A Fully Soft-Switched PWM DC-DC Converter Using An Active-Snubber-Cell

This paper proposes an active-snubber-cell and its dual circuit to achieve fully soft-switching operation for PWM DC-DC converters. Main switch of the converter achieves both turn-on and turn-off with zero voltage condition; a switch in the proposed cell achieves zero current turn-on and zero voltage turn-off. The main diode is turned-off with zero current and other semiconductor devices operate under soft-switching condition. No additional voltage and current stresses are imposed by the proposed cell. The proposed active-snubber-cell can be applied in a range of PWM DC-DC converters; the guidelines for implementing the proposed cell will be presented. Easy implementation for an interleaved converter makes the proposed cell is suitable for high power applications. The presented operating principle and analysis is verified using a 100 kHz and 1kW prototype of the proposed cell implemented on a boost converter. As a result, the peak efficiency of 98% is achieved.