Potential of using GaN devices within air cooled bidirectional battery chargers for electric vehicles

Abstract

This paper deals with the advantages of GaN devices for bidirectional battery chargers for plug-in hybrid electric vehicles and electric vehicles that are connected to the singlephase European ac grid. Compared to a charger with silicon devices a higher power density can be realized because of the lower switching losses of GaN devices that enable higher switching frequencies. A state-of-the-art battery charging systems will be described and the differences and advantages of fast switching GaN devices compared to standard silicon ones will be pointed out. The presented topology allows bidirectional power flow. Therefore, this charger can be used to stabilize the utility grid. An overview of the different components of the battery charger and their design aspects are presented in this paper.