF SQUIDs) and examined their tunability with dc magnetic field, rf current, and temperature. RF SQUIDs are superconducting split ring resonators in which the usual capacitance is supplemented with a Josephson junction, which introduces strong nonlinearity in the rf properties. We find excellent agreement between the data and a model which regards the Josephson junction as the resistively and capacitively-shunted junction. A magnetic field tunability of 80 THz/Gauss at 12 GHz is observed, a total tunability of 56$%$ is achieved, and a unique electromagnetically-induced transparency feature at intermediate excitation powers is demonstrated for the first time. An RF SQUID metamaterial is shown to have qualitatively the same behavior as a single RF SQUID with regards to DC flux and temperature tuning.

M. Trepanier; Daimeng Zhang; Oleg Mukhanov; Steven M. Anlage

2013-08-06T23:59:59.000Z

226

High performance low power CMOS dynamic logic for arithmetic circuits  

Science Conference Proceedings (OSTI)

This paper presents the design of high performance and low power arithmetic circuits using a new CMOS dynamic logic family, and analyzes its sensitivity against technology parameters for practical applications. The proposed dynamic logic family allows ... Keywords: CMOS digital integrated circuits, CMOS logic circuits, Dynamic logic, High speed arithmetic circuits, Low power arithmetic circuits

Victor Navarro-Botello; Juan A. Montiel-Nelson; Saeid Nooshabadi

2007-04-01T23:59:59.000Z

227

SLAC Linac RF Performance for LCLS *  

E-Print Network (OSTI)

The Linac Coherent Light Source (LCLS) project at SLAC uses a dense 15 GeV electron beam passing through a long undulator to generate extremely bright x-rays at 1.5 angstroms. The project requires electron bunches with a nominal peak current of 3.5kA and bunch lengths of 0.020mm (70fs). The bunch compression techniques used to achieve the high brightness impose challenging tolerances on the accelerator RF phase and amplitude. The results of measurements on the existing SLAC linac RF phase and amplitude stability are summarised and improvements needed to meet the LCLS tolerances are discussed. 1 LCLS RF REQUIREMENTS LCLS requires the SLAC linac to perform with tolerances on RF phase and amplitude stability which are beyond all previous requirements. The LCLS is divided into four linacs L0, L1, L2, and L3 [1]. The phase and amplitude tolerances for the four linacs operated at S-

unknown authors

2000-01-01T23:59:59.000Z

228

1.3 GHz superconducting RF cavity program at Fermilab  

SciTech Connect

At Fermilab, 9-cell 1.3 GHz superconducting RF (SRF) cavities are prepared, qualified, and assembled into cryomodules (CMs) for Project X, an International Linear Collider (ILC), or other future projects. The 1.3 GHz SRF cavity program includes targeted R&D on 1-cell 1.3 GHz cavities for cavity performance improvement. Production cavity qualification includes cavity inspection, surface processing, clean assembly, and one or more cryogenic low-power CW qualification tests which typically include performance diagnostics. Qualified cavities are welded into helium vessels and are cryogenically tested with pulsed high-power. Well performing cavities are assembled into cryomodules for pulsed high-power testing in a cryomodule test facility, and possible installation into a beamline. The overall goals of the 1.3 GHz SRF cavity program, supporting facilities, and accomplishments are described.

Ginsburg, C.M.; Arkan, T.; Barbanotti, S.; Carter, H.; Champion, M.; Cooley, L.; Cooper, C.; Foley, M.; Ge, M.; Grimm, C.; Harms, E.; /Fermilab

2011-03-01T23:59:59.000Z

229

A finite-difference time-domain simulation of high power microwave generated plasma at atmospheric pressures  

Science Conference Proceedings (OSTI)

A finite-difference algorithm was developed to calculate several RF breakdown parameters, for example, the formative delay time that is observed between the initial application of a RF field to a dielectric surface and the formation of field-induced plasma interrupting the RF power flow. The analysis is focused on the surface being exposed to a background gas pressure above 50 Torr. The finite-difference algorithm provides numerical solutions to partial differential equations with high resolution in the time domain, making it suitable for simulating the time evolving interaction of microwaves with plasma; in lieu of direct particle tracking, a macroscopic electron density is used to model growth and transport. This approach is presented as an alternative to particle-in-cell methods due to its low complexity and runtime leading to more efficient analysis for a simulation of a microsecond scale pulse. The effect and development of the plasma is modeled in the simulation using scaling laws for ionization rates, momentum transfer collision rates, and diffusion coefficients, as a function of electric field, gas type and pressure. The incorporation of plasma material into the simulation involves using the Z-transform to derive a time-domain algorithm from the complex frequency-dependent permittivity of plasma. Therefore, the effect of the developing plasma on the instantaneous microwave field is calculated. Simulation results are compared with power measurements using an apparatus designed to facilitate surface flashover across a polycarbonate boundary in a controlled N{sub 2}, air, or argon environment at pressures exceeding 50 Torr.

Ford, Patrick J.; Beeson, Sterling R.; Krompholz, Hermann G.; Neuber, Andreas A. [Department of Electrical and Computer Engineering, Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, Texas 79409-3102 (United States)

2012-07-15T23:59:59.000Z

230

SOLAR POWERING OF HIGH EFFICIENCY ABSORPTION CHILLER  

SciTech Connect

This is the Final Report for two solar cooling projects under this Cooperative Agreement. The first solar cooling project is a roof-integrated solar cooling and heating system, called the Power Roof{trademark}, which began operation in Raleigh, North Carolina in late July 2002. This system provides 176 kW (50 ton) of solar-driven space cooling using a unique nonimaging concentrating solar collector. The measured performance of the system during its first months of operation is reported here, along with a description of the design and operation of this system. The second solar cooling system, with a 20-ton capacity, is being retrofit to a commercial office building in Charleston, South Carolina but has not yet been completed.

Randy C. Gee

2004-11-15T23:59:59.000Z

231

Modular high voltage power supply for chemical analysis  

DOE Patents (OSTI)

A high voltage power supply for use in a system such as a microfluidics system, uses a DC-DC converter in parallel with a voltage-controlled resistor. A feedback circuit provides a control signal for the DC-DC converter and voltage-controlled resistor so as to regulate the output voltage of the high voltage power supply, as well as, to sink or source current from the high voltage supply.

Stamps, James F. (Livermore, CA); Yee, Daniel D. (Dublin, CA)

2008-07-15T23:59:59.000Z

232

Modular high voltage power supply for chemical analysis  

DOE Patents (OSTI)

A high voltage power supply for use in a system such as a microfluidics system, uses a DC--DC converter in parallel with a voltage-controlled resistor. A feedback circuit provides a control signal for the DC--DC converter and voltage-controlled resistor so as to regulate the output voltage of the high voltage power supply, as well as, to sink or source current from the high voltage supply.

Stamps, James F. (Livermore, CA); Yee, Daniel D. (Dublin, CA)

2007-01-09T23:59:59.000Z

233

Improved Spatial Filter for high power Lasers  

DOE Patents (OSTI)

A new pinhole architecture incorporates features intended to reduce the rate of plasma generation in a spatial filter for high-energy laser pulse beams. An elongated pinhole aperture is provided in an apertured body for rejecting off-axis rays of the laser pulse beam. The internal surface of the elongated aperture has a diameter which progressively tapers from a larger entrance cross-sectional area at an inlet to a smaller output cross-sectional area at an outlet. The tapered internal surface causes off-axis rays to be refracted in a low density plasma layer that forms on the internal surface or specularly reflected at grazing incidence from the internal surface. Off-axis rays of the high-energy pulse beam are rejected by this design. The external surface of the apertured body adjacent to the larger entrance cross-sectional area at the inlet to the elongated aperture is angled obliquely with respect to the to direction of the path of the high-energy laser pulse beam to backscatter off-axis rays away from the high-energy pulse beam. The aperture is formed as a truncated cone or alternatively with a tapered square cross-section. The internal surface of the aperture is coated with an ablative material, preferably high-density material which can be deposited with an exploding wire.

Estabrook, Kent G.; Celliers, Peter M.; Murray, James E.; DaSilva, Luiz; MacGowan, Brian J.; Rubenchik, Alexander M.; Manes, Kenneth R.; Drake, Robert P.; Afeyan, Bedros

1998-06-01T23:59:59.000Z

234

GaN High Power Devices  

SciTech Connect

A brief review is given of recent progress in fabrication of high voltage GaN and AlGaN rectifiers, GaN/AlGaN heterojunction bipolar transistors, GaN heterostructure and metal-oxide semiconductor field effect transistors. Improvements in epitaxial layer quality and in fabrication techniques have led to significant advances in device performance.

PEARTON,S.J.; REN,F.; ZHANG,A.P.; DANG,G.; CAO,X.A.; LEE,K.P.; CHO,H.; GILA,B.P.; JOHNSON,J.W.; MONIER,C.; ABERNATHY,C.R.; HAN,JUNG; BACA,ALBERT G.; CHYI,J.-I.; LEE,C.-M.; NEE,T.-E.; CHUO,C.-C.; CHI,G.C.; CHU,S.N.G.

2000-07-17T23:59:59.000Z

235

Method and apparatus for tuning high power lasers  

DOE Patents (OSTI)

This invention relates to high power gas lasers that are adapted to be tuned to a desired lasing wavelength through the use of a gas cell to lower the gain at a natural lasing wavelength and "seeding" the laser with a beam from a low power laser which is lasing at the desired wavelength. This tuning is accomplished with no loss of power and produces a pulse with an altered pulse shape. It is potentially applicable to all gas lasers.

Hutchinson, Donald P. (Knoxville, TN); Vandersluis, Kenneth L. (Oak Ridge, TN)

1977-04-19T23:59:59.000Z

236

Angle Instability Detection in Power Systems with High Wind Penetration  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Angle Instability Detection in Power Angle Instability Detection in Power Systems with High Wind Penetration Using PMUs YC Zhang National Renewable Energy Laboratory Yingchen.zhang@nrel.gov 27/28 June 2013 Washington, DC DOE/OE Transmission Reliability Program Angle Instability Detection in Power Systems with High Wind Penetration Using Synchrophasor Measurements  Project Objective * Utilize synchrophasor measurements to estimate the equivalent inertia of a power source such as synchronous generators or wind turbine generators * Develop angle instability detection method for a system with high wind penetration using the synchrophasor measurements 2 3 Background Submitted to IEEE Journal of Emerging and Selected Topics in Power Electronics * In case of angular instability, some machines will have

237

Symbolic Reduction for High-Speed Power System Simulation  

Science Conference Proceedings (OSTI)

High-speed simulations of power transmission systems, which often rely on solving nonlinear systems of equations, are an increasingly important tool for training, testing equipment, on-line control and situational awareness. Such simulations, however, ... Keywords: Code generation, power system simulation, real-time systems, sparse systems, symbolic and algebraic manipulation

William M. Siever; Daniel R. Tauritz; Ann Miller; Mariesa Crow; Bruce M. Mcmillin; Stanley Atcitty

2008-06-01T23:59:59.000Z

238

Rf2a and rf2b transcription factors  

DOE Patents (OSTI)

A method of activating the rice tungro bacilliform virus (RTBV) promoter in vivo is disclosed. The RTBV promoter is activated by exposure to at least one protein selected from the group consisting of Rf2a and Rf2b.

Beachy, Roger N. (St. Louis, MO); Petruccelli, Silvana (La Plata, AR); Dai, Shunhong (St. Louis, MO)

2007-10-02T23:59:59.000Z

239

High Plains Ranch Solar Power Plant | Open Energy Information  

Open Energy Info (EERE)

High Plains Ranch Solar Power Plant High Plains Ranch Solar Power Plant Jump to: navigation, search Name High Plains Ranch Solar Power Plant Facility High Plains Ranch Sector Solar Facility Type Photovoltaic Developer Sun Power Location Carizzo Plain, California Coordinates 35.1913858°, -119.7260983° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":35.1913858,"lon":-119.7260983,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

240

High-voltage DC transmission: a power electronics workhorse  

Science Conference Proceedings (OSTI)

Thyristor-based HVDC converter technology is used for highly reliable power transfer across natural or national boundaries or between AC systems designed for different frequencies or incompatible frequency controls. The author discusses the benefits ...

N. G. Hingorani

1996-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

High Power Superconducting Continuous Wave Linacs for Protons...  

Office of Science (SC) Website

(ANL) Developed in: Current Result of NP research: Spin-off of high power driver linac R&D for the FRIB project Application currently being supported by: DOE Office of Nuclear...

242

High Specific Power, Direct Methanol Fuel Cell Stack  

NLE Websites -- All DOE Office Websites (Extended Search)

High Specific Power, Direct Methanol Fuel Cell Stack High Specific Power, Direct Methanol Fuel Cell Stack High Specific Power, Direct Methanol Fuel Cell Stack The present invention is a fuel cell stack including at least one direct methanol fuel cell. Available for thumbnail of Feynman Center (505) 665-9090 Email High Specific Power, Direct Methanol Fuel Cell Stack The present invention is a fuel cell stack including at least one direct methanol fuel cell. A cathode manifold is used to convey ambient air to each fuel cell, and an anode manifold is used to convey liquid methanol fuel to each fuel cell. Tie-bolt penetrations and tie-bolts are spaced evenly around the perimeter to hold the fuel cell stack together. Each fuel cell uses two graphite-based plates. One plate includes a cathode active area that is defined by serpentine channels connecting the inlet manifold

243

Booster Synchrotron RF System Upgrade for SPEAR3  

Science Conference Proceedings (OSTI)

Recent progress at the SPEAR3 includes the increase in stored current from 100 mA to 200 mA and top-off injection to allow beamlines to stay open during injection. Presently the booster injects 3.0 GeV beam to SPEAR3 three times a day. The stored beam decays to about 150 mA between the injections. The growing user demands are to increase the stored current to the design value of 500 mA, and to maintain it at a constant value within a percent or so. To achieve this goal the booster must inject once every few minutes. For improved injection efficiency, all RF systems at the linac, booster and SPEAR3 need to be phase-locked. The present booster RF system is basically a copy of the SPEAR2 RF system with 358.5 MHz and 40 kW peak RF power driving a 5-cell RF cavity for 1.0 MV gap voltage. These requirements entail a booster RF system upgrade to a scaled down version of the SPEAR3 RF system of 476.3 MHz with 1.2 MW cw klystron output power capabilities. We will analyze each subsystem option for their merits within budgetary and geometric space constraints. A substantial portion of the system will come from the decommissioned PEP-II RF stations.

Park, Sanghyun; /SLAC; Corbett, Jeff; /SLAC

2012-07-06T23:59:59.000Z

244

High Power Co-Axial SRF Coupler  

SciTech Connect

There are over 35 coupler designs for SRF cavities ranging in frequency from 325 to 1500 MHz. Two-thirds of these designs are coaxial couplers using disk or cylindrical ceramics in various combinations and configurations. While it is well known that dielectric losses go down by several orders of magnitude at cryogenic temperatures, it not well known that the thermal conductivity also goes down, and it is the ratio of thermal conductivity to loss tangent (SRF ceramic Quality Factor) and ceramic volume which will determine the heat load of any given design. We describe a novel robust co-axial SRF coupler design which uses compressed window technology. This technology will allow the use of highly thermally conductive materials for cryogenic windows. The mechanical designs will fit into standard-sized ConFlat® flanges for ease of assembly. Two windows will be used in a coaxial line. The distance between the windows is adjusted to cancel their reflections so that the same window can be used in many different applications at various frequencies.

M.L. Neubauer, R.A. Rimmer

2009-05-01T23:59:59.000Z

245

Using a Balun Transformer Combiner for High Power Microwave Experiments  

Science Conference Proceedings (OSTI)

A novel coaxial power combiner design has been duplicated that has distinct advantages over other combiner geometries that can handle high power. This design is being applied to combine four 3 kW power supplies to obtain a 10 kW, 5 MHz system for an ICRF antenna on HSX. In the past, Wilkinson type combiners have had limited application to high power systems because of the lack of non-inductive, high power, 100 Omega balance loads. With this new design, standard 50 Omega dummy loads can be used instead for the balance load. The cost is considerably lower than lumped element combiner designs which are dominated by capacitor costs. At such a relatively low frequency, a 3-dB quarter-wave coupled-line coupler becomes impractically long, and a conventional branch-line hybrid requires 35 Omega-line, which is commercially unavailable. The balun combiner uses less transmission line than a ring hybrid and has good bandwidth characteristics even away from its best line impedance. Theoretical calculations and modeling were performed for line impedances from 65 Omega to 75 Omega. Measurements from a low-power test device show excellent agreement with theory, and construction of the high power system is underway.

Kaufman, Michael C [ORNL; Pesavento, Philip V [ORNL

2011-01-01T23:59:59.000Z

246

Pulsed power drivers for ICF and high energy density physics  

SciTech Connect

Nanosecond Pulsed Power Science and Technology has its origins in the 1960s and over the past decade has matured into a flexible and robust discipline capable of addressing key physics issues of importance to ICF and high Energy Density Physics. The major leverage provided by pulsed power is its ability to generate and deliver high energy and high power at low cost and high efficiency. A low-cost, high-efficiency driver is important because of the very large capital investment required for multi-megajoule ignition-class systems. High efficiency is of additional importance for a commercially viable inertial fusion energy option. Nanosecond pulsed power has been aggressively and successfully developed at Sandia over the past twenty years. This effort has led to the development of unique multi-purpose facilities supported by highly capable diagnostic, calculational and analytic capabilities. The Sandia Particle-beam Fusion Program has evolved as part of an integrated national ICF Program. It applies the low-cost, high-efficiency leverage provided by nanosecond pulsed power systems to the longer-term goals of the national program, i.e., the Laboratory Microfusion Facility and Inertial Fusion Energy. A separate effort has led to the application of nanosecond pulsed power to the generation of intense, high-energy laboratory x-ray sources for application to x-ray laser and radiation effects science research. Saturn is the most powerful of these sources to date. It generates {approximately}500 kilojoules of x-rays from a magnetically driven implosion (Z-pinch). This paper describes results of x-ray physics experiments performed on Saturn, plans for a new Z-pinch drive capability for PBFA-II, and a design concept for the proposed {approximately}15 MJ Jupiter facility. The opportunities for ICF-relevant research using these facilities will also be discussed.

Ramirez, J.J.; Matzen, M.K.; McDaniel, D.H.

1995-12-31T23:59:59.000Z

247

Rf heating of mirrors  

SciTech Connect

A brief overview is presented of potential uses for rf heating of plasmas in mirror devices. While some discussion relating to past experiments is given, the main emphasis is devoted to a review of potential experiments in presently existing devices, and devices under construction or planning. Some predictions are made for plasmas in mirror reactors.

Porkolab, M.

1980-04-09T23:59:59.000Z

248

Study of high quality indium nitride films grown on Si(100) substrate by RF-MOMBE with GZO and AlN buffer layers  

Science Conference Proceedings (OSTI)

Wurtzite structure InN films were prepared on Si(100) substrates using radio-frequency metal-organic molecular beam epitaxy (RF-MOMBE) system. Ga-doped ZnO (GZO) and Amorphous AlN (a-AlN) film were used as buffer layers for InN films growth. Structural, ...

Wei-Chun Chen, Shou-Yi Kuo

2012-01-01T23:59:59.000Z

249

Eccentric superconducting RF cavity separator structure  

DOE Patents (OSTI)

Accelerator apparatus having an eccentric-shaped, iris-loaded deflecting cavity for an rf separator for a high energy high momentum, charged particle accelerator beam. In one embodiment, the deflector is superconducting, and the apparatus of this invention provides simplified machining and electron beam welding techniques. Model tests have shown that the electrical characteristics provide the desired mode splitting without adverse effects.

Aggus, John R. (Shoreham, NY); Giordano, Salvatore T. (Port Jefferson, NY); Halama, Henry J. (Shoreham, NY)

1976-01-01T23:59:59.000Z

250

Towards Quantitative Simulations of High Power Proton Cyclotrons  

E-Print Network (OSTI)

PSI operates a cyclotron based high intensity proton accelerator routinely at an average beam power of 1.3MW. With this power the facility is at the worldwide forefront of high intensity proton accelerators. The beam current is practically limited by losses at extraction and the resulting activation of accelerator components. Further intensity upgrades and new projects aiming at an even higher average beam power, are only possible if the relative losses can be lowered in proportion, thus keeping absolute losses at a constant level. Maintaining beam losses at levels allowing hands-on maintenance is a primary challenge in any high power proton machine design and operation. In consequence, predicting beam halo at these levels is a great challenge and will be addressed in this paper. High power hadron driver have being used in many disciplines of science and, a growing interest in the cyclotron technology for high power hadron drivers are being observed very recently. This report will briefly introduce OPAL, a tool for precise beam dynamics simulations including 3D space charge. One of OPAL's flavors (OPAL-cycl) is dedicated to high power cyclotron modeling and is explained in greater detail. We then explain how to obtain initial conditions for our PSI Ring cyclotron which still delivers the world record in beam power of 1.3 MW continuous wave (cw). Several crucial steps are explained necessary to be able to predict tails at the level of 3\\sigma ... 4\\sigma in the PSI Ring cyclotron. We compare our results at the extraction with measurements, obtained with a 1.18 MW cw production beam. Based on measurement data, we develop a simple linear model to predict beam sizes of the extracted beam as a function of intensities and confirm the model with simulations.

Y. J. Bi; A. Adelmann; R. Dölling; M. Humbel; W. Joho; M. Seidel; T. J. Zhang

2010-12-03T23:59:59.000Z

251

IEEE ELECTRON DEVICE LETTERS, VOL. 28, NO. 5, MAY 2007 357 Direct Monitoring of RF Overstress in High-Power  

E-Print Network (OSTI)

to a nonuniform distribution of resultant voltage VRF across a loop, which is strongly affected by internal reflections in the device. In some cases, nonuniformity in VRF occurs due to parasitic oscillations

Shapira, Yoram

252

RF Design of the LCLS Gun  

Science Conference Proceedings (OSTI)

Final dimensions for the LCLS RF gun are described. This gun, referred to as the LCLS gun, is a modified version of the UCLA/BNL/SLAC 1.6 cell S-Band RF gun [1], referred to as the prototype gun. The changes include a larger mode separation (15 MHz for the LCLS gun vs. 3.5 MHz for the prototype gun), a larger radius at the iris between the 2 cells, a reduced surface field on the curvature of the iris between the two cells, Z power coupling, increased cooling channels for operation at 120 Hz, dual rf feed, deformation tuning of the full cell, and field probes in both cells. Temporal shaping of the klystron pulse, to reduce the average power dissipated in the gun, has also been adopted. By increasing the mode separation, the amplitude of the 0-mode electric field on the cathode decreases from 10% of the peak on axis field for the prototype gun to less than 3% for the LCLS gun for the steady state fields. Beam performance is improved as shown by the PARMELA simulations. The gun should be designed to accept a future load lock system. Modifications follow the recommendations of our RF review committee [2]. Files and reference documents are compiled in Section IV.

