Analysis of Wireless Power Transfer Technique in Electric Vehicles for Different Coils without & with Ferromagnetic Core

Electric Vehicle (EV) charging stations are gaining popularity to meet the needs of the hour for EVs.In India, the number of EV charging stations almost doubled from 6586 to 12,146 in the span of the last one year, as per the statistics given by the Ministry of Power, India.The Ministry of Heavy Industries approved a large subsidy of Rs. 800 crores to install 7,432 EV charging stations.Wireless EV charging is advancing very fast because of its advantages of reducing wear and tear and increasing convenience and facility to charge the vehicle while in motion.This paper analysed the Inductive Wireless Power Transfer (IWPT) method for different coil structures.The operating principle of IWPT is similar to that of the transformer; only the ferrite core is absent here.The absence of ferromagnetic material leads to a low coupling coefficient.Therefore, a compensation circuit becomes necessary to compensate for the low coupling coefficient.However, a ferrite core in the inductor coil exhibits higher magnetic permeability than the air-cored inductor.The magnitudes of the inductances also depend on the coils' shape.In this research, the circular and rectangular shape of the transmitter and receiver coils have been analysed in the Ansys Maxwell environment.The finite element analysis (FEA) was carried out in Magnetostatics mode.The mutual and self-inductances for the rectangular coil are higher than that of the circular coil, considering the same number of turns and current magnitude in both coils.