Impedance Plane Based Interoperability Assessment of Two High-Power 50 kW WPT Systems for EV Charging

For the economic success and extensive application of Wireless Power Transfer (WPT) systems, the interoperability of high-power inductive charging systems is crucial. As the standard is only defined up to 11 kVA, interoperability studies of highpower systems (e.g. 50 kW) are rare. For this reason, this paper provides an interoperability assessment of two independently designed 50 kW high-power WPT systems. The study is done by using an impedance plane method which allows system limitations to be considered, e.g. of the inverter or the magnetic coils, along with system characteristics such as leakage fields.The results show that good interoperability is generally achieved. However, this paper also discusses different limitations and possible consequences such as degradation of the transfered power under certain operating conditions, in systems without secondary impedance control.