Zero-Voltage Soft-Switched PWM DC-DC Power Converter Modification Operating at Reduced Conduction Losses for Distributed Power Supply

An improved soft-switching PWM full-bridge DC-DC converter is presented. This employs a tapped inductor for low-pass filter to minimize a circulating current flowing through the transformer and switching devices. By using the tapped inductor and a saturable reactor(s), the converter achieves soft-switching with both low commutating and low circulating currents resulting in low switching and conduction losses. The effective performance of the converter is experimentally confirmed with a 100KHz-500W breadbord.