Limborg-Deprey, C

2010-12-13T23:59:59.000Z

253

E-beam high voltage switching power supply  

DOE Patents (OSTI)

A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360.degree./n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1997-01-01T23:59:59.000Z

254

E-beam high voltage switching power supply  

DOE Patents (OSTI)

A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360{degree}/n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load. 7 figs.

Shimer, D.W.; Lange, A.C.

1997-03-11T23:59:59.000Z

255

Advanced, High Power, Next Scale, Wave Energy Conversion Device  

SciTech Connect

The project conducted under DOE contract DE?EE0002649 is defined as the Advanced, High Power, Next Scale, Wave Energy Converter. The overall project is split into a seven?stage, gated development program. The work conducted under the DOE contract is OPT Stage Gate III work and a portion of Stage Gate IV work of the seven stage product development process. The project effort includes Full Concept Design & Prototype Assembly Testing building on our existing PowerBuoy? technology to deliver a device with much increased power delivery. Scaling?up from 150kW to 500kW power generating capacity required changes in the PowerBuoy design that addressed cost reduction and mass manufacturing by implementing a Design for Manufacturing (DFM) approach. The design changes also focused on reducing PowerBuoy Installation, Operation and Maintenance (IO&M) costs which are essential to reducing the overall cost of energy. In this design, changes to the core PowerBuoy technology were implemented to increase capability and reduce both CAPEX and OPEX costs. OPT conceptually envisaged moving from a floating structure to a seabed structure. The design change from a floating structure to seabed structure would provide the implementation of stroke? unlimited Power Take?Off (PTO) which has a potential to provide significant power delivery improvement and transform the wave energy industry if proven feasible.

Mekhiche, Mike [Principal Investigator] [Principal Investigator; Dufera, Hiz [Project Manager] [Project Manager; Montagna, Deb [Business Point of Contact] [Business Point of Contact

2012-10-29T23:59:59.000Z

256

Low cost high power GaSB photovoltaic cells  

Science Conference Proceedings (OSTI)

High power density and high capacity factor are important attributes of a thermophotovoltaics (TPV) system and GaSb cells are enabling for TPV systems. A TPV cogeneration unit at an off grid site will compliment solar arrays producing heat and electricity on cloudy days with the solar arrays generating electricity on sunny days. Herein

Lewis M. Fraas; Han X. Huang; Shi-Zhong Ye; She Hui; James Avery; Russell Ballantyne

1997-01-01T23:59:59.000Z

257

Low cost high power GaSb thermophotovoltaic cells  

Science Conference Proceedings (OSTI)

High power density and high capacity factor are important attributes of a TPV system and GaSb cells are enabling for TPV systems. A TPV cogeneration unit at an off grid site will compliment solar arrays producing heat and electricity on cloudy days with the solar arrays generating electricity on sunny days. Herein

Lewis M. Fraas; Han X. Huang; Shi-Zhong Ye; James Avery; Russell Ballantyne

1997-01-01T23:59:59.000Z

258

High-Level Power Minimization of Analog Sensor Interface Architectures  

Science Conference Proceedings (OSTI)

A high-level analog design and optimization tool was developed for the architectural synthesis of complex analog systems towards minimal power consumption. In this paper we will illustrate the use of this tool with the high-level design of an analog ...

Stéphane Donnay; Georges Gielen; Willy Sansen

1998-12-01T23:59:59.000Z

259

High Power Electrodynamics (HPE): Accelerator Operations and Technology,  

NLE Websites -- All DOE Office Websites (Extended Search)

CONTACTS CONTACTS Group Leader Bruce Carlsten Deputy Group Leader Ellen Guenette Administrator Josephine (Jo) Torres High-Power Electrodynamics (HPE) The High-Power Electrodynamics (AOT-HPE) Group applies accelerator and beam technologies to national-security-directed energy missions. AOT-HPE has three programmatic thrusts: free-electron lasers (FELs), high-power microwaves (HPM), and compact radiography. To maintain a vigorous and robust technical base for addressing DOE and DoD needs, the group's project portfolio is balanced between exploratory research, infrastructure development, and programmatic deliverables for sponsors. Funding is roughly 25% from the Lab's Directed Research and Development Program, 65% from DoD, and 10% from DOE. Technology Focus Areas AOT-HPE is the Laboratory's main vehicle for applying accelerator-based technologies to directed-energy mission needs. The group recognizes that many directed-energy missions are enabled by compact high-brightness electron accelerators and mm-wave and THz technologies.

260

HIGH EFFICIENCY FOSSIL POWER PLANT (HEFPP) CONCEPTUALIZATION PROGRAM  

SciTech Connect

This study confirms the feasibility of a natural gas fueled, 20 MW M-C Power integrated pressurized molten carbonate fuel cell combined in a topping cycle with a gas turbine generator plant. The high efficiency fossil power plant (HEFPP) concept has a 70% efficiency on a LHV basis. The study confirms the HEFPP has a cost advantage on a cost of electricity basis over the gas turbine based combined cycle plants in the 20 MW size range. The study also identifies the areas of further development required for the fuel cell, gas turbine generator, cathode blower, inverter, and power module vessel. The HEFPP concept offers an environmentally friendly power plant with minuscule emission levels when compared with the combined cycle power plant.

J.L. Justice

1999-03-25T23:59:59.000Z

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261

High Power Superconducting Continuous Wave Linacs for Protons and  

Office of Science (SC) Website

Power Superconducting Continuous Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives High Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: High Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions

262

High Power Microwave Switch Employing Electron Beam Triggering  

Science Conference Proceedings (OSTI)

A new type of switch for modulation of the Q-factor of a multi-mode storage resonator in a high-power active microwave pulse compressor is described. The operating principle of the switch is based on a sharp increase in the TE{sub 02{yields}}TE{sub 01} coupling coefficient, when an electron beam is injected into the switch cavity. The switch was tested at low power level in a compressor operated at X-band. A power gain of 19-20 in the compressed pulse with pulse duration of 40-50 ns was achieved. The proposed switch shows good prospects for use in high-power active pulse compressors.

Ivanov, O. A.; Vikharev, A. L. [Institute of Applied Physics RAS, Nizhny Novgorod, 603600 (Russian Federation); Omega-P, Inc., New Haven, Connecticut 06510 (United States); Isaev, V. A.; Lobaev, M. A. [Institute of Applied Physics RAS, Nizhny Novgorod, 603600 (Russian Federation); Hirshfield, J. L. [Omega-P, Inc., New Haven, Connecticut 06510 (United States); Department of Physics, Yale University, New Haven, Connecticut 06511 (United States)

2010-11-04T23:59:59.000Z

263

High efficiency carbonate fuel cell/turbine hybrid power cycle  

Science Conference Proceedings (OSTI)

The hybrid power cycle studies were conducted to identify a high efficiency, economically competitive system. A hybrid power cycle which generates power at an LHV efficiency > 70% was identified that includes an atmospheric pressure direct carbonate fuel cell, a gas turbine, and a steam cycle. In this cycle, natural gas fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming fuel. The mixed gas then flows to a direct carbonate fuel cell which generates about 70% of the power. The portion of the anode exhaust which is not recycled is burned and heat transferred through a heat exchanger (HX) to the compressed air from a gas turbine. The heated compressed air is then heated further in the gas turbine burner and expands through the turbine generating 15% of the power. Half the exhaust from the turbine provides air for the anode exhaust burner. All of the turbine exhaust eventually flows through the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Exhaust from the cathodes flows to a steam system (heat recovery steam generator, staged steam turbine generating 15% of the cycle power). Simulation of a 200 MW plant with a hybrid power cycle had an LHV efficiency of 72.6%. Power output and efficiency are insensitive to ambient temperature, compared to a gas turbine combined cycle; NOx emissions are 75% lower. Estimated cost of electricity for 200 MW is 46 mills/kWh, which is competitive with combined cycle where fuel cost is > $5.8/MMBTU. Key requirement is HX; in the 200 MW plant studies, a HX operating at 1094 C using high temperature HX technology currently under development by METC for coal gassifiers was assumed. A study of a near term (20 MW) high efficiency direct carbonate fuel cell/turbine hybrid power cycle has also been completed.

Steinfeld, G.; Maru, H.C. [Energy Research Corp., Danbury, CT (United States); Sanderson, R.A. [Sanderson (Robert) and Associates, Wethersfield, CT (United States)

1996-07-01T23:59:59.000Z

264

VUV absorption spectroscopy measurements of the role of fast neutral atoms in high-power gap breakdown  

DOE Green Energy (OSTI)

The maximum power achieved in a wide variety of high-power devices, including electron and ion diodes, z pinches, and microwave generators, is presently limited by anode-cathode gap breakdown. A frequently-discussed hypothesis for this effect is ionization of fast neutral atoms injected throughout the anode-cathode gap during the power pulse. The authors describe a newly-developed diagnostic tool that provides the first direct test of this hypothesis. Time-resolved vacuum-ultraviolet absorption spectroscopy is used to directly probe fast neutral atoms with 1 mm spatial resolution in the 10 mm anode-cathode gap of the SABRE 5 MV, 1 TW applied-B ion diode. Absorption spectra collected during Ar RF glow discharges and with CO{sub 2} gas fills confirm the reliability of the diagnostic technique. Throughout the 50--100 ns ion diode pulses no measurable neutral absorption is seen, setting upper limits of 0.12--1.5 x 10{sup 14} cm{sup {minus}3} for ground state fast neutral atom densities of H, C, N, O, F. The absence of molecular absorption bands also sets upper limits of 0.16--1.2 x 10{sup 15} cm{sup {minus}3} for common simple molecules. These limits are low enough to rule out ionization throughout the gap as a breakdown mechanism. This technique can now be applied to quantify the role of neutral atoms in other high-power devices.

FILUK,A.B.; BAILEY,JAMES E.; CUNEO,MICHAEL E.; LAKE,PATRICK WAYNE; NASH,THOMAS J.; NOACK,DONALD D.; MARON,Y.

2000-03-20T23:59:59.000Z

265

High-Power Microwave Switch Employing Electron Beam Triggering  

Science Conference Proceedings (OSTI)

A high-power active microwave pulse compressor is described that modulates the quality factor Q of the energy storage cavity by a new means involving mode conversion controlled by a triggered electron-beam discharge through a switch cavity. The electron beam is emitted from a diamond-coated molybdenum cathode. This report describes the principle of operation, the design of the switch, the configuration used for the test, and the experimental results. The pulse compressor produced output pulses with 140 - Ã?Â?165 MW peak power, power gain of 16 - 20, and pulse duration of 16 - 20 ns at a frequency of 11.43 GHz.

Jay L. Hirshfield

2012-09-19T23:59:59.000Z

266

A high-power switch-mode dc power supply for dynamic loads  

SciTech Connect

High-voltage dc power supplies are often required to operate with highly dynamic loads, such as arcs. A switch-mode dc power supply can offer significant advantages over conventional thyristor-based dc power supplies under such conditions. It can quickly turn off the supply to extinguish the arc, and it can quickly recover after the arc. It has a relatively small output filter capacitance, which results in small stored energy available to the arc. A 400-kW, 50-kV switch-mode dc power supply for an electron-beam gun that exploits these advantages was designed and tested. It uses four 100-kW, current-source-type dc-dc converters with inputs in parallel and outputs in series. The dc-dc converters operate at 20 kHz in the voltage regulator part and 10 kHz in the inverter, transformer, and output rectifier part of the circuit. Insulated gate bipolar transistors (IGBTs) are used as the power switches. Special techniques are used to protect the power supply and load against arcs and hard shorts. The power supply has an efficiency of 93%, an output voltage ripple of 1%, and fast dynamic response. In addition, it is nearly one-third the size of conventional power supplies.

Shimer, D.W.; Lange, A.C. [Lawrence Livermore National Lab., CA (United States); Bombay, J.N. [Kaiser Engineers, Oakland, CA (United States)

1994-06-23T23:59:59.000Z

267

Eccentric rf deflecting structure  

SciTech Connect

For superconducting rf separators, assembled by electron beam welding techniques, two types of mode stabilizers are discussed: the elliptical structure, and a new design called the eccentric structure''. For an operating pi /2 or pi mode in the lower pass band, it is shown that the various parameters of the eccentric structure can be adjusted to provide the required frequency spacing between the operating mode and the upper dispersion curve. (auth)

Aggus, J.R.; Giordano, S.; Halama, H.J.

1973-12-13T23:59:59.000Z

268

BN/Graphene/BN Transistors for RF Applications  

E-Print Network (OSTI)

In this letter, we demonstrate the first BN/graphene/BN field-effect transistor for RF applications. This device structure can preserve the high mobility and the high carrier velocity of graphene, even when it is sandwiched ...

Taychatanapat, Thiti

269

Advanced Power Supply Demonstration: High Frequency Power Supplies for Electrostatic Precipitator (ESP) Applications  

Science Conference Proceedings (OSTI)

New, high frequency supplies to power electrostatic precipitators (ESPs) are being introduced to the utility industry. These power supplies are smaller, lighter, and more versatile than the 60-Hz supplies they replace. As with so many new technologies, a number of problems have been encountered in some of the early applications. This report describes the principles of operation, the advantages and disadvantages, and the state of development of the new technology.

2004-03-23T23:59:59.000Z

270

Rf system for the NSLS coherent infrared radiation source  

Science Conference Proceedings (OSTI)

The existing NSLS X-ray Lithography Source (XLS Phase I) is being considered for a coherent synchrotron radiation source. The existing 211 MHz warm cavity will be replaced with a 5-cell 2856 MHz superconducting RF cavity, driven by a series of 2 kW klystrons. The RF system will provide a total V{sub RF} of 1.5 MV to produce {sigma}{sub L} = 0.3 mm electron bunches at an energy of 150 MeV. Superconducting technology significantly reduces the required space and power needed to achieve the higher voltage. It is the purpose of this paper to describe the superconducting RF system and cavity, power requirements, and cavity design parameters such as input coupling, Quality Factor, and Higher Order Modes.

Broome, W.; Biscardi, R.; Keane, J.; Mortazavi, P.; Thomas, M.; Wang, J.M.

1995-05-01T23:59:59.000Z

271

ANALYZING SURFACE ROUGHNESS DEPENDENCE OF LINEAR RF LOSSES  

SciTech Connect

Topographic structure on Superconductivity Radio Frequency (SRF) surfaces can contribute additional cavity RF losses describable in terms of surface RF reflectivity and absorption indices of wave scattering theory. At isotropic homogeneous extent, Power Spectrum Density (PSD) of roughness is introduced and quantifies the random surface topographic structure. PSD obtained from different surface treatments of niobium, such Buffered Chemical Polishing (BCP), Electropolishing (EP), Nano-Mechanical Polishing (NMP) and Barrel Centrifugal Polishing (CBP) are compared. A perturbation model is utilized to calculate the additional rough surface RF losses based on PSD statistical analysis. This model will not consider that superconductor becomes normal conducting at fields higher than transition field. One can calculate the RF power dissipation ratio between rough surface and ideal smooth surface within this field range from linear loss mechanisms.

Reece, Charles E. [JLAB; Kelley, Michael J. [JLAB, W& M College; Xu, Chen [JLAB, W& M College

2012-09-01T23:59:59.000Z

272

Programmatic status of NASA`s CSTI high capacity power Stirling Space Power Converter Program  

DOE Green Energy (OSTI)

An overview is presented of the NASA Lewis Research Center Free-Piston Stirling Space Power Converter Technology Development Program. This work is being conducted under NASA`s Civil Space Technology Initiative (CSTI). The goal of the CSTI High Capacity Power element is to develop the technology base needed to meet the long duration, high capacity power requirements for future NASA space initiatives. Efforts are focused upon increasing system thermal and electric energy conversion efficiency at least fivefold over current SP-100 technology, and on achieving systems that are compatible with space nuclear reactors. This paper will discuss the status of test activities with the Space Power Research Engine (SPRE). Design deficiencies are gradually being corrected and the power converter is now outputting 11.5 kWe at a temperature ratio of 2 (design output is 12.5 kWe). Detail designs have been completed for the 1050 K Component Test Power Converter (CTPC). The success of these and future designs is dependent upon supporting research and technology efforts including heat pipes, gas bearings, superalloy joining technologies and high efficiency alternators. This paper also provides an update of progress in these technologies.

Dudenhoefer, J.E.

1994-09-01T23:59:59.000Z

273

Fuel Cell/Turbine Ultra High Efficiency Power System  

DOE Green Energy (OSTI)

FuelCell Energy, INC. (FCE) is currently involved in the design of ultra high efficiency power plants under a cooperative agreement (DE-FC26-00NT40) managed by the National Energy Technology Laboratory (NETL) as part of the DOE's Vision 21 program. Under this project, FCE is developing a fuel cell/turbine hybrid system that integrates the atmospheric pressure Direct FuelCell{reg_sign} (DFC{reg_sign}) with an unfired Brayton cycle utilizing indirect heat recovery from the power plant. Features of the DFC/T{trademark} system include: high efficiency, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, no pressurization of the fuel cell, independent operating pressure of the fuel cell and turbine, and potential cost competitiveness with existing combined cycle power plants at much smaller sizes. Objectives of the Vision 21 Program include developing power plants that will generate electricity with net efficiencies approaching 75 percent (with natural gas), while producing sulfur and nitrogen oxide emissions of less than 0.01 lb/million BTU. These goals are significant improvements over conventional power plants, which are 35-60 percent efficient and produce emissions of 0.07 to 0.3 lb/million BTU of sulfur and nitrogen oxides. The nitrogen oxide and sulfur emissions from the DFC/T system are anticipated to be better than the Vision 21 goals due to the non-combustion features of the DFC/T power plant. The expected high efficiency of the DFC/T will also result in a 40-50 percent reduction in carbon dioxide emissions compared to conventional power plants. To date, the R&D efforts have resulted in significant progress including proof-of-concept tests of a sub-scale power plant built around a state-of-the-art DFC stack integrated with a modified Capstone Model 330 Microturbine. The objectives of this effort are to investigate the integration aspects of the fuel cell and turbine and to obtain design information and operational data that will be utilized in the design of a 40-MW high efficiency Vision 21 power plant. Additionally, these tests are providing the valuable insight for DFC/Turbine power plant potential for load following, increased reliability, and enhanced operability.

Hossein, Ghezel-Ayagh

2001-11-06T23:59:59.000Z

274

High Power SiC Modules for HEVs and PHEVs  

DOE Green Energy (OSTI)

With efforts to reduce the cost, size, and thermal management systems for the power electronics drivetrain in hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs), wide band gap semiconductors including silicon carbide (SiC) have been identified as possibly being a partial solution. Research on SiC power electronics has shown their higher efficiency compared to Si power electronics due to significantly lower conduction and switching losses. This paper focuses on the development of a high power module based on SiC JFETs and Schottky diodes. Characterization of a single device, a module developed using the same device, and finally an inverter built using the modules is presented. When tested at moderate load levels compared to the inverter rating, an efficiency of 98.2% was achieved by the initial prototype.

Chinthavali, Madhu Sudhan [ORNL; Tolbert, Leon M [ORNL; Zhang, Hui [ORNL; Han, Jung H [ORNL; Barlow, Fred D. [University of Idaho; Ozpineci, Burak [ORNL

2010-01-01T23:59:59.000Z

275

Spacecraft Power Beaming Using High-Energy Lasers, Experimental Validation  

SciTech Connect

The lifetime of many spacecrafts are often limited by degradation of their electrical power subsystem, e.g. radiation-damaged solar arrays or failed batteries. Being able to beam power from terrestrial sites using high energy lasers, could alleviate this limitation, extending the lifetime of billions of dollars of satellite assets, as well as providing additional energy for electric propulsion that can be used for stationkeeping and orbital changes. In addition, extensive research at the Naval Postgraduate School (NPS) has shown the potential for annealing damaged solar cells using lasers. This paper describes that research and a proposed experiment to demonstrate the relevant concepts of high energy laser power beaming to an NPS-built and operated satellite. Preliminary results of ground experiment of laser illuminations of some of the solar panels of one of the spacecrafts are also presented.

Michael, Sherif [Naval Postgraduate School ECE Dep./Space Systems Academic Group, Monterey, CA 93943 (United States)

2008-04-28T23:59:59.000Z

276

Living and Working Safely Around High-Voltage Power Lines.  

Science Conference Proceedings (OSTI)

High-voltage transmission lines can be just as safe as the electrical wiring in the homes--or just as dangerous. The crucial factor is ourselves: they must learn to behave safely around them. This booklet is a basic safety guide for those who live and work around power lines. It deals primarily with nuisance shocks due to induced voltages, and with potential electric shock hazards from contact with high-voltage lines. References on possible long-term biological effects of transmission lines are shown. In preparing this booklet, the Bonneville Power Administration has drawn on more than 50 years of experience with high-voltage transmission. BPA operates one of the world`s largest networks of long-distance, high-voltage lines. This system has more than 400 substations and about 15,000 miles of transmission lines, almost 4,400 miles of which are operated at 500,000 volts.

United States. Bonneville Power Administration.

2001-06-01T23:59:59.000Z

277

Transmutation and energy-production with high power accelerators  

SciTech Connect

Accelerator-driven transmutation offers attractive new solutions to complex nuclear problems. This paper outlines the basics of the technology, summarizes the key application areas, and discusses designs of and performance issues for the high-power proton accelerators that are required.

Lawrence, G.P.

1995-07-01T23:59:59.000Z

278

Thin liquid lithium targets for high power density  

E-Print Network (OSTI)

Thin liquid lithium targets for high power density applications: heavy ion beam strippers and beta Hilton Malmö City #12;Outline Liquid Lithium Stripper idea for FRIB Brief theory of film stability Thickness measurement results Next Steps Beta-beams 2 #12;Liquid Lithium Stripper for FRIB: Advantages

McDonald, Kirk

279

High Resolution PV Power Modeling for Distribution Circuit Analysis  

DOE Green Energy (OSTI)

NREL has contracted with Clean Power Research to provide 1-minute simulation datasets of PV systems located at three high penetration distribution feeders in the service territory of Southern California Edison (SCE): Porterville, Palmdale, and Fontana, California. The resulting PV simulations will be used to separately model the electrical circuits to determine the impacts of PV on circuit operations.

Norris, B. L.; Dise, J. H.

