A coreless hybrid magnetic coupling coil structure for dynamic wireless power charging system

A coreless hybrid magnetic coupling mechanism has been studied and designed in the dynamic wireless charging system, through the mathematical model building, the parameter analysis and the model simulation comparison. The mechanism can improve the endurance of the electric vehicles, reduce the times of the power supply of the electric vehicles, and increase the offset ability. First of all, the dynamic model of the magnetic coupling mechanism is established based on the Kirchhoff's law of the voltage and current, and the output power and the system efficiency are deduced considering the driving speed of the electric vehicle. Then, the influence of the mutual inductance between coils on the output power and the system efficiency is deeply analyzed, and the mutual inductance between coils is increased by adding the magnetic potential at a proper position, to propose and analyze a coreless hybrid magnetic coupling coil structure. Finally, the co-simulations are implemented through the finite element analysis simulations to compare and analyze the coil structure performance before and after the optimization. The results show that the designed coil structure can effectively improve the coupling between magnetic fields, and increase the offset ability. The mechanism has the characteristics of the small dynamic output power fluctuation range and high efficiency, and then can realize the stable power supply for the mobile power load. (C) 2020 The Authors. Published by Elsevier Ltd.