High voltage surge arrestor testing with enhanced transformer drive

High voltage surge arrestors are used in a variety of applications. In addition to their usual application as protection devices for power systems and equipment, such devices have also been used to control the “Flat top” voltage of pulsed power equipment. Testing of these devices and device stacks at representative voltages is important for both applications. We have built and tested a unique pulsed power system which can test the current response of the devices at voltages from 10-150 kV for pulse durations of up to 15 μsec and currents of up to 6A. This test equipment is able to perform these measurements with a stored energy of only 50 J. The risetime of the system is 2 microseconds, and a unique control system is used to produce a fast risetime into an open circuit without overshoot. This also produces a faster risetime than would normally be produced with a transformer of equivalent size. Detailed results of the development and testing of this pulse generator are presented including the results of testing with series zener diode loads, and with stacks of commercial metal oxide varistors (MOVs).