2013-09-01T23:59:59.000Z

280

First observations of power MOSFET burnout with high energy neutrons  

SciTech Connect

Single event burnout was seen in power MOSFETs exposed to high energy neutrons. Devices with rated voltage {ge}400 volts exhibited burnout at substantially less than the rated voltage. Tests with high energy protons gave similar results. Burnout was also seen in limited tests with lower energy protons and neutrons. Correlations with heavy-ion data are discussed. Accelerator proton data gave favorable comparisons with burnout rates measured on the APEX spacecraft. Implications for burnout at lower altitudes are also discussed.

Oberg, D.L.; Wert, J.L.; Normand, E.; Majewski, P.P. [Boeing Defense and Space Group, Seattle, WA (United States)] [Boeing Defense and Space Group, Seattle, WA (United States); Wender, S.A. [Los Alamos National Lab., NM (United States)] [Los Alamos National Lab., NM (United States)

1996-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

High power light emitting diode based setup for photobleaching fluorescent impurities  

E-Print Network (OSTI)

High power light emitting diode based setup for photobleaching fluorescent impurities Tobias K be photobleached before final sample preparation. The instrument consists of high power light emitting diodes

Kaufman, Laura

282

Design and 3D simulation of a two-cavity wide-gap relativistic klystron amplifier with high power injection  

Science Conference Proceedings (OSTI)

By using an electromagnetic particle-in-cell (PIC) code, an S-band two-cavity wide-gap klystron amplifier (WKA) loaded with washers/rods structure is designed and investigated for high power injection application. Influences of the washers/rods structure on the high frequency characteristics and the basic operation of the amplifier are presented. Generally, the rod structure has great impacts on the space-charge potential depression and the resonant frequency of the cavities. Nevertheless, if only the resonant frequency is tuned to the desired operation frequency, effects of the rod size on the basic operation of the amplifier are expected to be very weak. The 3-dimension (3-D) PIC simulation results show an output power of 0.98 GW corresponding to an efficiency of 33% for the WKA, with a 594 keV, 5 kA electron beam guided by an external magnetic field of 1.5 Tesla. Moreover, if a conductive plane is placed near the output gap, such as the electron collector, the beam potential energy can be further released, and the RF power can be increased to about 1.07 GW with the conversion efficiency of about 36%.

Bai Xianchen; Yang Jianhua; Zhang Jiande [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2012-08-15T23:59:59.000Z

283

Coal-fired high performance power generating system. Final report  

SciTech Connect

As a result of the investigations carried out during Phase 1 of the Engineering Development of Coal-Fired High-Performance Power Generation Systems (Combustion 2000), the UTRC-led Combustion 2000 Team is recommending the development of an advanced high performance power generation system (HIPPS) whose high efficiency and minimal pollutant emissions will enable the US to use its abundant coal resources to satisfy current and future demand for electric power. The high efficiency of the power plant, which is the key to minimizing the environmental impact of coal, can only be achieved using a modern gas turbine system. Minimization of emissions can be achieved by combustor design, and advanced air pollution control devices. The commercial plant design described herein is a combined cycle using either a frame-type gas turbine or an intercooled aeroderivative with clean air as the working fluid. The air is heated by a coal-fired high temperature advanced furnace (HITAF). The best performance from the cycle is achieved by using a modern aeroderivative gas turbine, such as the intercooled FT4000. A simplified schematic is shown. In the UTRC HIPPS, the conversion efficiency for the heavy frame gas turbine version will be 47.4% (HHV) compared to the approximately 35% that is achieved in conventional coal-fired plants. This cycle is based on a gas turbine operating at turbine inlet temperatures approaching 2,500 F. Using an aeroderivative type gas turbine, efficiencies of over 49% could be realized in advanced cycle configuration (Humid Air Turbine, or HAT). Performance of these power plants is given in a table.

1995-08-31T23:59:59.000Z

284

Analysis and design of high frequency link power conversion systems for fuel cell power conditioning  

E-Print Network (OSTI)

In this dissertation, new high frequency link power conversion systems for the fuel cell power conditioning are proposed to improve the performance and optimize the cost, size, and weight of the power conversion systems. The first study proposes a new soft switching technique for the phase-shift controlled bi-directional dc-dc converter. The described dc-dc converter employs a low profile high frequency transformer and two active full-bridge converters for bidirectional power flow capability. The proposed new soft switching technique guarantees soft switching over wide range from no load to full load without any additional circuit components. The load range for proposed soft switching technique is analyzed by mathematical approach with equivalent circuits and verified by experiments. The second study describes a boost converter cascaded high frequency link direct dc-ac converter suitable for fuel cell power sources. A new multi-loop control for a boost converter to reduce the low frequency input current harmonics drawn from the fuel cell is proposed, and a new PWM technique for the cycloconverter at the secondary to reject the low order harmonics in the output voltages is presented. The performance of the proposed scheme is verified by the various simulations and experiments, and their trade-offs are described in detail using mathematical evaluation approach. The third study proposes a current-fed high frequency link direct dc-ac converter suitable for residential fuel cell power systems. The high frequency full-bridge inverter at the primary generates sinusoidally PWM modulated current pulses with zero current switching (ZCS), and the cycloconverter at the secondary which consists of only two bidirectional switches and output filter capacitors produces sinusoidally modulated 60Hz split single phase output voltage waveforms with near zero current switching. The active harmonic filter connected to the input terminal compensates the low order input current harmonics drawn from the fuel cell without long-term energy storage devices such as batteries and super capacitors.

Song, Yu Jin

2004-08-01T23:59:59.000Z

285

RF current sensor  

DOE Patents (OSTI)

An RF sensor having a novel current sensing probe and a voltage sensing probe to measure voltage and current. The current sensor is disposed in a transmission line to link all of the flux generated by the flowing current in order to obtain an accurate measurement. The voltage sensor is a flat plate which operates as a capacitive plate to sense voltage on a center conductor of the transmission line, in which the measured voltage is obtained across a resistance leg of a R-C differentiator circuit formed by the characteristic impedance of a connecting transmission line and a capacitance of the plate, which is positioned proximal to the center conductor.

Moore, James A. (Powell, TN); Sparks, Dennis O. (Maryville, TN)

1998-11-10T23:59:59.000Z

286

Capacitive charging system for high power battery charging  

DOE Green Energy (OSTI)

This document describes a project to design, build, demonstrate, and document a Level 3 capacitive charging system, and it will be based on the existing PEZIC prototype capacitive coupler. The capacitive coupler will be designed to transfer power at a maximum of 600 kW, and it will transfer power by electric fields. The power electronics will transfer power at 100 kW. The coupler will be designed to function with future increases in the power electronics output power and increases in the amp/hours capacity of sealed batteries. Battery charging algorithms will be programmed into the control electronics. The finished product will be a programmable battery charging system capable of transferring 100 kW via a capacitive coupler. The coupler will have a low power loss of less than 25 watts when transferring 240 kW (400 amps). This system will increase the energy efficiency of high power battery charging, and it will enhance mobility by reducing coupler failures. The system will be completely documented. An important deliverable of this project is information. The information will be distributed to the Army`s TACOM-TARDEC`s Advanced Concept Group, and it will be distributed to commercial organizations by the Society of Automotive Engineers. The information will be valuable for product research, development, and specification. The capacitive charging system produced in this project will be of commercial value for future electric vehicles. The coupler will be designed to rapid charge batteries that have a capacity of several thousand amp/hours at hundreds of volts. The charging system built here will rapid charge batteries with several hundred amp/hours capacity, depending on the charging voltage.

NONE

1998-12-31T23:59:59.000Z

287

Implications of high efficiency power cycles for fusion reactor design  

SciTech Connect

The implications of the High Efficiency Power Cycle for fusion reactors are examined. The proposed cycle converts most all of the high grade CTR heat input to electricity. A low grade thermal input (T approximately 100$sup 0$C) is also required, and this can be supplied at low cost geothermal energy at many locations in the U. S. Approximately 3 KW of low grade heat is required per KW of electrical output. The thermodynamics and process features of the proposed cycle are discussed. Its advantages for CTR's are that low Q machines (e.g. driven Tokamaks, mirrors) can operate with a high (approximately 80 percent) conversion of CTR fusion energy to electricity, where with conventional power cycles no plant output could be achieved with such low Q operation. (auth)

Powell, J.R.; Usher, J.; Salzano, F.J.

1975-01-01T23:59:59.000Z

288

Conversion Tower for Dispatchable Solar Power: High-Efficiency Solar-Electric Conversion Power Tower  

Science Conference Proceedings (OSTI)

HEATS Project: Abengoa Solar is developing a high-efficiency solar-electric conversion tower to enable low-cost, fully dispatchable solar energy generation. Abengoa’s conversion tower utilizes new system architecture and a two-phase thermal energy storage media with an efficient supercritical carbon dioxide (CO2) power cycle. The company is using a high-temperature heat-transfer fluid with a phase change in between its hot and cold operating temperature. The fluid serves as a heat storage material and is cheaper and more efficient than conventional heat-storage materials, like molten salt. It also allows the use of a high heat flux solar receiver, advanced high thermal energy density storage, and more efficient power cycles.

None

2012-01-11T23:59:59.000Z

289

SLAC Next-Generation High Availability Power Supply  

SciTech Connect

SLAC recently commissioned forty high availability (HA) magnet power supplies for Japan's ATF2 project. SLAC is now developing a next-generation N+1 modular power supply with even better availability and versatility. The goal is to have unipolar and bipolar output capability. It has novel topology and components to achieve very low output voltage to drive superconducting magnets. A redundant, embedded, digital controller in each module provides increased bandwidth for use in beam-based alignment, and orbit correction systems. The controllers have independent inputs for connection to two external control nodes. Under fault conditions, they sense failures and isolate the modules. Power supply speed mitigates the effects of fault transients and obviates subsequent magnet standardization. Hot swap capability promises higher availability and other exciting benefits for future, more complex, accelerators, and eventually the International Linear Collider project.

Bellomo, P.; MacNair, D.; /SLAC; ,

2010-06-11T23:59:59.000Z

290

The effect of high penetration of wind power on primary frequency control of power systems.  

E-Print Network (OSTI)

??In this work, a power system with wind power units and hydro power units are considered. The hydro power unit and variable speed wind turbine… (more)

Motamed, Bardia

2013-01-01T23:59:59.000Z

291

Accelerator and rf system development for NLC  

Science Conference Proceedings (OSTI)

An experimental station for an X-band Next Linear Collider has been constructed at SLAC. This station consists of a klystron and modulator, a low-loss waveguide system for rf power distribution, a SLED II pulse-compression and peak-power multiplication system, acceleration sections and beam-line components (gun, prebuncher, preaccelerator, focussing elements and spectrometer). An extensive program of experiments to evaluate the performance of all components is underway. The station is described in detail in this paper, and results to date are presented.

Vlieks, A.E.; Callin, R.; Deruyter, H. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)] [and others

1993-04-01T23:59:59.000Z

292

High power battery test methods for hybrid vehicle applications  

DOE Green Energy (OSTI)

Commonly used EV battery tests are not very suitable for testing hybrid vehicle batteries, which may be primarily intended to supply vehicle acceleration power. The capacity of hybrid vehicle batteries will be relatively small, they will typically operate over a restricted range of states-of-charge, and they may seldom if ever be fully recharged. Further, hybrid propulsion system designs will commonly impose a higher regeneration content than is typical for electric vehicles. New test methods have been developed for use in characterizing battery performance and life for hybrid vehicle use. The procedures described in this paper were developed from the requirements of the government-industry cooperative Partnership for A New Generation of Vehicles (PNGV) program; however, they are expected to have broad application to the testing of energy storage devices for hybrid vehicles. The most important performance measure for a high power battery is its pulse power capability as a function of state-of-charge for both discharge and regeneration pulses. It is also important to characterize cycle life, although the {open_quote}cycles{close_quote} involved are quite different from the conventional full-discharge, full-recharge cycle commonly used for EV batteries, This paper illustrates in detail several test profiles which have been selected for PNGV battery testing, along with some sample results and lessons learned to date from the use of these test profiles. The relationship between the PNGV energy storage requirements and these tests is described so that application of the test methods can be made to other hybrid vehicle performance requirements as well. The resulting test procedures can be used to characterize the pulse power capability of high power energy storage devices including batteries and ultracapacitors, as well as the life expectancy of such devices, for either power assist or dual mode hybrid propulsion system designs.

Hunt, G.L.; Haskins, H.; Heinrich, B.; Sutula, R.

1997-11-01T23:59:59.000Z

293

Design of traveling wave windows for the PEP-II RF coupling network  

SciTech Connect

The waveguide windows in the PEP-II RF coupling network have to withstand high power of 500 kW. Traveling wave windows have lower power dissipation than conventional self-matched windows, thus rendering the possibility of less stringent mechanical design. The traveling wave behavior is achieved by providing a reflecting iris on each side of the window, and depending on the configuration of the irises, traveling wave windows are characterized as inductive or capacitive types. A numerical design procedure using MAFIA has been developed for traveling wave windows. The relative advantages of inductive and capacitive windows are discussed. Furthermore, the issues of bandwidth and multipactoring are also addressed.

Kroll, N.M.; Ng, C.K.; Judkins, J.; Neubauer, M.

1995-05-01T23:59:59.000Z

294

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Laser Seeding Yields High-Power Coherent Terahertz Radiation Print Laser Seeding Yields High-Power Coherent Terahertz Radiation Print Researchers at Berkeley Lab have been exploring the ways coherent synchrotron radiation (CSR) is generated in electron storage rings when femtosecond lasers are used to carve out ultrafast x-ray pulses by femtoslicing (see "Tailored Terahertz Pulses from a Laser-Modulated Electron Beam"). In their most recent work, the researchers reported the first observation of seeding an instability of the electron beam by the laser, and they presented a physical model that shows how this occurs under the proper conditions. Such a mechanism makes it possible to control the instability onset and to exploit its gain for the generation of pulses of terahertz CSR of unprecedented power. Terahertz radiation with a wavelength from about 1 cm to about 100 microns between the microwave and the infrared would provide access to a large number of fundamental phenomena. To mention only some of them: excited electrons orbit, small molecules rotate, proteins vibrate, superconducting energy gaps resonate, and gaseous and solid-state plasmas oscillate at terahertz frequencies. But generating terahertz radiation is ordinarily a challenging task for any kind of source, including storage-ring-based synchrotron light sources. The new findings by the ALS group could represent a significant step toward satisfying the need for powerful terahertz sources.

295

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Laser Seeding Yields High-Power Coherent Terahertz Radiation Print Laser Seeding Yields High-Power Coherent Terahertz Radiation Print Researchers at Berkeley Lab have been exploring the ways coherent synchrotron radiation (CSR) is generated in electron storage rings when femtosecond lasers are used to carve out ultrafast x-ray pulses by femtoslicing (see "Tailored Terahertz Pulses from a Laser-Modulated Electron Beam"). In their most recent work, the researchers reported the first observation of seeding an instability of the electron beam by the laser, and they presented a physical model that shows how this occurs under the proper conditions. Such a mechanism makes it possible to control the instability onset and to exploit its gain for the generation of pulses of terahertz CSR of unprecedented power. Terahertz radiation with a wavelength from about 1 cm to about 100 microns between the microwave and the infrared would provide access to a large number of fundamental phenomena. To mention only some of them: excited electrons orbit, small molecules rotate, proteins vibrate, superconducting energy gaps resonate, and gaseous and solid-state plasmas oscillate at terahertz frequencies. But generating terahertz radiation is ordinarily a challenging task for any kind of source, including storage-ring-based synchrotron light sources. The new findings by the ALS group could represent a significant step toward satisfying the need for powerful terahertz sources.

296

Understanding High-Power Fiber-Optic Laser Beam Delivery  

NLE Websites -- All DOE Office Websites (Extended Search)

High-Power Fiber-Optic Laser Beam Delivery High-Power Fiber-Optic Laser Beam Delivery The submitted manuscript has been authored by a contractor of the U.S. Government under contract No. W- 31-109-ENG-38. Accordingly, the U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U.S. Government purposes. Boyd V. Hunter and Keng H. Leong Argonne National Laboratory Technology Development Division Laser Applications Laboratory 9700 South Cass Avenue, Building 207 Argonne, Illinois 60439 Carl B. Miller, James F. Golden, Robert D. Glesias and Patrick J. Laverty U. S. Laser Corporation 825 Windham Court North P. O. Box 609 Wyckoff, New Jersey 07481 March 25, 1996 Manuscript to be submitted to Journal of Laser Applications

297

RF Breakdown of Metallic Surfaces in Hydrogen  

DOE Green Energy (OSTI)

In earlier reports, microscopic images of the surfaces of metallic electrodes used in high-pressure gas-filled 805 MHz RF cavity experiments were used to investigate the mechanism of RF breakdown of tungsten, molybdenum, and beryllium electrode surfaces. Plots of remnants were consistent with the breakdown events being due to field emission, due to the quantum mechanical tunnelling of electrons through a barrier as described by Fowler and Nordheim. In the work described here, these studies have been extended to include tin, aluminium, and copper. Contamination of the surfaces, discovered after the experiments concluded, have cast some doubt on the proper qualities to assign to the metallic surfaces. However, two significant results are noted. First, the maximum stable RF gradient of contaminated copper electrodes is higher than for a clean surface. Second, the addition of as little as 0.01% of SF6 to the hydrogen gas increased the maximum stable gradient, which implies that models of RF breakdown in hydrogen gas will be important to the study of metallic breakdown.

BastaniNejad, M.; Elmustafa, A.A.; /Old Dominion U.; Yonehara, K.; Chung, M.; Jansson, A.; Hu, M.; Moretti, A.; Popovic, M.; /Fermilab; Alsharo'a, M.; Neubauer, M.; Sah, R.; /Muons Inc., Batavia

2009-05-01T23:59:59.000Z

298

NSLS-II RF SYSTEMS  

Science Conference Proceedings (OSTI)

The NSLS-II is a new third generation light source being constructed at Brookhaven Lab. The storage ring is optimized for low emittance by use of damping wigglers to reduce the emittance to below 1 nm-rad. The RF systems are designed to provide stable beam through tight RF phase and amplitude stability requirements.

Rose, J.; Gash, W.; Holub, B.; Kawashima, Y.; Ma, H.; Towne, N.; Yeddulla, M.

2011-03-28T23:59:59.000Z

299

High average power magnetic modulator for metal vapor lasers  

DOE Patents (OSTI)

A three-stage magnetic modulator utilizing magnetic pulse compression designed to provide a 60 kV pulse to a copper vapor laser at a 4.5 kHz repetition rate is disclosed. This modulator operates at 34 kW input power. The circuit includes a step up auto transformer and utilizes a rod and plate stack construction technique to achieve a high packing factor.

Ball, Don G. (Livermore, CA); Birx, Daniel L. (Oakley, CA); Cook, Edward G. (Livermore, CA); Miller, John L. (Livermore, CA)

1994-01-01T23:59:59.000Z

300

High-power regenerative Nd-phosphate glass amplifier  

Science Conference Proceedings (OSTI)

A compact high-power regenerative Nd-phosphate glass amplifier is described which incorporates spatial filtering and full image relay techniques. Output energies up to 1.2 J at a pulse duration of 140 +- 10 psec (FWHM) and 3 J at 900 +- 70 psec (FWHM) are achieved in a smooth nearly flattop beam intensity profile. Even with present-day technology, this system could be scaled into a terawatt regime.

Roschger, E.W.; Balmer, J.E.

1985-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Prediction of Power Requirements for High-Speed Circuits  

E-Print Network (OSTI)

. Modern VLSI design methodologies and manufacturing technologies are making circuits increasingly fast. The quest for higher circuit performance and integration density stems from fields such as the telecommunication one where high speed and capability of dealing with large data sets is mandatory. The design of high-speed circuits is a challenging task, and can be carried out only if designers can exploit suitable CAD tools. Among the several aspects of high-speed circuit design, controlling power consumption is today a major issue for ensuring that circuits can operate at full speed without damages. In particular, tools for fast and accurate estimation of power consumption of highspeed circuits are required. In this paper we focus on the problem of predicting the maximum power consumption of sequential circuits. We formulate the problem as a constrained optimization problem, and solve it resorting to an evolutionary algorithm. Moreover, we empirically assess the effectiveness of our problem formulation with respect to the classical unconstrained formulation. Finally, we report experimental results assessing the effectiveness of the prototypical tool we implemented. 1.

Corno Rebaudengo Sonza; F. Corno; M. Rebaudengo; M. Sonza Reorda; G. Squillero; M. Violante

2000-01-01T23:59:59.000Z

302

Optimization Studies for ISOL Type High-Powered Targets  

Science Conference Proceedings (OSTI)

The research studied one-step and two-step Isotope Separation on Line (ISOL) targets for future radioactive beam facilities with high driver-beam power through advanced computer simulations. As a target material uranium carbide in the form of foils was used because of increasing demand for actinide targets in rare-isotope beam facilities and because such material was under development in ISAC at TRIUMF when this project started. Simulations of effusion were performed for one-step and two step targets and the effects of target dimensions and foil matrix were studied. Diffusion simulations were limited by availability of diffusion parameters for UCx material at reduced density; however, the viability of the combined diffusion?effusion simulation methodology was demonstrated and could be used to extract physical parameters such as diffusion coefficients and effusion delay times from experimental isotope release curves. Dissipation of the heat from the isotope-producing targets is the limiting factor for high-power beam operation both for the direct and two-step targets. Detailed target models were used to simulate proton beam interactions with the targets to obtain the fission rates and power deposition distributions, which were then applied in the heat transfer calculations to study the performance of the targets. Results indicate that a direct target, with specification matching ISAC TRIUMF target, could operate in 500-MeV proton beam at beam powers up to ~40 kW, producing ~8 1013 fission/s with maximum temperature in UCx below 2200 C. Targets with larger radius allow higher beam powers and fission rates. For the target radius in the range 9-mm to 30-mm the achievable fission rate increases almost linearly with target radius, however, the effusion delay time also increases linearly with target radius.

