Coils and Compensation Circuit Design Reduces Power Pulsation and Optimizes Transfer Efficiency in the Dynamic Wireless Charging System for Electric Vehicles ☆

This paper presents a method for designing coils and compensation circuits to reduce output power pulsation and maximize transfer efficiency in a dynamic wireless charging system for electric vehicles. The transmission lane is designed in short-track and is modularized. Each module has three short-track transmitter coils that are placed closely together along the moving track of the receiver and connected to a single-phase bridge inverter. The designs of the transmitting and receiving coils are analyzed by finite element analysis to reduce the variation of the coupling coefficient. And then the coupling coefficient is analyzed to identify the characteristics of the transmission lane. The double-sided LCC compensation circuit is designed according to the optimum load value to obtain maximum transfer efficiency. The SIC devices are used to improve the efficiency of the 85 kHz resonant inverter. A 1.5kW dynamic wireless charging system prototype is built. Experimental results show that the average system efficiency is obtained at 89.5%, and the output power pulse rate is ±9.5% in the dynamic charging process. Moreover, design results are compared with other similar designs that have been performed to demonstrate the benefits of the proposed design system.