Bi – directional trans – Z source boost converter for G2V/V2G applications

Abstract

The bidirectional power conversion with simple and unified bidirectional control, modular architecture, low common mode currents, low ripple, effective use of storage element and low voltage stress on the switches are some of the important features requisite for Vehicle to Grid (V2G) and Grid to vehicle (G2V) interface for Electric Vehicle (EV). This paper proposes a new approach to circuit configuration of the converter for incorporating all the aforementioned bottlenecks to realize a robust converter for both V2G and G2V interface with LVDC grid. The proposed topology employs a simple and unified bidirectional control algorithm capable of smartly charging (G2V)/discharging (V2G) the battery stacks with customized rates depending on the SoC’s of battery stacks with negligible common mode currents. The control scheme automatically drives the converter to use the Trans-Z impedance network the moment higher gain is requisite during low charge conditions of batteries or any transients on the LVDC grid. The proposed modular bidirectional converter is tested through rigorous simulation to affirm high efficiency operations over a broad range of duty cycle.