A comparative study of on-board bidirectional chargers for electric vehicles to support vehicle-to-grid power transfer

In order to provide stabilization of the utility power supply during peak-load times, the possibility for use of an Electric Vehicle´s (EV) traction battery for energy buffering has been proposed, and an On-Board Bidirectional Charger is required to allow efficient battery charging regimes, whilst enabling power to be fed back to the grid pursuant to necessary standards. Here, an in-depth case-study comparison between the use of the EV motor inverter as the bidirectional charger with low frequency transformer (for galvanic isolation), and the use of a high frequency transformer with associated Dual Active Bridge topologies has been undertaken to identify the merits and issues associated with such technologies