A Transmitter Array Control Method for Suppressing Magnetic Field Leakage from Wireless Power Transfer Systems

Magnetic resonant coupling wireless power transfer (MRC- WPT) using transmitter arrays is expected to be applied to power electric vehicles and electronic devices. Transmitter arrays can maintain power transfer efficiency despite lateral misalignment between the transmitter and receiver. However, methods of using transmitter arrays while reducing magnetic field leakage have not been studied. A new method of using transmitter arrays is necessary for electromagnetic compatibility and user safety. In this study, we optimized the input currents at transmitter arrays and the load at the receiver to reduce magnetic field leakage and maintain power transfer efficiency even with lateral misalignment between the transmitter arrays and the receiver. Simulations showed that the proposed method can reduce magnetic field leakage by more than 10 dB and 38 dB, with and without ferrite plates, respectively, compared to the existing method of maximizing power transfer efficiency.