A ZCS-PWM interleaved forward converter

This paper proposed a zero-current- switching pulsewidth-modulation (ZCS-PWM) interleaved forward dc/dc converter. The proposed ZCS-PWM interleaved forward converter combines the conventional pulse-width-modulation technique and soft commutation technique. The main switch and auxiliary switch operate at zero-current-switching turn on and turn off, and the all passive semiconductor devices in the proposed converter operate at zero-voltage-switching (ZVS) turn on and turn off. The proposed converter uses two ZCS-PWM interleaved forward converter with interleaved operation to increase the output power and reduce the output ripple. Besides operating at constant frequency and reducing commutation losses, the proposed converter has no additional current stress and conduction loss in the main switch in comparison to the conventional hard switching forward converter counterpart. The power transformer can self-reset without the conventional reset winding. The principle of operation, theoretical analysis, and experimental results of the proposed ZCS-PWM interleaved forward converter, rated 500W and operating at 40 kHz, are provided in this paper to verify the performance of the proposed converter.