Analysis of a coupled inductor for zero-current transition boost converters

This paper presents an analysis of a coupled inductor for zero-current transition (ZCT) converters. In order to reduce switching losses and noises, a soft-switching technique is adopted. It is suitable for the pulse-width modulation (PWM), because the resonant transition is very short and it is independent of the switching frequency. We adapt a coupled inductor which consists of a boost inductor and a resonant inductor to ZCT converters. To analyze and simulate a magnetic field distribution of the coupled inductor, the ANSYS software is employed. A prototype converter is implemented by a field programmable gate array (FPGA) and a 2.5 MHz analog to digital (A/D) converter. From the experimental results, the zero-current transition operation of the main switch is confirmed and the efficiency of the converter using the coupled inductor is improved.