Three-phase power module bridge type auxiliary resonant AC link snubber-assisted three-phase soft switching inverter

This paper presents a novel prototype of the three-phase power module bridge package type auxiliary resonant AC link snubber circuit for the three-phase voltage source type sinewave soft switching PWM inverter using IGBT power module which operates under instantaneous space voltage vector modulation scheme. The operating principle of a novel prototype resonant AC link snubber circuit in addition to its unique features are described for current source load model during one switching period which is equivalent to the three-phase voltage source type inverter with LPF, along with its design approach based on the simulation data. The steady-state performance evaluations of space vector modulated three-phase voltage source type sinewave soft switching inverter incorporating a new prototype circuit of three-phase active auxiliary resonant AC link snubber is illustrated and discussed as compared with those of three-phase voltage source type sinewave hard switching PWM inverter with a space voltage vector modulation strategy. The power loss analysis of the three-phase soft switching PWM inverter using IGBT power modules is actually evaluated and discussed on the basis of the conduction power losses based upon the measured v-i characteristics in addition to all the switching power losses of each IGBT with antiparallel diode.