Remec, Igor [Oak Ridge National Laboratory] [Oak Ridge National Laboratory; Ronningen, Reginald Martin [Michigan State University] [Michigan State University

2013-09-24T23:59:59.000Z

303

High average power diode pumped solid state lasers for CALIOPE  

Science Conference Proceedings (OSTI)

Diode pumping of solid state media offers the opportunity for very low maintenance, high efficiency, and compact laser systems. For remote sensing, such lasers may be used to pump tunable non-linear sources, or if tunable themselves, act directly or through harmonic crystals as the probe. The needs of long range remote sensing missions require laser performance in the several watts to kilowatts range. At these power performance levels, more advanced thermal management technologies are required for the diode pumps. The solid state laser design must now address a variety of issues arising from the thermal loads, including fracture limits, induced lensing and aberrations, induced birefringence, and laser cavity optical component performance degradation with average power loading. In order to highlight the design trade-offs involved in addressing the above issues, a variety of existing average power laser systems are briefly described. Included are two systems based on Spectra Diode Laboratory`s water impingement cooled diode packages: a two times diffraction limited, 200 watt average power, 200 Hz multi-rod laser/amplifier by Fibertek, and TRW`s 100 watt, 100 Hz, phase conjugated amplifier. The authors also present two laser systems built at Lawrence Livermore National Laboratory (LLNL) based on their more aggressive diode bar cooling package, which uses microchannel cooler technology capable of 100% duty factor operation. They then present the design of LLNL`s first generation OPO pump laser for remote sensing. This system is specified to run at 100 Hz, 20 nsec pulses each with 300 mJ, less than two times diffraction limited, and with a stable single longitudinal mode. The performance of the first testbed version will be presented. The authors conclude with directions their group is pursuing to advance average power lasers. This includes average power electro-optics, low heat load lasing media, and heat capacity lasers.

Comaskey, B.; Halpin, J.; Moran, B.

1994-07-01T23:59:59.000Z

304

Thulium heat source for high-endurance and high-energy density power systems  

DOE Green Energy (OSTI)

We are studying the performance characteristics of radioisotope heat source designs for high-endurance and high-energy-density power systems that use thulium-170. Heat sources in the power range of 5--50 kW{sub th} coupled with a power conversion efficiency of {approximately}30%, can easily satisfy current missions for autonomous underwater vehicles. New naval missions will be possible because thulium isotope power systems have a factor of one-to-two hundred higher endurance and energy density than chemical and electrochemical systems. Thulium-170 also has several other attractive features, including the fact that it decays to stable ytterbium-170 with a half-life of four months. For terrestrial applications, refueling on that time scale should be acceptable in view of the advantage of its benign decay. The heat source designs we are studying account for the requirements of isotope production, shielding, and integration with power conversion components. These requirements are driven by environmental and safety considerations. Thulium is present in the form of thin refractory thulia disks that allow power conversion at high peak temperature. We give estimates of power system state points, performance, mass, and volume characteristics. Monte Carlo radiation analysis provides a detailed assessment of shield requirements and heat transfer under normal and distressed conditions is also considered. 11 refs., 7 figs., 4 tabs.

Walter, C.E.; Kammeraad, J.E.; Van Konynenburg, R.; VanSant, J.H.

1991-05-01T23:59:59.000Z

305

Technology survey and performance scaling for the design of high power nuclear electric power and propulsion systems  

E-Print Network (OSTI)

High power nuclear electric propulsion systems have the capability to enable many next-generation space exploration applications. To date, use of electric primary propulsion in flight systems has been limited to low-power, ...

White, Daniel B., Jr

2011-01-01T23:59:59.000Z

306

A High Efficiency PSOFC/ATS-Gas Turbine Power System  

DOE Green Energy (OSTI)

A study is described in which the conceptual design of a hybrid power system integrating a pressurized Siemens Westinghouse solid oxide fuel cell generator and the Mercury{trademark} 50 gas turbine was developed. The Mercury{trademark} 50 was designed by Solar Turbines as part of the US. Department of Energy Advanced Turbine Systems program. The focus of the study was to develop the hybrid power system concept that principally would exhibit an attractively-low cost of electricity (COE). The inherently-high efficiency of the hybrid cycle contributes directly to achieving this objective, and by employing the efficient, power-intensive Mercury{trademark} 50, with its relatively-low installed cost, the higher-cost SOFC generator can be optimally sized such that the minimum-COE objective is achieved. The system cycle is described, major system components are specified, the system installed cost and COE are estimated, and the physical arrangement of the major system components is discussed. Estimates of system power output, efficiency, and emissions at the system design point are also presented. In addition, two bottoming cycle options are described, and estimates of their effects on overall-system performance, cost, and COE are provided.

W.L. Lundberg; G.A. Israelson; M.D. Moeckel; S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann

2001-02-01T23:59:59.000Z

307

Discharge Physics of High Power Impulse Magnetron Sputtering  

SciTech Connect

High power impulse magnetron sputtering (HIPIMS) is pulsed sputtering where the peak power exceeds the time-averaged power by typically two orders of magnitude. The peak power density, averaged over the target area, can reach or exceed 107 W/m2, leading to plasma conditions that make ionization of the sputtered atoms very likely. A brief review of HIPIMS operation is given in a tutorial manner, illustrated by some original data related to the self-sputtering of niobium in argon and krypton. Emphasis is put on the current-voltage-time relationships near the threshold of self-sputtering runaway. The great variety of current pulse shapes delivers clues on the very strong gas rarefaction, self-sputtering runaway conditions, and the stopping of runaway due to the evolution of atom ionization and ion return probabilities as the gas plasma is replaced by metal plasma. The discussions are completed by considering instabilities and the special case of ?gasless? self-sputtering.

Anders, Andre

2010-10-13T23:59:59.000Z

308

MSTC - Microsystems Science, Technology, and Components - RF...  

NLE Websites -- All DOE Office Websites (Extended Search)

capability for the unique demands of National Security. Communications RF MEMS Passive wireless sensorsRFIDsTags RF system minaturization For additional information or...

309

Highly Conductive and Porous Activated Reduced Graphene Oxide Films for High-Power Supercapacitors  

E-Print Network (OSTI)

Highly Conductive and Porous Activated Reduced Graphene Oxide Films for High-Power Supercapacitors for a free-standing carbon film reported to date. A two-electrode supercapacitor using these carbon films. KEYWORDS: Graphene, flexible film, chemical activation, supercapacitors Free-standing thin film materials

310

Options for an 11 GeV RF Beam Separator for the Jefferson Lab CEBAF Upgrade  

Science Conference Proceedings (OSTI)

The CEBAF accelerator at Jefferson Lab has had, since first demonstration in 1996, the ability to deliver a 5-pass electron beam to experimental halls (A, B, and C) simultaneously. This capability was provided by a set of three, room temperature 499 MHz rf separators in the 5th pass beamline. The separator was two-rod, TEM mode type resonator, which has a high shunt impedance. The maximum rf power to deflect the 6 GeV beams was about 3.4kW. The 12 GeV baseline design does not preserve the capability of separating the 5th pass, 11 GeV beam for the 3 existing halls. Several options for restoring this capability, including extension of the present room temperature system or a new superconducting design in combination with magnetic systems, are under investigation and are presented.

Jean Delayen, Michael Spata, Haipeng Wang

2009-05-01T23:59:59.000Z

311

A high average power electro-optic switch using KTP  

SciTech Connect

High damage threshold, high thermal conductivity, and small thermo-optic coefficients make KTiOPO{sub 4} (KTP) an attractive material for use in a high average power Q-switch. However, electro-chromic damage and refractive index homogeneity have prevented the utilization of KTP in such a device in the past. This work shows that electro-chromic damage is effectively suppressed using capacitive coupling, and a KTP crystal can be Q-switched for 1.5 {times} 10{sup 9} shots without any detectable electro-chromic damage. In addition, KTP with the high uniformity and large aperture size needed for a KTP electro-optic Q-switch can be obtained from flux crystals grown at constant temperature. A thermally compensated, dual crystal KTP Q-switch, which successfully produced 50 mJ pulses with a pulse width of 8 ns (FWHM), has been constructed. In addition, in off-line testing the Q-switch showed less than 7% depolarization at an average power loading of 3.2 kW/cm{sup 2}.

Ebbers, C.A.; Cook, W.M.; Velsko, S.P.

1994-04-01T23:59:59.000Z

312

Optically powered firing system for the Procyon high explosive pulse power system  

DOE Green Energy (OSTI)

An optically powered fireset has been developed for the Procyon high explosive pulsed-power generator at Los Alamos National Laboratory. The fireset was located inside this flux compression experiment where large magnetic fields are generated. No energy sources were allowed inside the experiment and no wire connections can penetrate through the wall, of the experiment because of the high magnetic fields. The flux compression was achieved with high explosives in the experiment. The fireset was used to remotely charge a 1.2 {micro}f capacitor to 6,500V and to provide a readout of the voltage on the capacitor at the control room. The capacitor was charged by using two 7W fiber coupled GaAlAs laser diodes to illuminate two fiber coupled 12V solar cells. The solar cell outputs were connected in parallel to the input of a DC-DC converter which step up a 12V to 6,500V. A voltmeter, powered by illuminating a third 12V solar cell with 1W laser diode, was used to monitor the charge on the capacitor. The voltage was measured with a divider circuit, then converted to frequency in a V-F converter and transmitted to the control room over a fiber optic link. A fiducial circuit measured the capacitor firing current and provided an optical output timing pulse.

Earley, L.; Paul, J.; Rohlev, L.; Goforth, J.; Hall, C.R.

1995-10-01T23:59:59.000Z

313

Zero-switching-loss inverters for high-power applications  

SciTech Connect

The development of zero-switching-loss inverters has attracted much interest for industrial applications. The resonant dc link inverter (RDCLI) provides a simple and robust approach for realizing switching frequencies >20 kHz in multi-kilowatt systems but impresses substantial voltage stress (-- 2.5 supply voltage) across the devices. Two alternate topologies for realizing zero switching losses in high-power converters are proposed. The actively clamped resonant dc-link inverter (ACRLI) uses the concept of a lossless active clamp to restrict voltage stresses to only 1.3-1.5 supply voltage (V/sub s/) while maintaining a mode of operation similar to the RDCLI. For applications demanding substantially superior spectral performance, the resonant pole inverter (RPI), also called the quasi-resonant current mode inverter (QRCMI), is proposed as a viable topology. Detailed analysis, simulation, and experimental results are presented to verify operation principles of both power converters.

Divan, D.M.; Skibinski, G. (Wisconsin Univ., Madison, WI (USA). Dept. of Electrical and Computer Engineering)

1989-07-01T23:59:59.000Z

314

Anomalous Quantum Interference Induced by Landau-Zener Transitions in a Strongly Driven rf-SQUID Qubit  

E-Print Network (OSTI)

We irradiated an rf-SQUID qubit with large-amplitude and high frequency electromagnetic field. Population transitions between macroscopic distinctive quantum states due to Landau-Zener transitions at energy-level avoided crossings were observed. The qubit population on the excited states as a function of flux detuning and microwave power exhibits interference patterns. Some novel features are found in the interference and a model based on rate equations can well address the features.

Wang, Yiwen; Wen, Xueda; Pan, Cheng; Sun, Guozhu; Chen, Jian; Kang, Lin; Xu, Weiwei; Yu, Yang; Wu, Peiheng

2009-01-01T23:59:59.000Z

315

Experimental astrophysics with high power lasers and Z pinches  

SciTech Connect

With the advent of high energy density (HED) experimental facilities, such as high-energy lasers and fast Z-pinch, pulsed-power facilities, mm-scale quantities of matter can be placed in extreme states of density, temperature, and/or velocity. This has enabled the emergence of a new class of experimental science, HED laboratory astrophysics, wherein the properties of matter and the processes that occur under extreme astrophysical conditions can be examined in the laboratory. Areas particularly suitable to this class of experimental astrophysics include the study of opacities relevant to stellar interiors; equations of state relevant to planetary interiors; strong shock driven nonlinear hydrodynamics and radiative dynamics, relevant to supernova explosions and subsequent evolution; protostellar jets and high Mach-number flows; radiatively driven molecular clouds and nonlinear photoevaporation front dynamics; and photoionized plasmas relevant to accretion disks around compact objects, such as black holes and neutron stars.

Remington, B A; Drake, R P; Ryutov, D D

2004-12-10T23:59:59.000Z

316

rf improvements for Spallation Neutron Source H ion source  

Science Conference Proceedings (OSTI)

The Spallation Neutron Source at Oak Ridge National Laboratory is ramping up the accelerated proton beam power to 1.4 MW and just reached 1 MW. The rf-driven multicusp ion source that originates from the Lawrence Berkeley National Laboratory has been delivering 38 mA H beam in the linac at 60 Hz, 0.9 ms. To improve availability, a rf-driven external antenna multicusp ion source with a water-cooled ceramic aluminum nitride AlN plasma chamber is developed. Computer modeling and simulations have been made to analyze and optimize the rf performance of the new ion source. Operational statistics and test runs with up to 56 mA medium energy beam transport beam current identify the 2 MHz rf system as a limiting factor in the system availability and beam production. Plasma ignition system is under development by using a separate 13 MHz system. To improve the availability of the rf power system with easier maintenance, we tested a 70 kV isolation transformer for the 80 kW, 6% duty cycle 2 MHz amplifier to power the ion source from a grounded solid-state amplifier. 2010 American Institute of Physics.

Kang, Yoon W [ORNL; Fuja, Raymond E [ORNL; Goulding, Richard Howell [ORNL; Hardek, Thomas W [ORNL; Lee, Sung-Woo [ORNL; McCarthy, Mike [ORNL; Piller, Chip [ORNL; Shin, Ki [ORNL; Stockli, Martin P [ORNL; Welton, Robert F [ORNL

2010-01-01T23:59:59.000Z

317

Solar radiation powered battery reclaimer and charger  

SciTech Connect

A solar powered battery reclaiming and charging circuit is provided having a high frequency section (a bistable multi-vibrator, relaxation blocking bistable multi-vibrator or an oscillator inverter circuit) which is solar powered and output coupled by a close coupled RF transformer to the battery connected output section. The transformer has a secondary winding producing a current-voltage full wave output sharply defined through a two diode rectifying circuit to a multi-frequency 10 KHz to 100 KHz pulse output. The sharp pulse outputs with RF content in the 2--10 megahertz frequency range have specific frequencies equal to natural resonant frequencies of the specific electrolytes used in respective batteries. These resulting high frequency RF output signals in each pulse envelope structure are capable of reclaiming, maintaining and charging batteries that possess a liquid electrolyte or jell electrolyte and are beneficial to dry cell batteries as well in extending battery life. 9 figs.

Gali, C.E.

1994-01-04T23:59:59.000Z

318

Analysis of High Power IGBT Short Circuit Failures  

SciTech Connect

The Next Linear Collider (NLC) accelerator proposal at SLAC requires a highly efficient and reliable, low cost, pulsed-power modulator to drive the klystrons. A solid-state induction modulator has been developed at SLAC to power the klystrons; this modulator uses commercial high voltage and high current Insulated Gate Bipolar Transistor (IGBT) modules. Testing of these IGBT modules under pulsed conditions was very successful; however, the IGBTs failed when tests were performed into a low inductance short circuit. The internal electrical connections of a commercial IGBT module have been analyzed to extract self and mutual partial inductances for the main current paths as well as for the gate structure. The IGBT module, together with the partial inductances, has been modeled using PSpice. Predictions for electrical paths that carry the highest current correlate with the sites of failed die under short circuit tests. A similar analysis has been carried out for a SLAC proposal for an IGBT module layout. This paper discusses the mathematical model of the IGBT module geometry and presents simulation results.

Pappas, G.

2005-02-11T23:59:59.000Z

319

Conductor requirements for high-temperature superconducting utility power transformers  

Science Conference Proceedings (OSTI)

High-temperature superconducting (HTS) coated conductors in utility power transformers must satisfy a set of operating requirements that are driven by two major considerations-HTS transformers must be economically competitive with conventional units, and the conductor must be robust enough to be used in a commercial manufacturing environment. The transformer design and manufacturing process will be described in order to highlight the various requirements that it imposes on the HTS conductor. Spreadsheet estimates of HTS transformer costs allow estimates of the conductor cost required for an HTS transformer to be competitive with a similarly performing conventional unit.

Pleva, E. F. [Waukesha Electric Systems, Waukesha, WI; Mehrotra, V. [Waukesha Electric Systems, Waukesha, WI; Schwenterly, S W [ORNL

2010-01-01T23:59:59.000Z

320

Organic nonlinear crystals and high power frequency conversion  

SciTech Connect

We are searching for a new second- and third-harmonic generators among the salts of chiral organic acids and bases. We discuss the relevant properties of crystals from this group of compounds, including their nonlinear and phasematching characteristics, linear absorption, damage threshold and crystal growth. In addition, we summarize what is known concerning other nonlinear optical properties of these crystals, such as two-photon absorption, nonlinear refractive index, and stimulated Raman thresholds. A preliminary assessment is made of the potential of these materials for use in future high power, large aperture lasers such as those used for inertial confinement fusion experiments. 14 refs., 1 fig., 3 tabs.

Velsko, S.P.; Davis, L.; Wang, F.; Monaco, S.; Eimerl, D.

1987-12-01T23:59:59.000Z

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321

High-power radio-frequency attenuation device  

DOE Patents (OSTI)

A resistor device for attenuating radio frequency power includes a radio frequency conductor connected to a series of fins formed of high relative magnetic permeability material. The fins are dimensional to accommodate the skin depth of the current conduction therethrough, as well as an inner heat conducting portion where current does not travel. Thermal connections for air or water cooling are provided for the inner heat conducting portions of each fin. Also disclosed is a resistor device to selectively alternate unwanted radio frequency energy in a resonant cavity.

Kerns, Q.A.; Miller, H.W.

1981-12-30T23:59:59.000Z

322

High-power pulse modulator with ignitron discharger  

SciTech Connect

The high-power pulse modulator described here is used to produce spatial gaseous discharges and has an improved, controllable charging circuit, which permits a type ITR-4 ignitron discharger to be employed in a frequency mode as the basic commutator. The modulator is utilized in two modes: at a pulse repetition frequency of 50 Hz pulses are formed that have a duration of 25 usec and energies up to 3.5 kJ and at a frequency of 200 Hz, the pulses have a duration of -2 usec and energies up to 600 J. In all conditions the modulator operated stably with a wide range of load changes.

Anisimova, T.E.; Akkuratov, E.V.; Artemov, V.A.; Gromovenko, V.M.; Kalinin, V.P.; Nikonov, V.P.

1985-10-01T23:59:59.000Z

323

High-Voltage Power Supply System for Laser Isotope Separation  

SciTech Connect

This report presents several concepts for Laser High-Voltage Power Supply (HVPS) Systems for a Laser Isotope Separation facility. Selection of equipments and their arrangement into operational systems is based on proven designs and on application concepts now being developed. This report has identified a number of alternative system arrangements and has provided preliminary cost estimates for each. The report includes a recommendation for follow-on studies that will further define the optimum Laser HVPS Systems. Brief descriptions are given of Modulator/Regulator circuit trade-offs, system control interfaces, and their impact on costs.

Ketaily, E.C.; Buckner, R.P.; Uhrik, R.L.

1979-06-26T23:59:59.000Z

324

Technology survey and performance scaling for the design of high power nuclear electric power and propulsion systems.  

E-Print Network (OSTI)

??High power nuclear electric propulsion systems have the capability to enable many next-generation space exploration applications. To date, use of electric primary propulsion in flight… (more)

White, Daniel B., Jr

2011-01-01T23:59:59.000Z

325

Computer Study of Isotope Production in High Power Accelerators  

E-Print Network (OSTI)

Methods for radionuclide production calculation in a high power proton accelerator have been developed and applied to study production of 22 isotopes by high-energy protons and neutrons. These methods are readily applicable to accelerator, and reactor, environments other than the particular model we considered and to the production of other radioactive and stable isotopes. We have also developed methods for evaluating cross sections from a wide variety of sources into a single cross section set and have produced an evaluated library covering about a third of all natural elements. These methods also are applicable to an expanded set of reactions. A 684 page detailed report on this study, with 37 tables and 264 color figures is available on the Web at http://t2.lanl.gov/publications/publications.html, or, if not accessible, in hard copy from the authors.

Van Riper, K A; Wilson, W B

1999-01-01T23:59:59.000Z

326

Computer Study of Isotope Production in High Power Accelerators  

E-Print Network (OSTI)

Methods for radionuclide production calculation in a high power proton accelerator have been developed and applied to study production of 22 isotopes by high-energy protons and neutrons. These methods are readily applicable to accelerator, and reactor, environments other than the particular model we considered and to the production of other radioactive and stable isotopes. We have also developed methods for evaluating cross sections from a wide variety of sources into a single cross section set and have produced an evaluated library covering about a third of all natural elements. These methods also are applicable to an expanded set of reactions. A 684 page detailed report on this study, with 37 tables and 264 color figures is available on the Web at http://t2.lanl.gov/publications/publications.html, or, if not accessible, in hard copy from the authors.

K. A. Van Riper; S. G. Mashnik; W. B. Wilson

1999-01-25T23:59:59.000Z

327

Pushing the Limits of RF Superconductivity Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

Presentations Workshop Proceedings Suggested Reading Material on RF Superconductivity Workshop Dinner Accommodations Ground Transportation Access to...

328

High voltage power supply with modular series resonant inverters  

DOE Patents (OSTI)

A relatively small and compact high voltage, high current power supply for a laser utilizes a plurality of modules containing series resonant half bridge inverters. A pair of reverse conducting thyristors are incorporated in each series resonant inverter module such that the series resonant inverter modules are sequentially activated in phases 360.degree./n apart, where n=number of modules for n>2. Selective activation of the modules allows precise output control reducing ripple and improving efficiency. Each series resonant half bridge inverter module includes a transformer which has a cooling manifold for actively circulating a coolant such as water, to cool the transformer core as well as selected circuit elements. Conductors connecting and forming various circuit components comprise hollow, electrically conductive tubes such as copper. Coolant circulates through the tubes to remove heat. The conductive tubes act as electrically conductive lines for connecting various components of the power supply. Where it is desired to make electrical isolation breaks, tubes comprised of insulating material such as nylon are used to provide insulation and continue the fluid circuit.

Dreifuerst, Gary R. (Livermore, CA); Merritt, Bernard T. (Livermore, CA)

1995-01-01T23:59:59.000Z

329

High voltage power supply with modular series resonant inverters  

DOE Patents (OSTI)

A relatively small and compact high voltage, high current power supply for a laser utilizes a plurality of modules containing series resonant half bridge inverters. A pair of reverse conducting thyristors are incorporated in each series resonant inverter module such that the series resonant inverter modules are sequentially activated in phases 360{degree}/n apart, where n=number of modules for n>2. Selective activation of the modules allows precise output control reducing ripple and improving efficiency. Each series resonant half bridge inverter module includes a transformer which has a cooling manifold for actively circulating a coolant such as water, to cool the transformer core as well as selected circuit elements. Conductors connecting and forming various circuit components comprise hollow, electrically conductive tubes such as copper. Coolant circulates through the tubes to remove heat. The conductive tubes act as electrically conductive lines for connecting various components of the power supply. Where it is desired to make electrical isolation breaks, tubes comprised of insulating material such as nylon are used to provide insulation and continue the fluid circuit. 11 figs.

