An Auxiliary Resonant Pole Soft-Switching Inverter With Low Pre-Charge Current

The precharging process of the auxiliary circuit of the auxiliary resonant pole inverter increases the current stress of the switch and the loss of the inverter. To overcome these problems, this article proposes an auxiliary resonant pole soft-switching inverter with low precharging current. In contrast to the existing auxiliary resonant pole soft-switching inverter, this inverter can effectively decrease the precharging current of the auxiliary circuit, thus reducing the current stress of the switch, lowering the conduction loss of the switch, and improving the inverter efficiency. Moreover, the main switch and auxiliary switch of this inverter share a common resonant capacitor, which reduces the loss resulting from reactive energy conversion of the auxiliary commutation circuit so that the inverter achieves the purpose of simplicity and efficiency. On the basis of the equivalent circuit diagram in each operating mode, the operating mechanism of this inverter is analyzed. In addition, the soft switching conditions and the parameter optimization design method of this inverter are provided. Finally, the validity of this inverter is experimentally verified.