The ZVS-PWM active-clamping CUK converter

A CUK converter featuring clamping action, pulsewidth modulation, and soft-switching commutation is proposed to overcome the limitations of the conventional CUK converter. As the resonant circuits absorb almost all parasitic reactances of switches, including transistor output capacitances, this converter is suitable for high-frequency operation. Principle of operation, theoretical analysis, and simulation results are presented in this paper. Experimental results, taken from a laboratory prototype rated at 400 W, input voltage of 150 V, output voltage of 200 V, and operating at 100 kHz, are also presented. The efficiency obtained at full load of the power stage was 93%.