Energy-Efficient and Adaptive Design for Wireless Power Transfer in Electric Vehicles

Wireless power transfer (WPT) could revolutionize global transportation and accelerate growth in the electric vehicle (EV) market, offering an attractive alternative to cabled charging. Coil misalignment is inevitable due to driver parking behavior and has a detrimental effect on power transfer efficiency (PTE). This paper proposes a novel coil design and adaptive hardware to improve PTE in magnetic resonant coupling WPT and mitigate coil misalignment, a crucial roadblock in the acceptance of WPT for EVs. The new design was verified using ADS, providing a good match to theoretical analysis. Custom designed receiver and transmitter circuitry was used to simulate vehicle and parking bay conditions and obtain PTE data in a small-scale setup. Experimental results showed that PTE can be improved by 30% at the array's center, and an impressive 90% when misaligned by three-fourths of the array's radius. The proposed novel coil array achieves overall higher PTE compared to the benchmark single coil design.