Thermal instability of electrolytic capacitor bank used for gas puff valve
It is shown that self-heating of electrolytic capacitors causes the output current of a capacitor bank to increase with successive shots even though the charge voltage is held constant. Self heating of only 10 °C can cause a near tripling in the gas output of the gas puffing valves commonly used in spheromak research. By using metallized polypropylene film capacitors instead of electrolytic capacitors the reproducibility is substantially improved (the shot-to-shot variation in gas output is reduced to be <0.5%).
© 2002 American Institute of Physics. (Received 12 March 2002; accepted for publication 15 April 2002) The author thanks F.C. Cosso and D.D. Felt for their assistance in constructing the various versions of the capacitor bank. This work was supported by U.S. DOE Grant No. DE-FG03-98ER54461.
Published - BELrsi02.pdf