Performance of Single-Stage and Dual-Stage EV Battery Chargers for G2V and V2G Operation

Abstract

In recent years the growth of electric vehicles has increased day by day and this encourages the different G2V, V2G, V2V, V2L, and V2H technologies. In this paper, discussed the bidirectional power flow from the grid to the vehicle or vice versa. V2G technology is very beneficial during peak load periods, voltage regulation, and improvement of power system stability. To implement this V2G technology, it required proper management of the electric battery charger and the charger is capable of flowing the power in either direction. This paper shows the single-stage and dual-stage charger topology to flow the power in either direction i.e. G2V or V2G. This paper also shows the battery can be charged using constant current and constant voltage charging methods. In the single stage, use only the PFC circuit to charge or discharge the battery. In the dual-stage, an active bridge rectifier for AC to DC conversion with an L filter in series with the source has been used and for the next stage, a bidirectional DAB converter with an LC filter for DC to DC conversion is used and a separate control strategy for battery charging & discharging. This paper shows the battery control strategy can charge or discharge the battery at constant current and constant voltage. The performance of this single-stage and dual-stage battery charger is verified by simulations in MATLAB/SIMULINK software and the waveform is verified in real-time using the OPAL-RT system.