Single-stage half-bridge converter using a coupled-inductor

A single-stage half-bridge flyback converter with high power factor and high efficiency is proposed. A half-bridge flyback converter is coupled to the line voltage for power factor correction (PFC) and driven in complementary control for zero-voltage switching. The proposed PFC can achieve almost unity power factor and ripple-free input current using a coupled inductor. The half-bridge DC-DC converter is analysed and optimised for high power efficiency. Experimental results for a 200 W converter at a constant switching frequency of 100 kHz are obtained to show the performance of the proposed converter.