Comparison and Verification of Control and Filter Methods for Efficiency and Current Harmonic Components of a Dynamic Wireless Power Transfer System

Abstract

The reduction of the leakage magnetic field is a critical problem in achieving the realization of a dynamic wireless power transfer system for battery electric vehicles. In particular, besides the leakage magnetic field of the fundamental component, the harmonic components must also be suppressed. In Japan, the regulation values of the leakage magnetic field are set according to the Radio Law. Accordingly, two methods have been proposed to reduce the harmonic components of the leakage magnetic field: a control method and a circuit method. In the control method, an inverter and rectifier are controlled using a phase shift that can reduce a specific order component. In the circuit method, an LCC circuit with low-pass filter characteristics has been investigated for each of the transmitter and receiver coils has been studied. In this paper, we compare the control method and the circuit method using the same coil and verify how the efficiency and the harmonic components of the current change with respect to the conventional square wave drive.