Effects of EV Steel Floor on Leakage Flux for High Power Wireless Charging Systems

This paper explores the accuracy of modelling electric vehicle (EV) steel flooring and assesses its interaction with leakage flux from an eddy current heating and emissions perspective in a high power inductive power transfer (IPT) wireless charging system (WCS). Existing literature presents aluminium (Al) shielding as a method of reducing leakage flux emissions adjacent to the EV body during charging. Findings in this work suggest Al shielding is effective at reducing eddy current heating, but ineffective at reducing leakage fields adjacent to the EV body in the presence of a steel EV floor. Experiments were performed to assess eddy current and leakage flux behavior and to verify finite element analysis (FEA) models. Recommendations are made regarding how steel can be modelled in FEA software in the absence of a detailed material model and methods are presented.