Single Phase High Power Density MISN PFC Converter

CHB PFC rectifier with multiple floating output buses limits the architecture of downstream DC-DC converters, and leads to common mode noise issues after considering the parasitic capacitance of DC-DC stage. In this paper, a single output-bus multilevel PFC converter with modular inductive switching network (MISN) is proposed. Since the dc output bus is connected to the ac bus through a line frequency rectifier, the high frequency voltage step between the dc bus and ground can be eliminated, which was a big issue in CHB topology. Based on the operating principle of this topology, a closed loop control strategy is proposed and discussed. Furthermore, the efficiency and volume optimization methodology of MISN converter is also provided and verified by a 3kW single phase prototype. In the prototype, the peak efficiency exceeds 99% and the power density achieves 280W/in
³
.