Crowbar circuit protection of high voltage power supply of plasma filled HPM source

The operation voltage of high voltage DC power supply of plasma filled high power microwave source-PASOTRON is from –70kV up to –150kV, the total current is about 300A, while the modulator(current 60A, pulse width 60~120m s) is operating suspended on the HV-DC. In practice, if the strike arc occurs, there is a strong potential to destroy the microwave tube, high voltage DC power supply, modulator or/and modular circuit of the system. The protection system of the power supply, therefore, plays an important role in the operation of system. The special designed HV crowbar and a simple self-triggering circuit is applied, and a satisfied protection result is achieved. The experiments show that, 98% of the energy of the filtering capacitor would be bypassed by the crowbar after 150ns of the st