Effect of grid design on Cs-Ba tacitron operation and its application to space nuclear power systems

Journal Article · Fri Jan 20 04:00:00 EST 1995 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.47217· OSTI ID:166030

Wernsman, B; El-Genk, M S ^[1]

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1. Institute for Space and Nuclear Power Studies, Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

A study of the modulation capabilities of the Cs-Ba tacitron with different grid designs was made. Results showed the ignition grid potential to be independent of grid design at a modulation frequency, f{sub g}, of 1 kHz. At f{sub g} =22 kHz, discharge ignition with a 26% transparent grid was harder to achieve than at f{sub g}=1 kHz. The grid design greatly affects not only the extinguishing potential, but also the forward voltage drop. Increasing the grid transparency and/or aperture size makes it harder to extinguish the discharge (increases {vert_bar} V{sub g}{sup {minus}} {vert_bar}), but lowers the forward voltage drop across the tacitron. Increasing f{sub g} also increases {vert_bar} V{sub g}{sup {minus}} {vert_bar}, but lowers the forward voltage drop across the tacitron. Increasing f{sub g} also increases {vert_bar} V{sub g}{sup {minus}} {vert_bar} and lowers the range of Cs pressure for stable current modulation. For a TOPAZ-II type space nuclear reactor power system (SNPS), the lowest electrical power consumption by Cs-Ba tacitrons inverters, employing 34% transparent, 0.5 mm diameter holed grid and operating at I{sub C}=10 A or 20 A and f{sub g}=1 kHz, is {similar_to}6.5% of the total system output power. This electrical power consumption includes that of the grid power supply and the power loss in the tacitron during discharge. {copyright} 1995 {ital American} {ital Institute} {ital of} {ital Physics}

• Sponsoring Organization: USDOE
• OSTI ID: 166030
• Report Number(s): CONF-950110--
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 324; ISSN 0094-243X; ISSN APCPCS
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
BARIUM
CESIUM
DESIGN
ELECTRIC DISCHARGES
ELECTRIC POTENTIAL
FREQUENCY MODULATION
GRIDS
INVERTERS
OPERATION
POWER CONDITIONING CIRCUITS
POWER LOSSES
REACTORS
THERMIONIC FUEL ELEMENTS
VAPOR PRESSURE