Dreifuerst, G.R.; Merritt, B.T.

1995-07-18T23:59:59.000Z

330

Performance limits of RF power CMOS  

E-Print Network (OSTI)

Wireless and mobile communication systems have become ubiquitous in our daily life. The need for higher bandwidth and thus higher speed and data rates in wireless communications has prompted the exploration of millimeter-wave ...

Gogineni, Usha, 1975-

2011-01-01T23:59:59.000Z

331

RF-Plasma Source Commissioning in Indian Negative Ion Facility  

Science Conference Proceedings (OSTI)

The Indian program of the RF based negative ion source has started off with the commissioning of ROBIN, the inductively coupled RF based negative ion source facility under establishment at Institute for Plasma research (IPR), India. The facility is being developed under a technology transfer agreement with IPP Garching. It consists of a single RF driver based beam source (BATMAN replica) coupled to a 100 kW, 1 MHz RF generator with a self excited oscillator, through a matching network, for plasma production and ion extraction and acceleration. The delivery of the RF generator and the RF plasma source without the accelerator, has enabled initiation of plasma production experiments. The recent experimental campaign has established the matching circuit parameters that result in plasma production with density in the range of 0.5-1x10{sup 18}/m{sup 3}, at operational gas pressures ranging between 0.4-1 Pa. Various configurations of the matching network have been experimented upon to obtain a stable operation of the set up for RF powers ranging between 25-85 kW and pulse lengths ranging between 4-20 s. It has been observed that the range of the parameters of the matching circuit, over which the frequency of the power supply is stable, is narrow and further experiments with increased number of turns in the coil are in the pipeline to see if the range can be widened. In this paper, the description of the experimental system and the commissioning data related to the optimisation of the various parameters of the matching network, to obtain stable plasma of required density, are presented and discussed.

Singh, M. J.; Bandyopadhyay, M.; Yadava, Ratnakar; Chakraborty, A. K. [ITER- India, Institute for Plasma Research, A-29, Sector 25, GIDC, Gandhinagar, Gujrat (India); Bansal, G.; Gahlaut, A.; Soni, J.; Kumar, Sunil; Pandya, K.; Parmar, K. G.; Sonara, J. [Institute for Plasma Research, Bhat Gandhinagar, Gujrat (India); Kraus, W.; Heinemann, B.; Riedl, R.; Obermayer, S.; Martens, C.; Franzen, P.; Fantz, U. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany)

2011-09-26T23:59:59.000Z

332

RF system models for the CERN Large Hadron Collider with application to longitudinal dynamics  

Science Conference Proceedings (OSTI)

The LHC RF station-beam interaction strongly influences the longitudinal beam dynamics, both single bunch and collective effects. Non-linearities and noise generated within the Radio Frequency (RF) accelerating system interact with the beam and contribute to beam motion and longitudinal emittance blowup. Thus, the noise power spectrum of the RF accelerating voltage strongly affects the longitudinal beam distribution. Furthermore, the coupled-bunch instabilities are also directly affected by the RF components and the configuration of the Low Level RF (LLRF) feedback loops. In this work we present a formalism relating the longitudinal beam dynamics with the RF system configurations, an estimation of collective effects stability margins, and an evaluation of longitudinal sensitivity to various LLRF parameters and configurations.

Mastorides, T.; Rivetta, C.; Fox, J.D.; Winkle, D.Van; /SLAC; Baudrenghien, P.; /CERN

2011-03-03T23:59:59.000Z

333

High Power, High Voltage FETs in Linear Applications: A User's Perspective  

SciTech Connect

The specifications of the current crop of highpower, high-voltage field-effect transistors (FETs) can lure a designer into employing them in high-voltage DC equipment. Devices with extremely low on-resistance and very high power ratings are available from several manufacturers. However, our experience shows that high-voltage, linear operation of these devices at near-continuous duty can present difficult reliability challenges at stress levels well-below their published specifications. This paper chronicles the design evolution of a 600 volt, 8 ampere shunt regulator for use with megawatt-class radio transmitters, and presents a final design that has met its reliability criteria.

N. Greenough, E. Fredd, S. DePasquale

2009-09-21T23:59:59.000Z

334

HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER  

DOE Green Energy (OSTI)

OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from fossil fuels has trace contaminants (primarily carbon monoxide) that are detrimental to precious metal catalyzed fuel cells, as is now recognized by many of the world's largest automobile companies. Thermochemical hydrogen will not contain carbon monoxide as an impurity at any level. Electrolysis, the alternative process for producing hydrogen using nuclear energy, suffers from thermodynamic inefficiencies in both the production of electricity and in electrolytic parts of the process. The efficiency of electrolysis (electricity to hydrogen) is currently about 80%. Electric power generation efficiency would have to exceed 65% (thermal to electrical) for the combined efficiency to exceed the 52% (thermal to hydrogen) calculated for one thermochemical cycle. Thermochemical water-splitting cycles have been studied, at various levels of effort, for the past 35 years. They were extensively studied in the late 70s and early 80s but have received little attention in the past 10 years, particularly in the U.S. While there is no question about the technical feasibility and the potential for high efficiency, cycles with proven low cost and high efficiency have yet to be developed commercially. Over 100 cycles have been proposed, but substantial research has been executed on only a few. This report describes work accomplished during a three-year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.'' The emphasis of the first phase was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen from water in which the primary energy input is high temperature heat from an advanced nuclear reactor and to select one (or, at most three) for further detailed consideration. During Phase 1, an exhaustive literature search was performed to locate all cycles previously proposed. The cycles located were screened using objective criteria to determine which could benefit, in terms of efficien

BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

2003-06-01T23:59:59.000Z

335

HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER  

SciTech Connect

OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from fossil fuels has trace contaminants (primarily carbon monoxide) that are detrimental to precious metal catalyzed fuel cells, as is now recognized by many of the world's largest automobile companies. Thermochemical hydrogen will not contain carbon monoxide as an impurity at any level. Electrolysis, the alternative process for producing hydrogen using nuclear energy, suffers from thermodynamic inefficiencies in both the production of electricity and in electrolytic parts of the process. The efficiency of electrolysis (electricity to hydrogen) is currently about 80%. Electric power generation efficiency would have to exceed 65% (thermal to electrical) for the combined efficiency to exceed the 52% (thermal to hydrogen) calculated for one thermochemical cycle. Thermochemical water-splitting cycles have been studied, at various levels of effort, for the past 35 years. They were extensively studied in the late 70s and early 80s but have received little attention in the past 10 years, particularly in the U.S. While there is no question about the technical feasibility and the potential for high efficiency, cycles with proven low cost and high efficiency have yet to be developed commercially. Over 100 cycles have been proposed, but substantial research has been executed on only a few. This report describes work accomplished during a three-year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.'' The emphasis of the first phase was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen from water in which the primary energy input is high temperature heat from an advanced nuclear reactor and to select one (or, at most three) for further detailed consideration. During Phase 1, an exhaustive literature search was performed to locate all cycles previously proposed. The cycles located were screened using objective criteria to determine which could

BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

2003-06-01T23:59:59.000Z

336

RF Micro Devices Inc RFMD | Open Energy Information  

Open Energy Info (EERE)

RF Micro Devices Inc RFMD RF Micro Devices Inc RFMD Jump to: navigation, search Name RF Micro Devices, Inc. (RFMD) Place Greensboro, North Carolina Zip 27409-9421 Product RF Micro Devices, Inc. is a global leader in the design and manufacture of high-performance semiconductor components. Coordinates 44.576059°, -72.294016° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":44.576059,"lon":-72.294016,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

337

A Scheduling Algorithm for Consistent Monitoring Results with Solar Powered High-Performance Wireless Embedded Systems  

E-Print Network (OSTI)

A Scheduling Algorithm for Consistent Monitoring Results with Solar Powered High but critical task for solar powered wireless high power embedded systems. Our algorithm relies on an energy Few bytes per second Up to 2MB per second Peak power (mW) 198 2200 Solar harvesting is one of the most

Simunic, Tajana

338

High-power ion-cyclotron-resonance heating in the Wisconsin Levitated Octupole  

DOE Green Energy (OSTI)

Ion cyclotron resonance heating has been investigated, both experimentally and theoretically, on the Wisconsin Levitated Octupole. Heating of both ions and electrons has been observed. Typically, a two component ion energy distribution is produced (300 eV and 50 eV) with the application of 500 kW of rf power into a 5 x 10/sup 12/ cm/sup -3/ density plasma. Power is coupled to the plasma with an antenna that also serves as the inductor of an oscillator tank circuit. The oscillator is tunable from 1 to 3 MHz and can be applied for periods up to 10 msec. The experiments were performed with hydrogen, gun injected plasmas.

Fortgang, C.M.

1983-05-01T23:59:59.000Z

339

Development of high-power gyrotrons with gradually tapered cavity  

Science Conference Proceedings (OSTI)

In high power gyrotrons, the parasitic modes coupled with the operating mode cannot be avoided in the beam-wave interaction. These parasitic modes will decrease the efficiency of the gyrotrons. The purity of the operating mode affected by different tapers should be carefully studied. The steady-state self-consistent nonlinear theory for gyrotron with gradually tapered cavity is developed in this paper. A steady-state calculation code including 'cold cavity' and 'hot cavity' is designed. By comparison, a time-domain model analysis of gyrotron operation is also studied by particle-in-cell (PIC). It is found that the tapers of gyrotron have different influences on the modes coupling between the operating mode and the parasitic modes. During the study, an example of 94 GHz gyrotron with pure operating mode TE{sub 03} has been designed. The purity of the operating mode in the optimized cavity is up to -77 dB, and in output waveguide of the cavity is up to -76 dB. At the same time, the beam-wave interaction in the designed cavity has been simulated, too. An output power of 120 kW, corresponding to 41.6% efficiency and an oscillation frequency of 94.099 GHz have been achieved with a 50 kV, 6 A helical electron beam at a guiding magnetic field of 3.5485 T. The results show that the power in spurious modes of the optimized cavity may be kept far below than that of the traditional tapered cavity.

Lei Chaojun [Terahertz Science and Technology Research Center, University of Electronics Science and Technology of China, Chengdu 610054 (China); The Chinese People's Armed Police Force Academy, Langfang 065000 (China); Yu Sheng; Niu Xinjian; Liu Yinghui; Li Hongfu; Li Xiang [Terahertz Science and Technology Research Center, University of Electronics Science and Technology of China, Chengdu 610054 (China)

2012-12-15T23:59:59.000Z

340

High Power Testing of X-Band Dielectric-Loaded Accelerating Structures  

NLE Websites -- All DOE Office Websites (Extended Search)

m-to-metal-to-dielectric in a region of high electric field that is expected to cause breakdown problems; and (2) high power density in the dielectric, since all the power passes...

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

The Development of low cost LiFePO4-based high power lithium...  

NLE Websites -- All DOE Office Websites (Extended Search)

Development of low cost LiFePO4-based high power lithium-ion batteries Title The Development of low cost LiFePO4-based high power lithium-ion batteries Publication Type Journal...

342

Development of a high-power lithium-ion battery.  

DOE Green Energy (OSTI)

Safety is a key concern for a high-power energy storage system such as will be required in a hybrid vehicle. Present lithium-ion technology, which uses a carbon/graphite negative electrode, lacks inherent safety for two main reasons: (1) carbon/graphite intercalates lithium at near lithium potential, and (2) there is no end-of-charge indicator in the voltage profile that can signal the onset of catastrophic oxygen evolution from the cathode (LiCoO{sub 2}). Our approach to solving these safety/life problems is to replace the graphite/carbon negative electrode with an electrode that exhibits stronger two-phase behavior further away from lithium potential, such as Li{sub 4}Ti{sub 5}O{sub 12}. Cycle-life and pulse-power capability data are presented in accordance with the Partnership for a New Generation of Vehicles (PNGV) test procedures, as well as a full-scale design based on a spreadsheet model.

Jansen, A. N.

1998-09-02T23:59:59.000Z

343

HIGH FREQUENCY POWER TRANSMISSION LINE FOR CYCLOTRONS AND THE LIKE  

DOE Patents (OSTI)

High-frequency power transmission systems, particularly a stacked capacitance alternating power current transmission line wherein maximum utilization of the effective conductios skin of the line conductors is achieved while enabling a low impedance to be obtained are reported. The transmission line consists of a number of flat metal strips with interleaved dielectric strips. The metal dielectric strips are coiled spirally with the axis of the spiral extending along the length of the strips, and the alternating metal strips at the output end have outwardly extending aligned lugs which are directly strapped together and connected to the respective terminals on the load. At the input end of the transmission line, similarly, the alternate metal strips are directly strapped together and connected to an altereating current source. With the arrangement described each metal strip conducts on both sides, so that the metal strips are designed to have a thickness corresponding to twice the depth of the "skin effect" conducting lamina of each conductor at the source frequency.

Armstrong, W.J.

1954-04-20T23:59:59.000Z

344

Application of High Powered Lasers to Perforated Completions  

NLE Websites -- All DOE Office Websites (Extended Search)

Congress on Applications of Laser & Electro-Optics Congress on Applications of Laser & Electro-Optics October 13 - 16, 2003, Jacksonville, Florida Application of High Powered Lasers to Perforated Completions Zhiyue Xu, Claude B. Reed and Keng H. Leong Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 R. A. Parker Parker Geoscience Consulting, LLC, 6346 Secrest Street, Arvada, CO 80403 R. M. Graves, Petroleum Engineering Department, Colorado School of Mines, Golden, CO 80401 ABSTRACT As part of the process of drilling an oil or gas well, a steel production casing is often inserted to the bottom of the well and sealed with cement against the productive formation. Openings must be made through the steel casing wall and cement and into the rock formation to allow formation fluid to enter the well. Conventionally, a perforator is

345

CENTER FOR PULSED POWER DRIVEN HIGH ENERGY DENSITY PLASMA STUDIES  

SciTech Connect

This annual report summarizes the activities of the Cornell Center for Pulsed-Power-Driven High-Energy-Density Plasma Studies, for the 12-month period October 1, 2005-September 30, 2006. This period corresponds to the first year of the two-year extension (awarded in October, 2005) to the original 3-year NNSA/DOE Cooperative Agreement with Cornell, DE-FC03-02NA00057. As such, the period covered in this report also corresponds to the fourth year of the (now) 5-year term of the Cooperative Agreement. The participants, in addition to Cornell University, include Imperial College, London (IC), the University of Nevada, Reno (UNR), the University of Rochester (UR), the Weizmann Institute of Science (WSI), and the P.N. Lebedev Physical Institute (LPI), Moscow. A listing of all faculty, technical staff and students, both graduate and undergraduate, who participated in Center research activities during the year in question is given in Appendix A.

Professor Bruce R. Kusse; Professor David A. Hammer

2007-04-18T23:59:59.000Z

346

Power efficiency for very high temperature solar thermal cavity receivers  

DOE Patents (OSTI)

This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positioned in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts infrared radiation from the front of the absorber. With this arrangement, a high percentage of the solar power input is retained in the cavity; thus, high internal temperatures are attained.

McDougal, Allan R. (LaCanada-Flintridge, CA); Hale, Robert R. (Upland, CA)

1984-01-01T23:59:59.000Z

347

R.F. heating near the lower hybrid frequency in the FM-1 spherator  

SciTech Connect

Plasma heating experiments at frequencies near the lower hybrid frequency have been carried out at modest powers (.05 to 4kW). The antenna structure operating at 68 MHz was comprised of two plates driven out of phase on the exterior of the plasma. High electron heating efficiency (greater than 40 percent) in both helium and argon plasmas was observed with only a weak density dependence. At low densities (n/sub e/ less than or equal to 1 x 10$sup 11$ cm$sup -3$), the heating was uniform across the plasma while at higher densities the heating was preferentially on the exterior portion of the plasma. The heating of the exterior of the plasma was found not to correspond to absorption at the lower hybrid resonance layer. The electron heating efficiency was found to be a weak function of rf power when the incident rf power was varied from 1 to 15 times the experimentally observed threshold power for parametric instabilities. Ion temperatures were determined by measuring the Doppler broadening of an Argon ion line using a Fabry-Perot interferometer. Low efficiency main body ion heating (1 to 3 percent) was observed. (auth)

Hawryluk, R.J.; Davis, S.L.; Schmidt, J.A.

1975-12-01T23:59:59.000Z

348

Hefei Guoxuan High tech Power Energy Co Ltd | Open Energy Information  

Open Energy Info (EERE)

Guoxuan High tech Power Energy Co Ltd Guoxuan High tech Power Energy Co Ltd Jump to: navigation, search Name Hefei Guoxuan High-tech Power Energy Co, Ltd Place China Sector Solar Product Anhui Province - based researcher and manufacturer focused on cathode material production for lithium batteries, production of the batteries themselves and of products such as solar powered lights and e-bikes. References Hefei Guoxuan High-tech Power Energy Co, Ltd[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Hefei Guoxuan High-tech Power Energy Co, Ltd is a company located in China . References ↑ "Hefei Guoxuan High-tech Power Energy Co, Ltd" Retrieved from "http://en.openei.org/w/index.php?title=Hefei_Guoxuan_High_tech_Power_Energy_Co_Ltd&oldid=346428

349

High-density thermoelectric power generation and nanoscale thermal metrology  

E-Print Network (OSTI)

Thermoelectric power generation has been around for over 50 years but has seen very little large scale implementation due to the inherently low efficiencies and powers available from known materials. Recent material advances ...

Mayer, Peter (Peter Matthew), 1978-

2007-01-01T23:59:59.000Z

350

Timing driven power gating in high-level synthesis  

Science Conference Proceedings (OSTI)

The power gating technique is useful in reducing standby leakage current, but it increases the gate delay. For a functional unit, its maximum allowable delay (for a target clock period) limits the smallest standby leakage current its power gating can ...

Shih-Hsu Huang; Chun-Hua Cheng

2009-01-01T23:59:59.000Z

351

Investigation of Catastrophic Failures in High-Power MOSFET ...  

Science Conference Proceedings (OSTI)

Tube Failure in Coal and Gas Fired Power Plant · Understanding Failure of Titanium Alloys Using Fractography and Other Characterization Methods.

352

High power linear pulsed beam annealer. [Patent application  

DOE Patents (OSTI)

A high power pulsed electron beam system for annealing semiconductors is comprised of an electron gun having a heated cathode, control grid and focus ring for confining the pulsed beam of electrons to a predetermined area, and a curved drift tube. The drift tube and an annular Faraday shield between the focus ring and the drift tube are maintained at a high positive voltage with respect to the cathode to accelerate electrons passing through the focus ring, thereby eliminating space charge limitations on the emission of electrons from said gun. A coil surrounding the curved drift tube provides a magnetic field which maintains the electron beam focused about the axis of the tube. The magnetic field produced by the coil around the curved tube imparts motion to electrons in a spiral path for shallow penetration of the electrons into a target. It also produces a scalloped profile of the electron beam. A second drift tube spaced a predetermined distance from the curved tube is positioned with its axis aligned with the axis of the first drift tube. The second drift tube and the target holder are maintained at a reference voltage between the cathode voltage and the curved tube voltage to decelerate the electrons. A second coil surrounding the second drift tube, maintains the electron beam focused about the axis of the second drift tube. The magnetic field of the second coil comprises the electron beam to the area of the semiconductor on the target holder.

Strathman, M.D.; Sadana, D.K.; True, R.B.

1980-11-26T23:59:59.000Z

353

Inductive current startup in large tokamaks with expanding minor radius and rf assist  

Science Conference Proceedings (OSTI)

Auxiliary rf heating of electrons before and during the current-rise phase of a large tokamak, such as the Fusion Engineering Device (R = 4.8 m, a = 1.3 m, sigma = 1.6, B/sub T/ = 3.62 T), is examined as a means of reducing both the initiation loop voltage and resistive flux expenditure during startup. Prior to current initiation, 1 to 2 MW of electron cyclotron resonance heating power at approx. 90 GHz is used to create a small volume of high conductivity plasma (T/sub e/ approx. = 100 eV, n/sub e/ approx. = 10/sup 19/ m/sup -3/) near the upper hybrid resonance (UHR) region. This plasma conditioning permits a small radius (a/sub 0/ approx. = 0.2 to 0.4 m) current channel to be established with a relatively low initial loop voltage (less than or equal to 25 V as opposed to approx. 100 V without rf assist). During the subsequent plasma expansion and current ramp phase, a combination of rf heating (up to 5 MW) and current profile control leads to a substantial savings in volt-seconds by: (1) minimizing the resistive flux consumption; and (2) maintaining the internal flux at or near the flat profile limit.

Borowski, S.K.

1984-02-01T23:59:59.000Z

354

Coal-fired high performance power generating system  

SciTech Connect

The goals of the program are to develop a coal-fired high performance power generation system (HIPPS) by the year 2000 that is capable of > 47% thermal efficiency; NO[sub x] SO [sub x] and Particulates < 25% NSPS; Cost of electricity 10% lower; coal > 65% of heat input and all solid wastes benign. In order to achieve these goals our team has outlined a research plan based on an optimized analysis of a 250 MW[sub e] combined cycle system applicable to both frame type and aeroderivative gas turbines. Under the constraints of the cycle analysis we have designed a high temperature advanced furnace (HITAF) which integrates several combustor and air heater designs with appropriate ash management procedures. Most of this report discusses the details of work on these components, and the R D Plan for future work. The discussion of the combustor designs illustrates how detailed modeling can be an effective tool to estimate NO[sub x] production, minimum burnout lengths, combustion temperatures and even particulate impact on the combustor walls. When our model is applied to the long flame concept it indicates that fuel bound nitrogen will limit the range of coals that can use this approach. For high nitrogen coals a rapid mixing, rich-lean, deep staging combustor will be necessary. The air heater design has evolved into two segments: a convective heat exchanger downstream of the combustion process; a radiant panel heat exchanger, located in the combustor walls; The relative amount of heat transferred either radiatively or convectively will depend on the combustor type and the ash properties.

1992-07-01T23:59:59.000Z

355

A computer program for HVDC converter station RF noise calculations  

SciTech Connect

HVDC converter station operations generate radio frequency (RF) electromagnetic (EM) noise which could interfere with adjacent communication and computer equipment, and carrier system operations. A generic Radio Frequency Computer Analysis Program (RAFCAP) for calculating the EM noise generated by valve ignition of a converter station has been developed as part of a larger project. The program calculates RF voltages, currents, complex power, ground level electric field strength and magnetic flux density in and around an HVDC converter station. The program requires the converter station network to be represented by frequency dependent impedance functions. Comparisons of calculated and measured values are given for an actual HVDC station to illustrate the validity of the program. RAFCAP is designed to be used by engineers for the purpose of calculating the RF noise produced by the igniting of HVDC converter valves.

