Modeling and implementation of a new ZCS interleaved bidirectional buck-boost DC-DC converter for energy storage systems

This paper deals with a new soft-switched interleaved bidirectional DC-DC converter for energy storage systems. The conventional interleaved bidirectional converter incorporates with an additional auxiliary circuit to attain soft turn-on operation of the main switching devices (IGBTs). The proposed converter is operated in boost and buck modes with zero current switching turn-on operation in order to have minimized turn-on losses by adding auxiliary switches, inductor and capacitors to the main interleaved converter module. The proposed interleaved converter has advantages like reduced switching power losses, device count and improved efficacy. The operating principles and theoretical analysis of the interleaved topology under buck and boost modes are presented in detail. Design simulation analysis and its experimental results were executed using 1-kW, 50-kHz laboratory prototype. The converter's soft-switching characteristics and its performance were also demonstrated.