Frequency-Selective Suppression Method of Harmonic Magnetic Field for Double-Sided <i>LCC</i> Wireless Power Transfer Systems

This letter proposes a method for selectively reducing harmonic magnetic field. When a wireless power transfer (WPT) system transmits power using a magnetic field as a medium, a leakage magnetic field inevitably occurs nearby. Meanwhile, a square wave voltage is generated by high-frequency switching of the inverter or rectifier used in the WPT system, and this square wave voltage is divided into fundamental and harmonic components. Harmonic components are radiated through the coil and can cause interference in other electronic devices, resulting in an electromagnetic interference (EMI) problem. The proposed method selectively and completely reduces harmonics by modifying the double-sided <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCC</i> topology. The approach was verified through an experiment, showing that the third harmonic and fifth harmonic can be reduced by 16.03 and 18.27 dB, respectively.