Kasten, D.G.; Caldecott, R.; Sebo, S.A. (Ohio State Univ., Columbus, OH (United States). Dept. of Electrical Engineering); Liu, Y. (Virginia Polytechnic Inst. State Univ., Blacksburg, VA (United States). Bradley Dept. of Electrical Engineering)

1994-04-01T23:59:59.000Z

356

Magnet Technology for Power Converters: Nanocomposite Magnet Technology for High Frequency MW-Scale Power Converters  

Science Conference Proceedings (OSTI)

Solar ADEPT Project: CMU is developing a new nanoscale magnetic material that will reduce the size, weight, and cost of utility-scale PV solar power conversion systems that connect directly to the grid. Power converters are required to turn the energy that solar power systems create into useable energy for the grid. The power conversion systems made with CMU’s nanoscale magnetic material have the potential to be 150 times lighter and significantly smaller than conventional power conversion systems that produce similar amounts of power.

None

2012-02-27T23:59:59.000Z

357

Space reactor/Stirling cycle systems for high power Lunar applications  

DOE Green Energy (OSTI)

NASA`s Space Exploration Initiative (SEI) has proposed the use of high power nuclear power systems on the lunar surface as a necessary alternative to solar power. Because of the long lunar night ({approximately} 14 earth days) solar powered systems with the requisite energy storage in the form of regenerative fuel cells or batteries becomes prohibitively heavy at high power levels ({approximately} 100 kWe). At these high power levels nuclear power systems become an enabling technology for variety of missions. One way of producing power on the lunar surface is with an SP-100 class reactor coupled with Stirling power converters. In this study, analysis and characterization of the SP-100 class reactor coupled with Free Piston Stirling Power Conversion (FPSPC) system will be performed. Comparison of results with previous studies of other systems, particularly Brayton and Thermionic, are made.

Schmitz, P.D. [Sverdrup Technology, Inc., Brook Park, OH (United States). Lewis Research Center Group; Mason, L.S. [National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center

1994-09-01T23:59:59.000Z

358

RF & Microwave Systems Group The RF & Microwave Systems  

E-Print Network (OSTI)

for Technology Transfer. Tagging, Tracking, and Locating Systems TTL technologies are on the verge and development (R&D) geared toward supplying robust communications for extreme environments; global tagging, tracking, and locating (TTL) systems; and RF- and microwave- based measurement and processing systems

359

X-Band Active-Passive Rf Pulse Compressor with Plasma Switches  

SciTech Connect

As proposed by SLAC, the efficiency of a pulse compressor of the SLED-II type could be increased by changing both the phase of the microwave source and the coupling coefficient of the delay line. In the existing SLED-II system at frequency 11.4 GHz, the resonant delay line is coupled with the source via an iris with a constant reflection coefficient. Replacement of the iris with an active component makes it possible to create an active SLED-II system. In this paper, the use of plasma switches as the active elements is discussed. Plasma switches have been developed and tested at a high-power level for production of flattop compressed pulses. Active switching of SLED-II has demonstrated a marked increase in efficiency (by 20%) and power gain (by 37%) as compared with passive switching. The active compressor has produced 173 ns rf flattop output pulses with a power of about 112 MW.

Vikharev, A.L.; Ivanov, O.A.; Gorbachev, A.M.; /Nizhnii Novgorod, IAP /Omega-P, New Haven; Lobaev, M.A.; Isaev, V.A.; /Nizhnii Novgorod, IAP; Tantawi, S.G.; Lewandowski, J.R.; /SLAC; Hirshfield, J.L.; /Omega-P, New Haven /Yale U.

2012-04-27T23:59:59.000Z

360

ANALYSIS OF A HIGH TEMPERATURE GAS-COOLED REACTOR POWERED HIGH TEMPERATURE ELECTROLYSIS HYDROGEN PLANT  

DOE Green Energy (OSTI)

An updated reference design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322°C and 750°C, respectively. The reactor heat is used to produce heat and electric power to the HTE plant. A Rankine steam cycle with a power conversion efficiency of 44.4% was used to provide the electric power. The electrolysis unit used to produce hydrogen includes 1.1 million cells with a per-cell active area of 225 cm2. The reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 42.8% at a hydrogen production rate of 1.85 kg/s (66 million SCFD) and an oxygen production rate of 14.6 kg/s (33 million SCFD). An economic analysis of this plant was performed with realistic financial and cost estimating The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a competitive cost. A cost of $3.03/kg of hydrogen was calculated assuming an internal rate of return of 10% and a debt to equity ratio of 80%/20% for a reactor cost of $2000/kWt and $2.41/kg of hydrogen for a reactor cost of $1400/kWt.

M. G. McKellar; E. A. Harvego; A. M. Gandrik

2010-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

A thermal analysis model for high power density beam stops  

SciTech Connect

The Lawrence Berkeley National Laboratory (LBNL) is presently designing and building the 2.5 MeV injector for the Spallation Neutron Source (SNS). The design includes various beam intercepting devices such as beam stops and slits. The target power densities can be as high as 500 kW/cm{sup 2} with a beam stopping range of 25 to 30 microns, producing stresses well above yield in most materials. In order to analyze the induced temperatures and stresses, a finite element model has been developed. The model has been written parametrically to allow the beam characteristics, target material, dimensions, angle of incidence and mesh densities to be easily adjusted. The heat load is applied to the model through the use of a 3-dimensional table containing the calculated volumetric heat rates. The load is based on a bi-gaussian beam shape which is absorbed by the target according to a Bragg peak distribution. The results of several analyses using the SNS Front End beam are presented.

Virostek, S.; Oshatz, D.; Staples, J.

2001-06-08T23:59:59.000Z

362

Design of a High Temperature Small Particle Solar Receiver for Powering a Gas Turbine Engine  

E-Print Network (OSTI)

Design of a High Temperature Small Particle Solar Receiver for Powering a Gas Turbine Engine Dr. Fletcher Miller SDSU Department of Mechanical Engineering Abstract Solar thermal power for electricity will describe the design of a high temperature solar receiver capable of driving a gas turbine for power

Ponce, V. Miguel

363

(USC) Power Plant Development and High Temperature Materials ...  

Science Conference Proceedings (OSTI)

For further improvement of thermal efficiency and decreasing CO2 emission China intents to develop the advanced USC power plant with the ...

364

Experiment Insertion in a High Power Test Reactor: Debra Utterbeck ...  

Science Conference Proceedings (OSTI)

Feb 27, 2012 ... Heat Generation Rate. • Fuel fission power density. – Thermal/Hydraulic. • Min. and max. temperatures as a function of gas gap/gas mixture.

365

High efficiency fuel cell/advanced turbine power cycles  

Science Conference Proceedings (OSTI)

The following figures are included: Westinghouse (W.) SOFC pilot manufacturing facility; cell scale-up plan; W. 25 kW SOFC unit at the utility`s facility on Rokko Island; pressure effect on SOFC power and efficiency; SureCELL{trademark} vs conventional gas turbine plants; SureCELL{trademark} product line for distributed power applications; 20 MW pressurized SOFC/gas turbine power plant; 10 MW SOFT/CT power plant; SureCELL{trademark} plant concept design requirements; and W. SOFC market entry.

Morehead, H.

1996-12-31T23:59:59.000Z

366

Nonlinearity Measurements of High-Power Laser Detectors at ...  

Science Conference Proceedings (OSTI)

... We have developed a system [3] for measuring the nonlinearity of the detectors over the 1 W to multi- kilowatt power range. ...

2011-10-03T23:59:59.000Z

367

Future High Voltage Silicon Carbide Power Devices Future ...  

Science Conference Proceedings (OSTI)

... PFC) in Switch Mode Power Supplies (SMPS) • Anti-Parallel rectifier in Motor Control • Boost Converter and Inverter Section for solar conversion ...

2013-04-20T23:59:59.000Z

368

High power bipolar battery/cells with enhanced overcharge tolerance  

SciTech Connect

A cell or battery of cells having improved overcharge tolerance and increased power capability, and methods for the construction of such cells or batteries, via electrolyte modification.

Kaun, Thomas D. (New Lenox, IL)

1998-01-01T23:59:59.000Z

369

Simulation of synchrotron motion with rf noise  

Science Conference Proceedings (OSTI)

The theoretical formulation is described that is behind an algorithm for synchrotron phase-space tracking with rf noise and some preliminary simulation results of bunch diffusion under rf noise obtained by actual tracking.

Leemann, B.T.; Forest, E.; Chattopadhyay, S.

1986-08-01T23:59:59.000Z

370

MSTC - Microsystems Science, Technology, and Components - RF...  

NLE Websites -- All DOE Office Websites (Extended Search)

band RF input and supplies N identical outputs (N4 or 8). SiGe, GaAs, GaN RFICs. Passive RF detectors - Pyroelectric microdetectors that produce a DC output proportional to...

371

Selective word reading for high performance and low power processor  

Science Conference Proceedings (OSTI)

In this paper, we propose Selective Word Reading (SWR) technique for a low power processor without a loss of performance. The development of this technique was motivated by the differences between store unit sizes per storage level. In typical cases, ... Keywords: cache architecture, cache controller, cache memory, low power, selective word, word-interleaved cache

Yun Kyo Cho; Seong Tae Jhang; Chu Shik Jhon

2011-11-01T23:59:59.000Z

372

High-power copper vapour lasers and applications  

Science Conference Proceedings (OSTI)

Expanded applications of copper vapor lasers has prompted increased demand for higher power and better beam quality. This paper reports recent progress in laser power scaling, MOPA operation, beam quality improvement, and applications in precision laser machining. Issues such as gas heating, radial delay, discharge instability, and window heating will also be discussed.

Chang, J.J.; Warner, B.E.; Boley, C.D.; Dragon, E.P.

1995-08-01T23:59:59.000Z

373

Power Efficiency in High Performance Computing Shoaib Kamil  

E-Print Network (OSTI)

of 192 cores per cabinet. The power feed to each cabinet is 208 VAC 3-phase and is capable of handling 25 KW per rack. Each cabinet has a single 92 percent efficient power supply at the bottom of the rack system performance (ssp) metric. LBNL Tech Report 58868, 2005. [13] L. Oliker, A. Canning, J. Carter, J

374

A high level power model for Network-on-Chip (NoC) router  

Science Conference Proceedings (OSTI)

This paper presents a high level power estimation methodology for a Network-on-Chip (NoC) router, that is capable of providing cycle accurate power profile to enable power exploration at system level. Our power macro model is based on the number of flits ... Keywords: Interconnection network, Multi-processor System-on-Chip (MPSoC), Network-on-Chip (NoC), Power model

Seung Eun Lee; Nader Bagherzadeh

2009-11-01T23:59:59.000Z

375

RF tests of an 805 MHz pillbox cavity at Lab G of Fermilab  

SciTech Connect

We report recent high power RF tests on an 805 MHz RF pillbox cavity with demountable windows for beam apertures at Lab G of Fermilab, a dedicated facility for testing of MUCOOL (muon cooling) components. The cavity is installed inside a superconducting solenoidal magnet. A 12 MW peak RF power klystron is used for the tests. The cavity has been processed both with and without magnetic field. Without magnetic field, a gradient of 34 MV/m was reached rather quickly with very low sparking rate. In a 2.5 T solenoidal field, a 16 MV/m gradient was achieved, and it had to take many weeks of conditioning. Strong multipacting effects associated with high radiation levels were measured during the processing with the magnetic field. More recently Be windows with TiN-coated surface have been installed and tested at conditions of with and without the external magnetic field. A conservative 16 MV/m gradient without magnetic field was reached quickly as planned. Less multipacting was observed during the conditioning, it indicated that the TiN-coated surface on the windows had indeed helped to reduce the secondary electron emissions significantly. A modest gradient of 16.5 MV/m was finally achieved with magnet on in solenoidal mode and the field up to 4 T. Preliminary inspection on Be windows surface found no damage at all, in comparison with Cu windows where substantial surface damage was found. Preliminary understanding of conditioning cavity in a strong magnetic field has been developed. More through window and cavity surface inspection is under way.

Li, Derun; Corlett, J.; MacGill, R.; Wallig, J.; Zisman, M.; Moretti, A.; Qian , Z.; Wu, V.; Rimmer, R.; Norem, J.; Torun, Y.

2003-05-01T23:59:59.000Z

376

A new rf structure for intermediate-velocity particles  

Science Conference Proceedings (OSTI)

This paper describes an rf structure with high shunt impedance and good field stability for particle velocities o.1 {le} {beta} {le} 0.5. Traditionally, the drift-tube linac (DTL) has been the structure of choice for this velocity range. The new structure, called a coupled-cavity drift-tube linac (CCDTL), combines features of the Alvarez DTL and the {pi}-mode coupled-cavity linac (CCL). Each accelerating cavity is a two-cell, 0-mode DTL. The center-to-center distance between gaps is {gamma}{lambda}. Adjacent accelerating cavities have oppositely directed electric fields, alternating in phase by 180{degrees}. The chain of cavities operates in a {pi}/2 structure mode so the coupling cavities are nominally unexcited. We will discuss 2-D and 3-D electromagnetic code calculations, and some initial measurements on a low-power model of a CCDTL. We will compare shunt impedance calculations for DTL, CCL, and CCDTL structures. The CCDTL has potential application for a wide range of ion linacs. For example, high-intensity proton linacs could use the CCDTL instead of a DTL up to an energy of about 200 MeV. Another example is a stand-alone, low-duty, low-current, very high gradient, proton, cancer therapy machine. The advantage for this application would be a saving in the cost of the machine because the linac would be short.

Billen, J.H.; Krawczyk, F.L.; Wood, R.L.; Young, L.M.

1994-09-01T23:59:59.000Z

377

Feasibility of producing a short, high energy s-band linear accelerator using a klystron power source  

SciTech Connect

Purpose: To use a finite-element method (FEM) model to study the feasibility of producing a short s-band (2.9985 GHz) waveguide capable of producing x-rays energies up to 10 MV, for applications in a linac-MR, as well as conventional radiotherapy. Methods: An existing waveguide FEM model developed by the authors' group is used to simulate replacing the magnetron power source with a klystron. Peak fields within the waveguide are compared with a published experimental threshold for electric breakdown. The RF fields in the first accelerating cavity are scaled, approximating the effect of modifications to the first coupling cavity. Electron trajectories are calculated within the RF fields, and the energy spectrum, beam current, and focal spot of the electron beam are analyzed. One electron spectrum is selected for Monte Carlo simulations and the resulting PDD compared to measurement. Results: When the first cavity fields are scaled by a factor of 0.475, the peak magnitude of the electric fields within the waveguide are calculated to be 223.1 MV/m, 29% lower than the published threshold for breakdown at this operating frequency. Maximum electron energy increased from 6.2 to 10.4 MeV, and beam current increased from 134 to 170 mA. The focal spot FWHM is decreased slightly from 0.07 to 0.05 mm, and the width of the energy spectrum increased slightly from 0.44 to 0.70 MeV. Monte Carlo results show d{sub max} is at 2.15 cm for a 10 Multiplication-Sign 10 cm{sup 2} field, compared with 2.3 cm for a Varian 10 MV linac, while the penumbral widths are 4.8 and 5.6 mm, respectively. Conclusions: The authors' simulation results show that a short, high-energy, s-band accelerator is feasible and electric breakdown is not expected to interfere with operation at these field strengths. With minor modifications to the first coupling cavity, all electron beam parameters are improved.

Baillie, Devin [Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Aubin, J. St. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Steciw, S. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

2013-04-15T23:59:59.000Z

378

Lower bound estimation for low power high-level synthesis  

Science Conference Proceedings (OSTI)

This paper addresses the problem of estimating lower bounds on the power consumption in scheduled data flow graphs with a fixed number of allocated resources prior to binding. The estimated bound takes into account the effects of resource sharing. It ...

Lars Kruse; Eike Schmidt; Gerd Jochens; Ansgar Stammermann; Wolfgang Nebel

2000-09-01T23:59:59.000Z

379

High power density supercapacitors using locally aligned carbon nanotube electrodes  

E-Print Network (OSTI)

B E 1999 Electrochemical Supercapacitor ( New York: Kluwer–power density of a supercapacitor is its most remarkablepower density of a supercapacitor is given by P max = V i

Du, C S; Yeh, J; Pan, Ning

2005-01-01T23:59:59.000Z

380

An evolutionary fuel assembly design for high power density BWRs  

E-Print Network (OSTI)

An evolutionary BWR fuel assembly design was studied as a means to increase the power density of current and future BWR cores. The new assembly concept is based on replacing four traditional assemblies and large water gap ...

Karahan, Aydin

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

The design of high power density annular fuel for LWRs  

E-Print Network (OSTI)

Fuel performance models have been developed to assess the performance of internally and externally cooled LWR annular fuel. Such fuel may be operated at 30-50% higher core power density than the current operating LWRs, and ...

Yuan, Yi, 1975-

2004-01-01T23:59:59.000Z

382

Fast thermometry for superconducting rf cavity testing  

SciTech Connect

Fast readout of strategically placed low heat capacity thermometry can provide valuable information of Superconducting RF (SRF) cavity performance. Such a system has proven very effective for the development and testing of new cavity designs. Recently, several resistance temperature detectors (RTDs) were installed in key regions of interest on a new 9 cell 3.9 GHz SRF cavity with integrated HOM design at FNAL. A data acquisition system was developed to read out these sensors with enough time and temperature resolution to measure temperature changes on the cavity due to heat generated from multipacting or quenching within power pulses. The design and performance of the fast thermometry system will be discussed along with results from tests of the 9 cell 3.9GHz SRF cavity.

Orris, Darryl; Bellantoni, Leo; Carcagno, Ruben H.; Edwards, Helen; Harms, Elvin Robert; Khabiboulline, Timergali N.; Kotelnikov, Sergey; Makulski, Andrzej; Nehring, Roger; Pischalnikov, Yuriy; /Fermilab

2007-06-01T23:59:59.000Z

383

Proposal of an Arc Detection Technique Based on RF Measurements for the ITER ICRF Antenna  

SciTech Connect

RF arc detection is a key operational and safety issue for the ICRF system on ITER. Indeed the high voltages inside the antenna put it at risk of arcing, which could cause substantial damage. This paper describes the various possibilities explored by circuit simulation and the strategy now considered to protect the ITER ICRF antenna from RF arcs.

Huygen, S.; Dumortier, P.; Durodie, F.; Messiaen, A.; Vervier, M.; Vrancken, M. [LPP/ERM-KMS, Association EURATOM-Belgian State, Brussels (Belgium); Wooldridge, E. [EURATOM/CCFE Fusion Association, Culham Science Centre (United Kingdom)

2011-12-23T23:59:59.000Z

384

OXIDATION OF DRY HYDROCARBONS AT HIGH-POWER DENSITY ANODES  

DOE Green Energy (OSTI)

This work builds upon discoveries by the University of Pennsylvania and others pertaining to the oxidation of dry hydrocarbon fuels in high temperature solid oxide fuel cells. The work reported here was restricted primarily to dry methane and confirms that YSZ-based cells, having ceria in the anode as a catalyst and copper in the anode as a current collector, can operate on dry methane for extended periods. Thirty-three lab-scale cells of various designs were fabricated and operated under a variety of conditions. The longest-lived cell gave stable performance on dry methane at 800 C for over 305 hours. Only slight carbon deposition was noted at the completion of the test. A corresponding nickel/YSZ-based anode would have lasted for less than an hour under these test conditions (which included open circuit potential measurements) before carbon fouling essentially destroyed the cell. The best performing cell achieved 112 mW/cm{sub 2} on dry methane at 800 C. Several problems were encountered with carbon fouling and declining open circuit voltages in many of the test cells after switching from operation on hydrogen to dry methane. Although not rigorously confirmed by experimentation, the results suggested that air infiltration through less than perfect perimeter seals or pinholes in the electrolytes, or both gave rise to conditions that caused the carbon fouling and OCV decline. Small amounts of air reacting with methane in a partial oxidation reaction could produce carbon monoxide that, in turn, would deposit the carbon. If this mechanism is confirmed, it implies that near perfect hardware is required for extended operation. Some evidence was also found for the formation of electrical shorts, probably from carbon deposits bridging the electrolyte. Work with odorized methane and with methane containing 100-ppm hydrogen sulfide confirmed that copper is stable at 800 C in dry hydrocarbon fuels in the presence of sulfur. In a number of cases, but not exclusively, the performance life on dry methane with sulfur compounds was much longer than with dry methane alone. The effect of sulfur compounds in these cases appeared to correlate with inhibition of carbon deposition. Mixed results were obtained for the effect of the sulfur compounds on power density. Progress also was made in understanding the mechanisms involved in direct utilization of dry natural gas. Evidence was developed for three possible mechanisms for dry methane utilization in addition to the usually cited mechanism--direct oxidation of methane by oxygen anions. Further work is required at a fundamental level before the knowledge gained here can be translated into higher levels of performance.

K.Krist; O. Spaldon-Stewart; R. Remick

2004-03-01T23:59:59.000Z

385

Generation of high peak power pulse using 2 stage erbium-doped fiber amplifier  

E-Print Network (OSTI)

This thesis presents the results obtained from generation of high repetition rate, high power output pulse using an erbium-doped fiber amplifier (EDFA). Two stage amplification was employed. The first stage setup used 980nm pump laser to pump erbium-doped fiber. For the second stage, two 1480nm pump lasers were used to pump erbium-doped fiber in both forward and backward propagating direction. The signal laser was modulated to produce pulses with high repetition rate high peak power. The first stage produced pulse peak power of 2.52W. The overall output peak power, which is produced by the first and second stage, is 16W.

Lee, Kyung-Woo

2000-01-01T23:59:59.000Z

386

Low-Cost, High-Power Laser for Analytical and Other ...  

Search PNNL. PNNL Home; About; Research; Publications; Jobs; News; Contacts; Low-Cost, High-Power Laser for Analytical and Other Applications. ...

387

A conceptual scheme for focusing of high power microwaves in SYMPLE  

Science Conference Proceedings (OSTI)

The conceptual Scheme of Focusing the High pulsed microwave power generated by "VIRCATOR" on plasma produced in "SYMPLE", using Plasma Lens, is discussed.

