Small signal analysis of a novel type of ZVS DC-DC converter for fuel cell

Abstract

This paper first introduces a novel type of current-fed push-pull ZVS dc/dc converter. Compared with the traditional Phase-shifted ZVS converter used in fuel cell system, this new converter can reduce the semiconductor switching losses and EMI noise and increase the circuit conversion efficiency. This paper also presents a detailed derivation of small-signal model using state space averaging technique. Then it designs the parameters of PI regulator for the current-loop and voltage-loop based on small-signal model. Finally, it gives the simulation model of the dual closed-loop control system with PSIM simulation software. The simulation results show that the designations of small-signal model and two controllers are feasible.