Electromagnetic Interference Issues of a Wireless Power Transmission Converter

Nowadays inductive charging is a new approach to transfer electrical energy from a electrical supply to loads and batteries without any electrical physical interface. However, it is an important issue. It is that inductive charging technologies may have electromagnetic compatibility (EMC) issues caused by radiated field and leakage current flowing through stray capacitors. For example, if several vehicles charge their batteries simultaneously in an electric charge parking, electromagnetic interference (EMI) can be a major issue. The EMI issue associated to wireless power transmission technology is less studied or even has not been evaluated. In this paper, the EMI of wireless power transmission technology is highlighted and for the first time evaluated from a new aspect. The possible parasitic paths are identified simply. In addition, effective high frequency models for each part of the inductive charger are presented. At first, the lowest EMI technology for wireless charging is chosen and simulated. To overcome EMI and leakage current problems, this paper also suggests using new passive EMI filter topology. Simulation results show the necessity of considering EMI issue. The effectiveness of proposed methods based on the leakage current studding, are shown.