Renu Bahl; K. Sathyanarayna; V. P. Anitha; Priyavandna J. Rathod; Y. C. Saxena

2011-02-01T23:59:59.000Z

388

DEPOSITION OF NIOBIUM AND OTHER SUPERCONDUCTING MATERIALS WITH HIGH POWER IMPULSE MAGNETRON SPUTTERING: CONCEPT AND FIRST RESULTS  

E-Print Network (OSTI)

Workshop on RF Superconductivity, DESY, Hamburg, Germany,Gennaro, Physica C: Superconductivity 441 (2006) 130. [10]the Limits of RF Superconductivity, Padua, Italy, 2010. [12

Anders, Andre

2013-01-01T23:59:59.000Z

389

High-Temperature High-Power Packaging Techniques for HEV Traction Applications  

DOE Green Energy (OSTI)

A key issue associated with the wider adoption of hybrid-electric vehicles (HEV) and plug in hybrid-electric vehicles (PHEV) is the implementation of the power electronic systems that are required in these products. One of the primary industry goals is the reduction in the price of these vehicles relative to the cost of traditional gasoline powered vehicles. Today these systems, such as the Prius, utilize one coolant loop for the engine at approximately 100 C coolant temperatures, and a second coolant loop for the inverter at 65 C. One way in which significant cost reduction of these systems could be achieved is through the use of a single coolant loop for both the power electronics as well as the internal combustion engine (ICE). This change in coolant temperature significantly increases the junction temperatures of the devices and creates a number of challenges for both device fabrication and the assembly of these devices into inverters and converters for HEV and PHEV applications. Traditional power modules and the state-of-the-art inverters in the current HEV products, are based on chip and wire assembly and direct bond copper (DBC) on ceramic substrates. While a shift to silicon carbide (SiC) devices from silicon (Si) devices would allow the higher operating temperatures required for a single coolant loop, it also creates a number of challenges for the assembly of these devices into power inverters. While this traditional packaging technology can be extended to higher temperatures, the key issues are the substrate material and conductor stability, die bonding material, wire bonds, and bond metallurgy reliability as well as encapsulation materials that are stable at high operating temperatures. The larger temperature differential during power cycling, which would be created by higher coolant temperatures, places tremendous stress on traditional aluminum wire bonds that are used to interconnect power devices. Selection of the bond metallurgy and wire bond geometry can play a key role in mitigating this stress. An alternative solution would be to eliminate the wire bonds completely through a fundamentally different method of forming a reliable top side interconnect. Similarly, the solders used in most power modules exhibit too low of a liquidus to be viable solutions for maximum junction temperatures of 200 C. Commonly used encapsulation materials, such as silicone gels, also suffer from an inability to operate at 200 C for extended periods of time. Possible solutions to these problems exist in most cases but require changes to the traditional manufacturing process used in these modules. In addition, a number of emerging technologies such as Si nitride, flip-chip assembly methods, and the elimination of base-plates would allow reliable module development for operation of HEV and PHEV inverters at elevated junction temperatures.

Elshabini, Aicha [University of Idaho; Barlow, Fred D. [University of Idaho

2006-11-01T23:59:59.000Z

390

Detection of nanosecond-scale, high power THz pulses with a field effect transistor  

Science Conference Proceedings (OSTI)

We demonstrate detection and resolution of high power, 34 ns free electron laser pulses using a rectifying field effect transistor. The detector remains linear up to an input power of 11 {+-} 0.5 W at a pulse energy of 20 {+-} 1 {mu}J at 240 GHz. We compare its performance to a protected Schottky diode, finding a shorter intrinsic time constant. The damage threshold is estimated to be a few 100 W. The detector is, therefore, well-suited for characterizing high power THz pulses. We further demonstrate that the same detector can be used to detect low power continuous-wave THz signals with a post detection limited noise floor of 3.1 {mu}W/{radical}(Hz). Such ultrafast, high power detectors are important tools for high power and high energy THz facilities such as free electron lasers.

Preu, S. [Physics Department and Institute for Terahertz Science and Technology, University of California, Santa Barbara, California 93106 (United States); Materials Department, University of California, Santa Barbara, California 93106 (United States); Chair for Applied Physics, University of Erlangen-Nuremberg, 91058 Erlangen (Germany); Lu, H.; Gossard, A. C. [Materials Department, University of California, Santa Barbara, California 93106 (United States); Sherwin, M. S. [Physics Department and Institute for Terahertz Science and Technology, University of California, Santa Barbara, California 93106 (United States)

2012-05-15T23:59:59.000Z

391

Test results of the AGS Booster low frequency RF system  

Science Conference Proceedings (OSTI)

The Band II RF system was originally built to support the Booster operations during the acceleration of heavy ions. Designed to sweep from 0.6 to 2.5 MHz, it was build and successfully tested over a much broader range reaching 4 MHz. Voltages up to more than 20 kV were reached over the design frequency range. The system consists of two stations, each of which is made of one single gap cavity directly driven by a grounded cathode push pull power amplifier. The low Q high permeability ferrites needed in the coaxial cavity in order to reach the lower end of the band make tuning extremely easy. Both systems were thoroughly tested both at single frequencies and on a sweep and are now installed in the ring, ready for operations. Static measurements showed no high-loss effects. The Band 11 system has been fully described in a previous paper; presented here are the results of the ``bench`` tests that lead to important performance improvements.

Sanders, R.T.; Cameron, P.; Damm, R.; Dunbar, A.; Goldman, M.; Kasha, D.; McNerney, A.; Meth, M.; Ratti, A.; Spitz, R.

1993-06-01T23:59:59.000Z

392

Low jitter RF distribution system  

SciTech Connect

A timing signal distribution system includes an optical frequency stabilized laser signal amplitude modulated at an rf frequency. A transmitter box transmits a first portion of the laser signal and receive a modified optical signal, and outputs a second portion of the laser signal and a portion of the modified optical signal. A first optical fiber carries the first laser signal portion and the modified optical signal, and a second optical fiber carries the second portion of the laser signal and the returned modified optical signal. A receiver box receives the first laser signal portion, shifts the frequency of the first laser signal portion outputs the modified optical signal, and outputs an electrical signal on the basis of the laser signal. A detector at the end of the second optical fiber outputs a signal based on the modified optical signal. An optical delay sensing circuit outputs a data signal based on the detected modified optical signal. An rf phase detect and correct signal circuit outputs a signal corresponding to a phase stabilized rf signal based on the data signal and the frequency received from the receiver box.

Wilcox, Russell; Doolittle, Lawrence; Huang, Gang

2012-09-18T23:59:59.000Z

393

RF Breakdown Studies Using a 1.3 GHZ Test Cell  

DOE Green Energy (OSTI)

Many present and future particle accelerators are limited by the maximum electric gradient and peak surface fields that can be realized in RF cavities. Despite considerable effort, a comprehensive theory of RF breakdown has not been achieved and mitigation techniques to improve practical maximum accelerating gradients have had only limited success. Recent studies have shown that high gradients can be achieved quickly in 805 MHz RF cavities pressurized with dense hydrogen gas without the need for long conditioning times, because the dense gas can dramatically reduce dark currents and multipacting. In this project we use this high pressure technique to suppress effects of residual vacuum and geometry found in evacuated cavities to isolate and study the role of the metallic surfaces in RF cavity breakdown as a function of magnetic field, frequency, and surface preparation. A 1.3-GHz RF test cell with replaceable electrodes (e.g. Mo, Cu, Be, W, and Nb) and pressure barrier capable of operating both at high pressure and in vacuum has been designed and built, and preliminary testing has been completed. A series of detailed experiments is planned at the Argonne Wakefield Accelerator. At the same time, computer simulations of the RF Breakdown process will be carried out to help develop a consistent physics model of RF Breakdown. In order to study the effect of the radiofrequency on RF Breakdown, a second test cell will be designed, fabricated, and tested at a lower frequency, most likely 402.5 MHz.

Sah, R.; Johnson, R.P.; Neubauer, M.; /Muons Inc., Batavia; Conde, M.; Gai, W.; /Argonne; Moretti, A.; Popovic, M.; Yonehara, K.; /Fermilab; Byrd, J.; Li, D.; /LBL, Berkeley; BastaniNejad, M.; /Old Dominion U.

2009-05-01T23:59:59.000Z

394

RF Breakdown Studies Using a 1.3-GHz Text Cell  

DOE Green Energy (OSTI)

Many present and future particle accelerators are limited by the maximum electric gradient and peak surface fields that can be realized in RF cavities. Despite considerable effort, a comprehensive theory of RF breakdown has not been achieved and mitigation techniques to improve practical maximum accelerating gradients have had only limited success. Recent studies have shown that high gradients can be achieved quickly in 805 MHz RF cavities pressurized with dense hydrogen gas without the need for long conditioning times, because the dense gas can dramatically reduce dark currents and multipacting. In this project we use this high pressure technique to suppress effects of residual vacuum and geometry found in evacuated cavities to isolate and study the role of the metallic surfaces in RF cavity breakdown as a function of magnetic field, frequency, and surface preparation. A 1.3-GHz RF test cell with replaceable electrodes (e.g. Mo, Cu, Be, W, and Nb) and pressure barrier capable of operating both at high pressure and in vacuum has been designed and built, and preliminary testing has been completed. A series of detailed experiments is planned at the Argonne Wakefield Accelerator. At the same time, computer simulations of the RF Breakdown process will be carried out to help develop a consistent physics model of RF Breakdown. In order to study the effect of the radiofrequency on RF Breakdown, a second test cell will be designed, fabricated, and tested at a lower frequency, most likely 402.5 MHz.

Sah, R.; Johnson, R. P.; Neubauer, M.; Conde, M.; Gai, W.; Moretti, A.; Popovic, M.; Yonehara, K.; Byrd, J.; Li, D.; BastaniNejad, M.; Elmustafa, M.

2009-05-04T23:59:59.000Z

395

The upgrade project for the RF system for the Brookhaven AGS  

SciTech Connect

The AGS operates a varied program of proton, heavy ion, and polarized proton acceleration for fixed-target experiments and will soon serve as the injector of these beams into the Relativistic Heavy Ion Collider, RHIC. The new Booster synchrotron extends the range of intensities and masses that can be accelerated. The 1.5 GeV injection energy increases the space charge limit by a factor of four to more than 6 {times} 10{sup 13} protons per pulse. To accommodate the increased beam current the rf system will be upgraded to provide more power and lower impedance to the beam. The flexibility of the rf system will also be enhanced by virtue of a new rf beam control system and installation of individual tuning servos for the ten rf cavities. The fundamental necessity for upgrading the rf system is to deliver more power to the accelerating beam. Three key ingredients of the upgrade project addressing this problem is (1) new power amplifiers provide the necessary power, and are closely coupled to the cavities, (2) wideband rf feedback reduces the effective impedance by a factor of 10, and (3) the capacitors loading the acceleration gaps (four per cavity) are increased from 275 pF to 600 pF.

Brennan, J.M.; Ciardullo, D.J.; Hayes, T.; Meth, M.; McNerney, A.J.; Otis, A.; Pirkl, W.; Sanders, R.; Spitz, R.; Toldo, F.; Zaltsman, A.

1993-06-01T23:59:59.000Z

396

HIGH AVERAGE POWER UV FREE ELECTRON LASER EXPERIMENTS AT JLAB  

Science Conference Proceedings (OSTI)

Having produced 14 kW of average power at {approx}2 microns, JLAB has shifted its focus to the ultraviolet portion of the spectrum. This presentation will describe the JLab UV Demo FEL, present specifics of its driver ERL, and discuss the latest experimental results from FEL experiments and machine operations.

Douglas, David; Evtushenko, Pavel; Gubeli, Joseph; Hernandez-Garcia, Carlos; Legg, Robert; Neil, George; Powers, Thomas; Shinn, Michelle D; Tennant, Christopher

2012-07-01T23:59:59.000Z

397

FUTURE POWER GRID INITIATIVE Real-time High-Performance  

E-Print Network (OSTI)

mathematical models, next-generation simulation and analytics capabilities for the power November 2012 PNNL-SA-90011 Peter Hui Pacific Northwest National Laboratory (509) 372-6414 peter.hui@pnnl.gov ABOUT FPGI Infrastructure Operations Center (EIOC), the Pacific Northwest National Laboratory's (PNNL) national electric

398

High efficiency carbonate fuel cell/turbine hybrid power cycles  

SciTech Connect

Carbonate fuel cells developed in commercial 2.85 MW size, have an efficiency of 57.9%. Studies of higher efficiency hybrid power cycles were conducted to identify an economically competitive system and an efficiency over 65%. A hybrid power cycle was identified that includes a direct carbonate fuel cell, a gas turbine, and a steam cycle, which generates power at a LHV efficiency over 70%; it is called a Tandem Technology Cycle (TTC). In a TTC operating on natural gas fuel, 95% of the fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming the fuel, and flows to a direct carbonate fuel cell system which generates 72% of the power. The portion of fuel cell anode exhaust not recycled, is burned and heat is transferred to compressed air from a gas turbine, heating it to 1800 F. The stream is then heated to 2000 F in gas turbine burner and expands through the turbine generating 13% of the power. Half the gas turbine exhaust flows to anode exhaust burner and the rest flows to the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Studies of the TTC for 200 and 20 MW size plants quantified performance, emissions and cost-of-electricity, and compared the TTC to gas turbine combined cycles. A 200-MW TTC plant has an efficiency of 72.6%; estimated cost of electricity is 45.8 mills/kWhr. A 20-MW TTC plant has an efficiency of 65.2% and a cost of electricity of 50 mills/kWhr.

Steinfeld, G.

1996-12-31T23:59:59.000Z

399

Status and Plans for a Superconducting RF Accelerator Test Facility at Fermilab  

Science Conference Proceedings (OSTI)

The Advanced Superconducting Test Accelerator (ASTA) is being constructed at Fermilab. The existing New Muon Lab (NML) building is being converted for this facility. The accelerator will consist of an electron gun, injector, beam acceleration section consisting of 3 TTF-type or ILC-type cryomodules, multiple downstream beam lines for testing diagnostics and conducting various beam tests, and a high power beam dump. When completed, it is envisioned that this facility will initially be capable of generating a 750 MeV electron beam with ILC beam intensity. An expansion of this facility was recently completed that will provide the capability to upgrade the accelerator to a total beam energy of 1.5 GeV. Two new buildings were also constructed adjacent to the ASTA facility to house a new cryogenic plant and multiple superconducting RF (SRF) cryomodule test stands. In addition to testing accelerator components, this facility will be used to test RF power systems, instrumentation, and control systems for future SRF accelerators such as the ILC and Project-X. This paper describes the current status and overall plans for this facility.

Leibfritz, J.; Andrews, R.; Baffes, C.M.; Carlson, K.; Chase, B.; Church, M.D.; Harms, E.R.; Klebaner, A.L.; Kucera, M.; Martinez, A.; Nagaitsev, S.; /Fermilab

2012-05-01T23:59:59.000Z

400

Resonant ring for testing of accelerator RF windows  

SciTech Connect

A klystron-driven resonant ring has been designed and assembled at the Los Alamos National Laboratory for use in the Accelerator Production of Tritium Project (APT). The ring was built to test rf windows for the 700 MHz section of the APT accelerator. The ring has been designed to apply an effective power of approximately 1 MW on test windows. Details of ring design, operation and performance will be presented.

Gerken, E.; Rees, D.; Roybal, W.; Cummings, K. [Los Alamos National Lab., NM (United States); Gahl, J.M. [Univ. of New Mexico, Albuquerque, NM (United States)

1997-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Power Flow Management in a High Penetration Wind-Diesel Hybrid Power System with Short-Term Energy Storage  

Science Conference Proceedings (OSTI)

This paper is intended as an introduction to some of the control challenges faced by developers of high penetration wind-diesel systems, with a focus on the management of power flows in order to achieve precise regulation of frequency and voltage in the face of rapidly varying wind power input and load conditions. The control algorithms presented herein are being implemented in the National Renewable Energy Laboratory (NREL) high penetration wind-diesel system controller that will be installed in the village of Wales, Alaska, in early 2000.

Drouilhet, S. M.

1999-07-29T23:59:59.000Z

402

A High Power Liquid Hydrogen Target for Parity Violation Experiments  

DOE Green Energy (OSTI)

Parity-violating electron scattering measurements on hydrogen and deuterium, such as those underway at the Bates and CEBAF laboratories, require luminosities exceeding 10{sup 38} cm{sup -2} s{sup -1}, resulting in large beam power deposition into cryogenic liquid. Such targets must be able to absorb 500 watts or more with minimal change in target density. A 40 cm long liquid hydrogen target, designed to absorb 500 watts of beam power without boiling, has been developed for the SAMPLE experiment at Bates. In recent tests with 40 {micro}A of incident beam, no evidence was seen for density fluctuations in the target, at a sensitivity level of better than 1%. A summary of the target design and operational experience will be presented.

Mark, John W.

2003-06-06T23:59:59.000Z

403

Guidelines and Specifications for High-Reliability Fossil Power Plants  

Science Conference Proceedings (OSTI)

The steel alloy known as Grade 91 has achieved broad acceptance within the modern power industry for use in fabricating a variety of critical pressure part components, including tubing, piping, and headers. As is true for all of the creep-strength-enhanced ferritic (CSEF) steels, designers favor Grade 91 because, within a specific temperature range and when properly processed, it provides superior elevated temperature strength at substantially lower cost than the austenitic stainless steels, while mainta...

2011-11-09T23:59:59.000Z

404

High Power Modulator/regulators for neutral beam sources  

SciTech Connect

PPPL has recently completed two new Modulator/Regulators for neutral injection sources used on the ATC machine and is constructing four new ones for use with sources on the PLT machine. The ATC modulator uses the well proven 4CX35,000C tetrode as the main switch tube, while the PLT modulators will be using the new but significantly higher powered X-2170 tetrodes. Some interesting circuit and manufacturing techniques are discussed. (MOW)

Lawson, J.Q.; Deitz, A.

1975-01-01T23:59:59.000Z

405

A non-intrusive beam power monitor for high power pulsed or continuous wave lasers  

DOE Patents (OSTI)

A system and method for monitoring the output of a laser is provided in which the output of a photodiode disposed in the cavity of the laser is used to provide a correlated indication of the laser power. The photodiode is disposed out of the laser beam to view the extraneous light generated in the laser cavity whose intensity has been found to be a direct correlation of the laser beam output power level. Further, the system provides means for monitoring the phase of the laser output beam relative to a modulated control signal through the photodiode monitor.

Hawsey, R.A.; Scudiere, M.B.

1991-05-29T23:59:59.000Z

406

A non-intrusive beam power monitor for high power pulsed or continuous wave lasers  

DOE Patents (OSTI)

A system for monitoring the output of a laser is provided in which the output of a photodiode disposed in the cavity of the laser is used to provide a correlated indication of the laser power. The photodiode is disposed out of the laser beam to view the extraneous light generated in the laser cavity whose intensity has been found to be a direct correlation of the laser beam output power level. Further, the system provides means for monitoring the phase of the laser output beam relative to a modulated control signal through the photodiode monitor. 4 figs.

Hawsey, R.A.; Scudiere, M.B.

1989-09-26T23:59:59.000Z

407

DESY, February 2001, TESLA Report 2001-04 Concept of the High Power e  

E-Print Network (OSTI)

DESY, February 2001, TESLA Report 2001-04 Concept of the High Power e± Beam Dumps for TESLA W. Bialowons, M. Maslov, M. Schmitz, V. Sytchev #12;1 Concept of the High Power e± Beam Dumps for TESLA W............................................................................................................... 19 #12;2 1 Introduction The TESLA accelerator is equipped with quite a number of extraction lines

408

A high-voltage low-power DC-DC buck regulator for automotive applications  

Science Conference Proceedings (OSTI)

This work presents a High-Voltage Low-Power CMOS DC-DC buck regulator for automotive applications. The overall system, including the high and low voltage analog devices, the power MOS and the low voltage digital devices, was realized in the Austriamicrosystems ... Keywords: DC-DC regulator, buck converter, current control, low quiscent current, pulse frequency modulation

G. Pasetti; L. Fanucci; R. Serventi

2010-03-01T23:59:59.000Z

409

High power light emitting diode based setup for photobleaching fluorescent impurities  

E-Print Network (OSTI)

High power light emitting diode based setup for photobleaching fluorescent impurities Tobias K be photobleached before final sample preparation. The instrument consists of high power light emitting diodes for simple photobleaching pur- poses, we designed a simple but efficient lighting system using light emitting

Kaufman, Laura

410

Single electron beam rf feedback free electron laser  

DOE Patents (OSTI)

A free electron laser system and electron beam system for a free electron laser which uses rf feedback to enhance efficiency are described. Rf energy is extracted from a single electron beam by decelerating cavities and energy is returned to accelerating cavities using rf returns, such as rf waveguides, rf feedthroughs, resonant feedthroughs, etc. This rf energy is added to rf klystron energy to reduce the required input energy and thereby enhance energy efficiency of the system.

Brau, C.A.; Stein, W.E.; Rockwood, S.D.

1981-02-11T23:59:59.000Z

411

High-power electron Landau-heating experiments in the lower hybrid frequency range in a tokamak plasma  

DOE Green Energy (OSTI)

The effectiveness of plasma heating by electron Landau interaction in the lower hybrid range of frequencies in tokamak plasmas is demonstrated. Upon injection of 850 kW of rf power at a density of n-barsubeapprox. =1.4 x 10sup14 cmsup-3, an electron temperature increase of 1.0 keV and an ion temperature increase of 0.8 keV was achieved. These results are compared with transport and ray-tracing code predictions.

Porkolab, M.; Lloyd, B.; Takase, Y.; Bonoli, P.; Fiore, C.; Gandy, R.; Granetz, R.; Griffin, D.; Gwinn, D.; Lipscultz, B.

1984-09-24T23:59:59.000Z

412

Analysis of Power Quality Concerns at a County High School  

Science Conference Proceedings (OSTI)

This case study describes the findings from the site survey at a county high school and outlines recommended procedures for dealing with the new computer loads.

2003-12-31T23:59:59.000Z

413

Lower power prices and high repair costs drive nuclear retirements ...  

U.S. Energy Information Administration (EIA)

However, concerns over the length of the review process and the high costs associated with steam generator repairs led SCE to retire both reactors.

414

Microsoft PowerPoint - High Temperature Thermoelectric_Ohuchi  

NLE Websites -- All DOE Office Websites (Extended Search)

High T Seebeck tester *Nano-Micro Composites * Reduction in grain size adversely affects electron mobility * Research into nano-micro composites to scatter phonons and preserve...

415

BPA curtails wind power generators during high hydropower ...  

U.S. Energy Information Administration (EIA)

Energy Information Administration - EIA ... The hydro capacity in the Pacific Northwest generates large amounts of electricity when river flows are high, ...

