A SiC MOSFET-Based Auxiliary Resonant Commutated Pole Inverter with Simple Auxiliary Resonant Circuit and Improved Modulation Strategy

In this paper, a simple auxiliary resonant circuit is adopted to realize an auxiliary resonant commutated pole soft-switching inverter, and its modulation strategy is improved simultaneously. It can realize ZVZCS turn-on and ZVS turn-off of main switch, and ZCS turn-on and ZVS turn-off of auxiliary switch. Due to the characteristic that the turn-off loss of SiC MOSFET is far lower than the turn-on loss, the use of capacitor is avoided, the volume of inverter is reduced, and there is no neutral point potential drift. The modulation strategy of soft-switching inverter is simple, the control is reliable, and the voltage stress is not higher than the DC power supply voltage. In this paper, a modulation strategy is confirmed and then improved, the operation modes and equivalent circuit of soft-switching inverter under the two modulation strategies are analyzed. Further, the method of designing various electronic components and modulation strategy parameters is proposed. At last, taking SiC MOSFET as switching device, a simulation platform is built, and the effectiveness of the inverter is verified by simulation.