Novel Coil Detection Method for Dynamic Wireless Power Transfer for Electric Vehicles

This paper addresses the problem of ineffective transmission in dynamic wireless power transfer (DWPT) systems for electric vehicles by proposing coil detection for DWPT based on the foreign object detection technology of static WPT. The proposed system allows operation within the optimal transmission range for high magnetic field coupling. An operating frequency range of 80-90 kHz ensures system safety during operation. The voltage change generated by the detection circuit corresponding to changes in mutual inductance is used as an index to initialize the primary coil, thereby reducing unnecessary energy transmission. This study also analyzed the series-series and double capacitances and inductances-series (LCCL-S) topologies. The LCCL-S topology allows the input impedance of the system to remain fixed without reflected impedance, preventing the primary circuit from being affected by mutual inductance and thereby protecting the system components. Both simulations and experiments were performed to validate the proposed system. The experimental results indicate that the proposed method can be used to reduce unnecessary energy loss during DWPT in modern electric vehicles.