Three-phase Wireless Power Supply System Using Matrix Converter

This paper proposes a three-phase wireless power transfer (WPT) system with three-phase to three-phase matrix converter to integrate the transmission coils with the power converter on the transmission side suitable for high temperature operation. The proposed system expands a lifetime of the WPT system due to eliminates a electrolytic capacitor. Furthermore, the space installed the WPT system is saved. A novel hybrid commutation method, which is suitable for the WPT system with a resonant characteristic, is employed to avoid the commutation failure of the matrix converter. The strategy of the proposed hybrid commutation is based on an estimation of the current direction considering to the resonant characteristic and the elimination of the commutation in the critical area. The proposed commutation method achieves AC input-current THD of 4.7% with the resonant three-phase load without any current sensor on the high-frequency side. Furthermore, the proposed WPT system achieves a maximum system efficiency of 88.2% under condition of 400-V AC input 400-V DC output and 4-kW output power.