Z3 class 50 kW Bidirectional IPT charger for EV

This paper presents a 50 kW bidirectional wireless power transfer system designed to transfer power through a 250 mm airgap to charge a 400 V electric vehicle energy storage system. The charger is based on a series-series compensated inductive power transfer system supplied from the grid, and SiC power semiconductors are employed to deal with the high power transfer and high switching frequency. A control schema is presented to control the power transfer to the energy storage system with both constant-current and constant-voltage modes from the infrastructure side with minimum information from the vehicle side. Experimental tests have been performed to validate the desired target efficiency along the whole power battery voltage range. Furthermore, magnetic field measurements are incorporated to comply with the ICNIRP guidelines.