Characteristics of Buck/Boost Operation in an Isolated DC-DC Converter based on a Phase-Shift-Controlled High-Frequency Inverter

This paper proposes an isolated dc-dc converter for realizing an independently control of buck/boost operation by the primary and secondary side, respectively. The proposed circuit consists of two phase-shift controlled high-frequency inverters. The inverter has a snubber inductor and a snubber capacitor for realizing zero-current and zero-voltage switching for all switching devices when phase-shift control method is applied. Therefore, the inverter and rectifier can independently operate with the phase-shift control method to achieve buck/boost operation. This paper presents the circuit configuration and basic operation principle of the proposed circuit. Validity of the operation principle is confirmed by a 100-V, 600-W experimental setup with half and 1.5 times output voltage conditions.