Enhancement of Misalignment Tolerance in Multi-Transmitter Wireless Electric Vehicle Charging System Through an Optimal Transmitter Stimulation

In wireless power Transfer (WPT) based Electric vehicle (EV) charging system the efficiency of power transfer gets reduced due to misalignment between transmitter and receiver coil. Multi-transmitter coil approach instead of single transmitter can improve the misalignment tolerance. This paper presents four transmitter coils with a single receiver coil to improve the misalignment tolerance with optimal stimulation. Instead of stimulating all four transmitter coils, only one transmitter coil is stimulated, whichever is almost or exactly aligned to the receiver coil. Based on the current distribution over, all the Tx coils the optimal Tx coil is identified without using additional sensors on the Rx side. The Tx coils' current distribution is calculated theoretically using mutual inductance obtained from ANSYS-Maxwell simulation of the coil geometry. Using these current distribution data, the corresponding transmitter coil is stimulated optimally, improving the transfer efficiency even with 50 percent misalignment.