Dual-Input Interleaved Bidirectional DC-DC Converter for Light Electric Vehicles

This article proposes a dual-input interleaved bidirectional dc-dc converter for light electric vehicles (EVs). The low-voltage side of the proposed converter consists of batteries and supercapacitors (UCs). One set of complementary PWN signals with a phase difference of 180 degrees is used to control the switch of the proposed converter to achieve the desired voltage gain with a fixed duty cycle. Hence, compared to the interleaved topology realized by converters in parallel, the proposed converter can achieve low-side current continuity and reduce the input current ripple by using the complementary PWN signals strategies. Moreover, the voltage gain can be further improved by adjusting the turns ratio of the coupled inductor of the converter, meanwhile, the voltage stress on the switches can be reduced. The operational principles of the proposed converter are introduced. An experimental bidirectional converter with 500 W is implemented to verify the feasibility of the proposed bidirectional converters. The test results show that the highest efficiency of the step-up and step-down modes is 98% and 96.9%, respectively.