An Improved Control Method for the DC-DC Converter in Vehicle to Grid Charging System

Abstract

This paper presents the charging station of an electric vehicle (EV) battery in smart grid system for compensating of active power. By injection of the active power from the bidirectional vehicle to grid (V2G)charger, there is a reduction of overloading of transformer and voltage profile improvement. A new control strategy is used for bidirectional electric vehicle charger. The charger consists of a two stage bidirectional power converter is designed for the grid to vehicle(G2V) charging and vehicle to grid(V2G) discharging. The switching of bidirectional DC-DC converter modules of charging station control the charging of the EV battery with constant current and discharging with variable current. The performance of the bidirectional controller prototype with current control strategy is validated through simulation in MATLAB/simulink environment under different load condition. The control strategy incorporates both dynamic charging and discharging.