Coil Switching Method for Multi-Coil Transmitter Optimal Control System Applied to Planar Wireless Power Transfer System

抄録

This paper presents a coil-switching method for a multi-coil transmitter optimal control (MTOC) system applied to a planar wireless power transfer system. The MTOC system achieves constant power transmission with maximum efficiency independent of the position and orientation of the receiver. MTOC requires the simultaneous operation of multiple transmitter coils, and therefore, the number of inverter legs must match the number of activated coils, increasing system cost. To address this issue, the proposed method employs changeover switches between the transmitter and receiver, enabling a transmitter with many coils to be driven by an inverter with only a few legs while realizing MTOC operation. The coil-switching strategy operates in the search and transmission & tracking modes. In the search mode, the system detects the receiver coil and identifies the coil-combination of the transmitter coils near the receiver coil. In the transmission & tracking mode, the system performs MTOC-based power transmission while continuously tracking the position of the receiver. The effectiveness of the proposed method is experimentally demonstrated using a hexagonal honeycomb-arrayed transmitter coil configuration.