Clamping Circuit for Auxiliary Resonant Snubber-based Soft-Switching Inverter to Suppress Over-voltage of Auxiliary Switches

Auxiliary resonant snubber inverter (ARSI) is a kind of soft switching inverter, which has the advantages of low current stress, fixed switching frequency and decoupled control. However, due to the existence of parasitic parameters, the auxiliary switching devices have the problem of overvoltage in practical circuits. Besides, the overvoltage mechanism of the auxiliary resonant soft switching inverter has not been explored. Therefore, this paper analyses the overvoltage mechanism of auxiliary switching devices of auxiliary resonant soft switching inverter. In addition, a suppression method is proposed to suppress the overvoltage in practical circuits. Firstly, two kinds of auxiliary circuit models including junction capacitance and on-resistance are established in this paper, which are single branch and separate branch. The overvoltage mechanism of auxiliary switching devices is introduced. Secondly, on the basis of the mechanism analysis, an overvoltage suppression method with clamping diode is proposed. Finally, the theoretical analysis is verified by simulation and experiment.