Design and modeling of Phase Shifted Full Bridge DC-DC Converter with ZVS

The demand for robust and efficient power converters is driving the research of various DC-DC converter topologies and enhanced control strategies. In this paper, comparative analysis of full-bridge LLC (Inductor-Inductor-Capacitor) and phase-shifted full-bridge converters, center-tapped and bridge rectifiers, synchronous and passive rectifiers have been performed. Zero voltage switching (ZVS) resonant considerations for the phase-shifted full-bridge (PSFB) have been studied. A 1kW phase-shifted full-bridge DC- DC ZVS converter has been designed and modeled. Aspects of the selection of components of an isolated DC- DC converter studied and discussed. The theoretical design of a converter is compared with and validated by simulation. Design aspects of shim inductor and effect of changing the position of shim inductor and clamping diodes is discussed. With correct position of shim inductor and clamping diodes primary current is reduced which result in reduced conduction losses of switches and increase in efficiency. The converter demonstrated 94% efficiency, and relatively stable operation at 200 kHz.