Design and Modeling of Auxiliary Misalignment Detection Coils for Dynamic Wireless Electric Vehicle Charging Systems

Abstract

Due to the inherent misalignment variations in dynamic wireless electric vehicle (EV) charging systems, it is essential to implement effective misalignment detection and correction techniques to maximize the amount of energy received by the EV. A misalignment detection system consists of detector coils or sensors, and the corresponding detection circuitry. In this work, the design details of the auxiliary misalignment detection coils are presented. In particular, the paper investigates the effect of the number of turns of the auxiliary coils, their turn-to-turn spacing, and their positions relative to the edges of the secondary coil, on their lateral misalignment detection capability. Based on the conducted simulations, it is observed that increasing the number of turns as well as the turn-to-turn spacing of the auxiliary coils both significantly improve their misalignment detection capability by improving the resultant mutual inductance variations with lateral misalignments. Also, the optimal position of the auxiliary coils is determined to be 200 mm from both edges of the secondary coil.