Auxiliary resonant snubber bridge-leg associated soft-switching PWM inverter type DC-DC converter family with bidirectional active switches and voltage clamping diodes

Abstract

A prototype of voltage-source soft-switching PWM inverter-type auxiliary resonant bridge-leg link snubbers is proposed with bidirectional active power switches and voltage clamping diodes for a new high-power high-voltage application. The voltage clamping diodes in the active resonant snubber are more effective in protecting the bidirectional active switches in the bridge-leg linked auxiliary resonant snubber from surge voltage spikes caused by energy stored in the auxiliary quasiresonant inductors and inductive parasitic wiring components. A variety of resonant snubber circuit topologies with voltage clamping diodes are presented and demonstrated. As an example of the variations of the proposed auxiliary active resonant-commutation snubber topologies, operation of a single-IGBT bidirectional switch with two voltage clamping diodes is analysed and discussed in detail for the auxiliary resonant bridge-leg link snubbers. The operating performance of the new active auxiliary resonant snubber-associated inverter-fed DC to DC power converter with voltage clamping diodes is practically demonstrated and evaluated to verify its effectiveness for a high-power high-voltage X-ray generator.