A Coordinate Positioning Technique Based on Region Partitioning for EV Wireless Charging System

The performance of wireless charging systems is very sensitive to the relative position of couplers. A small displacement between the transmitting and the receiving coils may lead to severe efficiency drop and degradation in system performance. Therefore, it is necessary to include a positioning-technique-based parking guiding program in electric vehicle (EV) wireless charging systems. To offer fast and clear location information of the couplers to the driver or automatic parking program, a coordinate positioning-technique based on region partitioning for determining the relative position between the transmitting and receiving coils as well as the correct moving direction of the receiving coil is proposed in this article. Meanwhile, a simple exciting circuit is also proposed to energize the source coil. Therefore, the proposed positioning system consists of the transmitting coil, receiving coil, two auxiliary coils, and the corresponding low-power converters. With the proposed technique, an EV can move to the near-perfect-coupling zone. Theoretical analysis and experimental verifications are provided.