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Description:
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Generally , the limiting component in a pulsed power system is the switch This is due to the fact at some point , the switch transfers all of the energy in the system High voltage and current create a rough environment for switch electrodes and insulators . In previous studies of switch reliability and lifetime , electrode erosion has received much attention . This investigation deals with the mechanisms behind electrode fracture , which presents an immediate problem , rather than erosion , which has long -term effects on switch performance .
The switches under study are spark gaps with graphite electrodes . The spark gap closes when an electric arc forms between the electrodes , and current conduction begins Strong mechanical forces are generated as the arc forms and impact the electrodes . The purpose of this research is to determine the dominant pressure mechanism of electrode fracture , and the propagation of the pressure wavefront through the electrode .
Energy is stored in a 5 kJ , 60 kV capacitor , and shorted through the spark gap . This is done to duplicate prior experimental work at Physics International Company . Operating parameters , such as gap spacing , air pressure , charging voltage , inductance , and magnetic pulse shaping , are varied , and mechanical pressure is measured using a strain gage mounted on a ceramic bar . Experimental data from the strain gage is compared to theoretical modeling done in Mathcad and PSPICE . |