416

Overview of the RF Systems for LCLS  

SciTech Connect

The Linac Coherent Light Source (LCLS) at SLAC, when it becomes operational in 2009, will provide its user community with an X-ray source many orders of magnitude brighter than anything available in the world at that time [1]. The electron beam acceleration will be provided by existing and new RF systems capable of maintaining the amplitude and phase stability of each bunch to extremely tight tolerances. RF feedback control of the various RF systems will be fundamental in ensuring the beam arrives at the LCLS undulator at precisely the required energy and peak current phase. This paper details the requirements for RF stability for the various LCLS RF systems and also highlights proposals for how these injector and Linac RF systems can meet these tight constraints.

McIntosh, P.; Akre, R.; Boyce, R.; Emma, P.; Hill, A.; Rago, C.; /SLAC

2005-06-15T23:59:59.000Z

417

Overview of the RF Systems for LCLS  

E-Print Network (OSTI)

The Linac Coherent Light Source (LCLS) at SLAC, when it becomes operational in 2009, will provide its user community with an X-ray source many orders of magnitude brighter than anything available in the world at that time. The electron beam acceleration will be provided by existing and new RF systems capable of maintaining the amplitude and phase stability of each bunch to extremely tight tolerances. RF feedback control of the various RF systems will be fundamental in ensuring the beam arrives at the LCLS undulator at precisely the required energy and phase. This paper details the requirements for RF stability for the various LCLS RF systems and also highlights proposals for how these injector and Linac RF systems can meet these constraints.

McIntosh, Peter; Boyce, Richard; Emma, Paul; Hill, Alan; Rago, Carl

2005-01-01T23:59:59.000Z

418

Develop high energy high power Li-ion battery cathode materials : a first principles computational study  

E-Print Network (OSTI)

electric vehicle (PEV), performance requirements are raised especially from the aspects of energy/power density, cycling life and safety

Xu, Bo; Xu, Bo

2012-01-01T23:59:59.000Z

419

Visual observation of boiling in high power liquid target  

Science Conference Proceedings (OSTI)

A top pressurized, batch style, 3.15 mL total volume (2.5 mL fill volume) water target with transparent viewing windows was operated on an IBA 18/9 cyclotron at 18 MeV proton energy and beam power up to 1.1 kW. Video recordings documented bubble formation and transport, and blue light from de-excitation of water molecules produced images of proton beam stopping geometry including location of the Bragg peak.

Peeples, J. L.; Stokely, M. H.; Poorman, M. C.; Magerl, M.; Wieland, B. W. [Bruce Technologies Inc., 1939 Evans Rd. Cary, NC 27513 (United States); IBA Molecular, 801 Forestwood Dr. Romeoville, IL 60446 (United States); Bruce Technologies Inc., 1939 Evans Rd. Cary, NC 27513 (United States)

2012-12-19T23:59:59.000Z

420

Development of High Average Power Lasers for the Photon Collider  

SciTech Connect

The laser and optics system for the photon collider seeks to minimize the required laser power by using an optical stacking cavity to recirculate the laser light. An enhancement of between 300 to 400 is desired. In order to achieve this the laser pulses which drive the cavity must precisely match the phase of the pulse circulating within the cavity. We report on simulations of the performance of a stacking cavity to various variations of the drive laser in order to specify the required tolerances of the laser system.

Gronberg, Jeff; /LLNL, Livermore; Stuart, Brent; /LLNL, Livermore; Seryi, Andrei; /SLAC

2012-07-05T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Swept measurement of high power I-V curves  

SciTech Connect

Performance evaluation of photovoltaic (PV) arrays under a variety of conditions provides important information for the design and maintenance of PV systems. One of the principal methods for assessing an array's performance is to plot its current, I, versus voltage, V, curve. Following a brief review of techniques for measuring the I-V curve, a new capacitive-based approach is presented. It uses a rapid sweep of the I-V curve which substantially reduces the average power transfer between array and load, and in turn, substantially reduces the size and weight of the curve tracer. Both theoretical and practical aspects of the approach are presented for a 10-kW unit. Performance is verified by comparison with I-V curves obtained by using a conventional load. The agreement is found to be excellent. Approximately an order of magnitude reduction in size, weight and power consumption over conventional units was realized with the experimental I-V curve tracer.

Cox, C.H.; Warner, T.H.

1982-09-01T23:59:59.000Z

422

Swept measurement of high-power I-V curves  

SciTech Connect

Performance evaluation of photovoltaic (PV) arrays under a variety of conditions provides important information for the design and maintenance of PV systems. One of the principal methods for assessing an arrays's performance is to plot its current, I, versus voltage, V, curve. Following a brief review of techniques for measuring the I-V curve, a new capacitive-based approach is presented. It uses a rapid sweep of the I-V curve which substantially reduces the average power transfer between array and load, and in turn, substantially reduces the size and weight of the curve tracer. Both theoretical and practical aspects of the approach are presented for a 10-kW unit. Performance is verified by comparison with I-V curves obtained by using a conventional load. The agreement is found to be excellent. Approximately an order of magnitude reduction in size, weight and power consumption over conventional units was realized with the experimental I-V curve tracer.

Cox, C.H. III; Warner, T.H.

1982-01-01T23:59:59.000Z

423

Micropower RF transponder with superregenerative receiver and RF receiver with sampling mixer  

DOE Patents (OSTI)

A micropower RF transponder employs a novel adaptation of the superregenerative receiver wherein the quench oscillator is external to the regenerative transistor. The quench oscillator applies an exponentially decaying waveform rather than the usual sinewave to achieve high sensitivity at microampere current levels. Further improvements include circuit simplifications for antenna coupling, extraction of the detected signal, and a low-voltage bias configuration that allows operation with less than a 1-volt rail voltage. The inventive transponder is expected to operate as long as the battery shelf life. 13 figs.

McEwan, T.E.

1997-05-13T23:59:59.000Z

424

Micropower RF transponder with superregenerative receiver and RF receiver with sampling mixer  

DOE Patents (OSTI)

A micropower RF transdponder employs a novel adaptation of the superregenerative receiver wherein the quench oscillator is external to the regenerative transistor. The quench oscillator applies an exponentially decaying waveform rather than the usual sinewave to achieve high sensitivity at microampere current levels. Further improvements include circuit simplifications for antenna coupling, extraction of the detected signal, and a low-voltage bias configuration that allows operation with less than a 1-volt rail voltage. The inventive transponder is expected to operate as long as the battery shelf life.

McEwan, Thomas E. (Livermore, CA)

1997-01-01T23:59:59.000Z

425

A Survey of the Urban RF Environment  

Science Conference Proceedings (OSTI)

The prevalence of sources of radio-frequency (RF) electromagnetic fields is expanding at a rapid pace.  As new wireless technologies are deployed (e.g., smart meters), questions are often raised as to what extent people are exposed to their RF emissions, and what if any effects on health and safety the RF could possibly cause. To obtain a frame of reference for the contributions of new sources to our environment, this study was designed to quantify the levels of RF fields that already exist in ...

2012-12-31T23:59:59.000Z

426

Characteristics of multiantenna rf ion source  

Science Conference Proceedings (OSTI)

We have developed a new multiantenna rf ion source for neutral beam injection and studied the effects of different antennas connected in parallel

T. Shoji; Y. Oka; NBI Group

2006-01-01T23:59:59.000Z

427

Passive RF Components - Microsystems Science, Technology, and...  

NLE Websites -- All DOE Office Websites (Extended Search)

Passive RF Components Microsystems Home Custom Microsystems Solutions Microsystems R&D Services Capabilities and Technologies Facilities Trusted Microsystems General Info About Us...

428

Measurement and modeling of mirror distortion in a high power FEL  

Science Conference Proceedings (OSTI)

Mirror heating in a high power FEL can alter the optical mode and affect the gain of the laser. This can lead to a large reduction of the laser power from ideal values. Measurements of the power and mode size in the Jefferson Lab IR Demo laser have shown clear evidence of mirror distortion at high average power leading (up to 17 kW incident on the mirrors and over 40 W absorbed per mirror). The measurements and comparisons with modeling will be presented. Both steady state and transient analyses and measurements are considered.

Benson, S.; Neil, G.; Michelle D. Shinn

2000-01-01T23:59:59.000Z

429

High-Energy, Low-Frequency Risk to the North American Bulk Power System  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

High-Energy, Low-Frequency Risk to the North American Bulk Power High-Energy, Low-Frequency Risk to the North American Bulk Power System (June 2010) High-Energy, Low-Frequency Risk to the North American Bulk Power System (June 2010) A Jointly-Commissioned Summary Report of the North American Electric Reliability Corporation and the U.S. Department of Energy's November 2009 Workshop. The North American Electric Reliability Corporation (NERC) and the U.S. Department of Energy (DOE) partnered in July of 2009 on an effort to address High-Impact, Low-Frequency risks to the North American bulk power system. In August, NERC formed a steering committee made up of industry and risk experts to lead the development of an initial workshop on the subject, chaired by Scott Moore, VP Transmission System & Region Operations for American Electric Power, and Robert Stephan, Former Assistant Secretary for

430

Application of High Power DC Arc Plasma for  

Science Conference Proceedings (OSTI)

Recent results in the R&D of thin diamond film coated WC-Co drills and end ... of High Quality Freestanding Diamond Films and Diamond Film Coated Cutting ...

431

AN ASSESSMENT OF FLYWHEEL HIGH POWER ENERGY STORAGE TECHNOLOGY FOR HYBRID VEHICLES  

Science Conference Proceedings (OSTI)

An assessment has been conducted for the DOE Vehicle Technologies Program to determine the state of the art of advanced flywheel high power energy storage systems to meet hybrid vehicle needs for high power energy storage and energy/power management. Flywheel systems can be implemented with either an electrical or a mechanical powertrain. The assessment elaborates upon flywheel rotor design issues of stress, materials and aspect ratio. Twelve organizations that produce flywheel systems submitted specifications for flywheel energy storage systems to meet minimum energy and power requirements for both light-duty and heavy-duty hybrid applications of interest to DOE. The most extensive experience operating flywheel high power energy storage systems in heavy-duty and light-duty hybrid vehicles is in Europe. Recent advances in Europe in a number of vehicle racing venues and also in road car advanced evaluations are discussed. As a frame of reference, nominal weight and specific power for non-energy storage components of Toyota hybrid electric vehicles are summarized. The most effective utilization of flywheels is in providing high power while providing just enough energy storage to accomplish the power assist mission effectively. Flywheels are shown to meet or exceed the USABC power related goals (discharge power, regenerative power, specific power, power density, weight and volume) for HEV and EV batteries and ultracapacitors. The greatest technical challenge facing the developer of vehicular flywheel systems remains the issue of safety and containment. Flywheel safety issues must be addressed during the design and testing phases to ensure that production flywheel systems can be operated with adequately low risk.

Hansen, James Gerald [ORNL

2012-02-01T23:59:59.000Z

432

High Efficiency Solar Power via Separated Photo and Voltaic Pathways  

DOE Green Energy (OSTI)

This project demonstrates a novel nanostructured solar cell architecture capable of achieving high efficiency levels that is relatively simple and inexpensive to manufacture. The high efficiency will be achieved by the novel structure that separates the path of the photons from the path of the generated charge carriers. In this way, the photon path can be long for maximum light absorption, while the path for carriers can be short for maximum electronic energy harvesting. The combination of maximum light absorption coupled with maximum carrier harvesting is the basis for the expected high efficiency. The project will develop high efficiency solar cell prototypes utilizing this unique nanostructured architecture. The project addresses the fundamental limitation inherent in all current solar cell designs, and which opens a pathway to development for high efficiency solar cells at low cost. Realizing this goal will result in a levelized cost of electricity in the range of 10¢/kWh, which would achieve the long-sought goal of making photovoltaic electricity cost competitive with fossil-fuel generated electricity without any governmental subsidies. This breakthrough would spur the already rapid growth in the photovoltaic industry to an explosive pace, with significant, widespread benefit to the national economy and the nation’s energy security. The initial target of the program is to develop single-junction solar cells using ultrathin amorphous silicon with the performance approaching that of single crystal silicon cells.

Michael J. Naughton

2009-02-17T23:59:59.000Z

433

Design, simulation and conditioning of the fundamental power couplers for BNL SRF gun  

SciTech Connect

The 704 MHz SRF gun for the BNL Energy Recovery Linac (ERL) prototype uses two fundamental power couplers (FPCs) to deliver up to 1 MW of CW RF power to the half-cell cavity. To prepare the couplers for high-power RF service and process multipacting, the FPCs should be conditioned prior to installation into the gun cryomodule. A room-temperature test stand was configured for conditioning FPCs in full reflection regime with varied phase of the reflecting wave. The FPCs have been conditioned up to 250 kW in pulse mode and 125 kW in CW mode. The multipacting simulations were carried out with Track3P code developed at SLAC. The simulations matched the experimental results very well. This paper presents the FPC RF and thermal design, multipacting simulations and conditioning of the BNL gun FPCs.

Xu W.; Altinbas, Z.; Belomestnykh, S.; Ben-Zvi, I. et al

2012-05-20T23:59:59.000Z

434

High power pulsed plasma MHD experiments. Annual report 1 Jan 81-30 Sep 82  

SciTech Connect

Results of high power pulsed plasma MHD experiments are reported. An explosively driven plasma source is used to drive a Faraday mode MHD generator with an externally applied B-field of several tesla. The highest power achieved was 6 gigawatts in a 140 kJ electrical pulse delivered to a resistive load. The experimentally observed scaling relationships of power with applied B-field and electrode area are also presented.

Baum, D.W.; Gill, S.P.; Shimmin, W.L.; Watson, J.D.

1982-09-30T23:59:59.000Z

435

Nano-structured anode material for high-power battery system in electric vehicles.  

SciTech Connect

A new MSNP-LTO anode is developed to enable a high-power battery system that provides three times more power than any existing battery system. It shows excellent cycle life and low-temperature performance, and exhibits unmatched safety characteristics.

Amine, K.; Belharouak, I.; Chen, Z.; Taison, T.; Yumoto, H.; Ota, N.; Myung, S.-T.; Sun, Y.-K. (Chemical Sciences and Engineering Division); (Enerdel Lithium Power Systems); (Iwate Univ.); (Hanyang Univ.)

2010-07-27T23:59:59.000Z

436

Synthesis of hybrid nanowire arrays and their application as high power supercapacitor electrodesw  

E-Print Network (OSTI)

Synthesis of hybrid nanowire arrays and their application as high power supercapacitor electrodesw- plies.2­7 For such applications, it is extremely important to develop supercapacitors with higher power and they have been used as electrodes for supercapacitors.11­14 In spite of having ideal properties, CNT based

Ajayan, Pulickel M.

437

Electrical characterization and modelling of round spiral supercapacitors for high power applications  

E-Print Network (OSTI)

Electrical characterization and modelling of round spiral supercapacitors for high power of supercapacitors under railway and electrical traction constraints. Electrical model parameters according of supercapacitors and give precious information on its state of health. These kinds of studies need a powerful

Paris-Sud XI, Université de

438

Sunpentown: ENERGY STAR Referral (RF-330SS) | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

ENERGY STAR Referral (RF-330SS) Sunpentown: ENERGY STAR Referral (RF-330SS) May 10, 2013 DOE referred the matter of Sunpentown-brand refrigerator, model RF-330SS, manufactured by...

439

Samsung: ENERGY STAR Referral (RF26VAB) | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Samsung: ENERGY STAR Referral (RF26VAB) Samsung: ENERGY STAR Referral (RF26VAB) March 16, 2010 DOE referred the matter of Samsung refrigerator-freezer model RF26VAB to the U.S....

440

Analysis of system wide distortion in an integrated power system utilizing a high voltage DC bus and silicon carbide power devices  

E-Print Network (OSTI)

This research investigates the distortion on the electrical distribution system for a high voltage DC Integrated Power System (IPS). The analysis was concentrated on the power supplied to a propulsion motor driven by an ...

Fallier, William F. (William Frederick)

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high power rf" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Development of fluorides for high power laser optics  

Science Conference Proceedings (OSTI)

The laser-assisted thermonuclear fusion program has significant needs for improved optical materials with high transmission in the ultraviolet, and with low values of nonlinear index of refraction. Lithium fluoride (LiF) possesses a combination of optical properties which are of potential use. Single-crystalline LiF is limited by low mechanical strength. In this program, we investigated the technique of press-forging to increase the mechanical strength. LiF single crystals were press-forged over the temperature range 300 to 600/sup 0/C to produce fine-grained polycrystalline material.

Ready, J.F.; Vora, H.

1980-07-01T23:59:59.000Z

442

Impact of High Wind Power Penetration on Hydroelectric Unit Operations  

SciTech Connect

The Western Wind and Solar Integration Study (WWSIS) investigated the operational impacts of very high levels of variable generation penetration rates (up to 35% by energy) in the western United States. This work examines the impact of this large amount of wind penetration on hydroelectric unit operations. Changes in hydroelectric unit operating unit patterns are examined for an aggregation of all hydro generators. The cost impacts of maintaining hydro unit flexibility are assessed and compared for a number of different modes of system operation.

Hodge, B. M.; Lew, D.; Milligan, M.

2011-01-01T23:59:59.000Z

443

R&D ERL: Low level RF  

SciTech Connect

A superconducting RF (SRF) Energy Recovery Linac (ERL) is currently under development at the Collider-Accelerator Department (C-AD) at Brookhaven National Laboratory (BNL). The major components from an RF perspective are (a) a 5-cell SRF ERL cavity, (b) an SRF photocathode electron gun, and (c) a drive laser for the photocathode gun. Each of these RF subsystems has its own set of RF performance requirements, as well as common requirements for ensuring correct synchronism between them. A low level RF (LLRF) control system is currently under development, which seeks to leverage both technology and experience gained from the recently commissioned RHIC LLRF system upgrade. This note will review the LLRF system requirements and describe the system to be installed at the ERL.

Smith, K.

2010-01-15T23:59:59.000Z

444

High Temperature Dynamic Hohlraums on the Pulsed Power Driver Z  

SciTech Connect

In the concept of the dynamic hohlraum an imploding z-pinch is optically thick to its own radiation. Radiation may be trapped inside the pinch to give a radiation temperature inside the pinch greater than that outside the pinch. The radiation is typically produced by colliding an outer Z-pinch liner onto an inner liner. The collision generates a strongly radiating shock, and the radiation is trapped by the outer liner. As the implosion continues after the collision the radiation temperature may continue to increase due to ongoing PdV (pressure times change in volume) work done by the implosion. In principal the radiation temperature may increase to the point at which the outer liner burns through, becomes optically thin, and no longer traps the radiation. One application of the dynamic hohlraum is to drive an ICF (inertial confinement fusion) pellet with the trapped radiation field. Members of the dynamic hohlraum team at Sandia National Labs have used the pulsed power driver Z (20 LMA, 100 ns) to create a dynamic hohlraum with temperature linearly ramping from 100 to 180 eV over 5 ns. On this shot zp214 a nested tungsten wire array of 4 and 2 cm diameters with masses of 2 and 1 mg imploded onto a 2.5 mg plastic annulus at 5 mm diameter. The current return can on this shot was slotted. It is likely the radiation temperature may be increased to over 200 CV by stabilizing the pinch with a solid current return can. A current return can with 9 slots imprints 9 filaments onto the imploding pinch. This degrades the optical trapping and the quality of the liner collision. A 1.6 mm diameter capsule situated inside this dynamic hohlraum of zp214 would see 15 kJ of radiation impinging on its surface before the pinch itself collapses to a 1.6 mm diameter. Dynamic hohlraum shots including pellets are scheduled to take place on Z in September of 1998.

Armijo, J.; Chandler, G.A.; Cooper, G.; Derzon, M.S.; Fehl, D.; Gilliland, T.; Hawn, R.; Hebron, D.; Hurst, M.; Jobe, D.; Lash, J.; Lazier, S.; Leeper, R.; McGurn, J.; McKenney, J.; Mock, R.; Nash, T.J.; Nielsen, D.; Ruiz, C.; Ryan, P.; Seaman, J.F.; Torres, J.

1999-01-04T23:59:59.000Z

445

Development and Analysis of Advanced High-Temperature Technology for Nuclear Heat Transport and Power Conversion  

DOE Green Energy (OSTI)

This project by the Thermal Hydraulics Research Laboratory at U.C. Berkeley Studied advanced high-temperature heat transport and power conversion technology, in support of the Nuclear Hydrogen Initiative and Generation IV.

Per F. Peterson

2010-03-01T23:59:59.000Z

446

NEUTRONIC AND THERMAL HYDRAULIC DESIGNS OF ANNULAR FUEL FOR HIGH POWER DENSITY BWRS  

E-Print Network (OSTI)

As a promising new fuel for high power density light water reactors, the feasibility of using annular fuel for BWR services is explored from both thermal hydraulic and neutronic points of view. Keeping the bundle size ...

Morra, P.

447

Generation of high power single-cycle and multiple-cycle terahertz pulses  

E-Print Network (OSTI)

In this thesis, we present experimental methods and results of tabletop generation of high power single-cycle and frequency-tunable multiple-cycle terahertz (THz) pulses pumped with near-infrared ultrashort optical pulses ...

Chen, Zhao, S.M. Massachusetts Institute of Technology. Department of Chemistry

2013-01-01T23:59:59.000Z

448

High efficiency resonant dc/dc converter for solar power applications  

E-Print Network (OSTI)

This thesis presents a new topology for a high efficiency dc/dc resonant power converter that utilizes a resistance compression network to provide simultaneous zero voltage switching and near zero current switching across ...

Inam, Wardah

2013-01-01T23:59:59.000Z

449

Bright High Average Power Table-top Soft X-Ray Lasers  

Science Conference Proceedings (OSTI)

We have demonstrated the generation of bright soft x-ray laser pulses with record-high average power from compact plasma amplifiers excited by ultrafast solid state lasers. These lasers have numerous applications in nanoscience and nanotechnology.

Rocca, Jorge [Colorado State University, Fort Collins; Reagan, Brendon [Colorado State University, Fort Collins; Wernsing, Keith [Colorado State University, Fort Collins; Luther, Brad [Colorado State University, Fort Collins; Curtis, Alden [Colorado State University, Fort Collins; Nichols,, Anthony [Colorado State University, Fort Collins; Wang, Yong [Colorado State University, Fort Collins; Alessi, David [Colorado State University, Fort Collins; Martz, Dale [Colorado State University, Fort Collins; Yin, Liang [Colorado State University, Fort Collins; Wang, Shoujun [Colorado State University, Fort Collins; Berrill, Mark A [ORNL; Furch, Federico [Colorado State University, Fort Collins; Woolston, Mark [Colorado State University, Fort Collins; Patel, Dinesh [Colorado State University, Fort Collins; Marconi, Mario [Colorado State University, Fort Collins; Menoni, Carmen [Colorado State University, Fort Collins

2012-01-01T23:59:59.000Z