Design and Testing of Wireless EV Charging System with Improved Lateral Misalignment Tolerance

The utilization of wireless power transfer (WPT) for on-the-move, i.e. dynamic, charging of electric vehicles (EV) is gaining an increasing popularity with the increase of the percentage of EVs in the market. This is because, dynamic wireless charging (DWC) systems offer solutions to reduce the expected congestion at plug-in EV charging stations and reduce the range anxiety of EV drivers, by allowing them to recharge their batteries while driving. Nevertheless, with the inevitable misalignments during the vehicle’s motion, this work proposes and implements a high misalignment tolerant WPT system for DWC of EVs. The proposed system uses double-sided LCC compensation circuits with a dual-secondary receiver coil, namely a DDQ coil. The two sub-coils on the secondary side help in mitigating the undesirable fluctuations in the coupling coefficient and increase the misalignment tolerance of the system. In this paper, details of the design and implementation of a small-scale prototype of an EV DWC system are presented. In particular, a primary side H-bridge inverter is implemented, and the use of two secondary side circuits, connected to the two secondary side sub-coils, is demonstrated to show the improvement in misalignment tolerance offered by the secondary DDQ coil. A close correlation between the simulation and experimental results is observed and the experimental output is verified.