A high-voltage modulator for high-power RF source research

Journal Article · Mon Apr 01 00:00:00 EST 1991 · IEEE Transactions on Electron Devices (Institute of Electrical and Electronics Engineers); (United States)

DOI:https://doi.org/10.1109/16.75211· OSTI ID:5976071

Mulligan, W J; Chen, S C; Bekefi, G; Danly, B G; Temkin, R J ^[1]

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1. Plasma Fusion Center, Massachusetts Inst. of Technology, Cambridge, MA (US)

This paper presents the design, construction, and operating results of a high-voltage modulator system capable of generating 700-kV, 2.5-{mu}s pulses at 5 pps into a load of 900 {Omega}. The modulator is used to energize a variety of high-power microwave devices requiring voltage stability and reproducibility. Voltage ripple is less than 0.2% during the 1.0-{mu}s flat top, with a shot-to-shot voltage variation of less than 0.1%. The primary circuit consists of two seven-stage tunable Rayleigh- type pulse-forming networks (PFN's) connected in parallel with a total impedance of 2.25 {Omega}, a total capacitance of 0.56 {mu}F, and a total inductance of 2.8 {mu}H. The PFN is charged by a highly stable 80-kV capacitor charging power supply (0.1% rms voltage ripple) at a rate of 10 kJ/s. The total energy stored (1.5 kJ) is released through an ITT F-187 thyratron into a 20:1 pulse transformer, which generates 700- kV, 2.5-1 {mu}s pulses. By changing the transformer, we have also obtained 250-kV, 1.7-kA pulses for driving low-impedance relativistic magnetron diodes. The flat-top voltage generated by the modulator is highly desirable for driving RF sources requiring high quality electron beams, such as free-electron lasers (FEL) and cyclotron auto-resonance masers (CARM). The modulator performance in our relativistic magnetron and CARM experiments is described.

• OSTI ID: 5976071
• Journal Information: IEEE Transactions on Electron Devices (Institute of Electrical and Electronics Engineers); (United States), Vol. 38:4; ISSN 0018-9383
• Country of Publication: United States
• Language: English

Related Subjects

24 POWER TRANSMISSION AND DISTRIBUTION
42 ENGINEERING
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
Ta
ELECTRON BEAMS
BEAM PRODUCTION
HIGH-VOLTAGE PULSE GENERATORS
RESEARCH PROGRAMS
MICROWAVE POWER TRANSMISSION
CYCLOTRON RESONANCE
ELECTRON SOURCES
FREE ELECTRON LASERS
MAGNETRONS
MASERS
MODULAR STRUCTURES
THYRATRONS
TRANSFORMERS
AMPLIFIERS
BEAMS
ELECTRICAL EQUIPMENT
ELECTRON TUBES
ELECTRONIC EQUIPMENT
EQUIPMENT
FUNCTION GENERATORS
GAS DISCHARGE TUBES
LASERS
LEPTON BEAMS
MICROWAVE AMPLIFIERS
MICROWAVE EQUIPMENT
MICROWAVE TUBES
PARTICLE BEAMS
PARTICLE SOURCES
POWER TRANSMISSION
PULSE GENERATORS
RADIATION SOURCES
RESONANCE
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426002 - Engineering- Lasers & Masers- (1990-)
661220 - Particle Beam Production & Handling
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