Title :
Experimental tests of vacuum closing and opening switches for a current-multiplier (Meatgrinder) circuit
Author :
Weber, B.V. ; Boller, J.R. ; Commisso, R.J. ; Cooperstein, G. ; Moosman, B. ; Stephanakis, S.J. ; Peter, W. ; Zucker, O.
Author_Institution :
Div. of Plasma Phys., Naval Res. Lab., Washington, DC, USA
Abstract :
Summary form only given, as follows. The meatgrinder is a current-amplification circuit developed by O. Zucker that utilizes closing and opening switches and coupled inductors. A scheme was devised to implement this circuit on the Hawk generator (700 kA, 1 /spl mu/s quarter period) using POS opening switches and vacuum flashover surfaces as the closing switches. If successful, this circuit will result in an overall current gain of 1.3-1.4 on Hawk, and could therefore roughly double the energy coupled to an imploding PRS load. This initial experiment tested the switches using a simplified circuit. The required switching was demonstrated at a reduced current level (250 kA) on Hawk. Scaling the operation of the switches to higher current requires further work. The inside-out flashboard POS works best when current flow is from outside to inside, requiring positive polarity Marx charge. A posthole convolute also works best in positive polarity to eliminate premature surface flashover resulting from electron emission. The POS must open first, prior to the closing switches, or else it does not open. This is not the optimum switching sequence for the meatgrinder and results in a small efficiency penalty. The POS plasma and UV radiation must be isolated from the flashover switches using distance and baffles. This approach should be capable of operating at higher current on Hawk. An experiment could then be designed to demonstrate current gain. If successful, this technique could be considered as a way to drive a PRS load and to couple to higher power generators, such as Decade Quad.
Keywords :
flashover; plasma switches; power amplifiers; switching circuits; 1 mus; 250 kA; 4 mus; 700 kA; Hawk generator; POS opening switches; UV radiation; baffles; current flow; current gain; current-amplification circuit; current-multiplier circuit; distance; efficiency penalty; energy coupling; flashover switches; imploding plasma radiation source load; inside-out flashboard POS; meatgrinder circuit; optimum switching sequence; positive polarity; positive polarity Marx charge; posthole convolute; power generators; quarter period; reduced current level; simplified circuit; surface flashover; switch testing; vacuum closing switches; vacuum flashover surfaces; vacuum opening switches; Circuit testing; Coupling circuits; Electron emission; Flashover; Inductors; Plasmas; Rough surfaces; Surface roughness; Switches; Switching circuits;
Conference_Titel :
Plasma Science, 2002. ICOPS 2002. IEEE Conference Record - Abstracts. The 29th IEEE International Conference on
Conference_Location :
Banff, Alberta, Canada
Print_ISBN :
0-7803-7407-X
DOI :
10.1109/PLASMA.2002.1030432