Multi-input DC/DC converter with ripple-free input currents

A multi-input DC/DC power converter with ripple-free input currents is proposed in this paper. In order to reduce the cost and size of the input inductors and achieve the electromagnetic interference (EMI) suppression, the coupled inductor technique is employed to obtain ripple-free input currents. With phase-shifted pulse width modulation (PWM) control, the converter can draw power simultaneously from two different voltage sources and deliver it to the load. The operation principle of the proposed converter has been analyzed in detail. The output voltage regulation and power flow control can be achieved by the proposed phase-shifted PWM control. Moreover, all the power switches in the proposed converter can be operated with either zero-voltage-switching (ZVS) at turn-on transition or zero-current-switching (ZCS) at turn-off transition. A prototype converter with two different DC voltage sources has been successfully implemented. Hardware experimental results are presented to verify the performance of the proposed multi-input DC/DC converter.