Study and Implementation of a Single-Stage Current-Fed Boost PFC Converter With ZCS for High Voltage Applications

The study and implementation of a single-stage current-fed full-bridge boost converter with power factor correction (PFC) and zero current switching (ZCS) for high voltage application is presented in this paper. The single-stage current-fed full-bridge boost PFC converter can achieve ZCS by utilizing the leakage inductance and parasitic capacitance as the resonant tank. The variable frequency control scheme with ZCS is used to regulate the output voltage and achieve high power factor. The operating principle, steady-state analysis, and control method of this single-stage AC-DC PFC converter are provided. Also, the ZCS operational conditions under various operational conditions are discussed. The design guidelines are given and verified by a laboratory prototype converter with 200 ~ 240 Vrms input voltage and a 4 kV/1.2 kW output. In order to reduce the switching losses, the highest switching frequency is constrained at 160 kHz. So, the switching frequency of the prototype converter is 50~160 kHz. The measured power factor is 0.995 and the efficiency is 87.4 at full-load condition with an input voltage of 220 Vrms. The laboratory prototype converter can be operated at ZCS under full range by carefully designing the circuit parameters.