Design of a Three-Coil-Based Wireless Charging System for Electric Vehicles

Wireless power transmission (WPT), also known as wireless charging technology, brings convenience to people's lives, particularly in the new energy vehicle industry, where the advantages of wireless charging over wired charging are more evident. However, traditional single-to-single WPT modes present various challenges, including high voltage and current stresses, substantial power loss, and excessive heat generation. These issues primarily stem from the significant power demands of electric vehicles. To address this issue, this text proposes a single-transmitter triple-receiver WPT system, where three receiving coils are connected in series and collectively deliver power to a load. This configuration enhances the output power while reducing the voltage and current stress, thereby improving system efficiency. Furthermore, this approach eliminates the need for an additional DC/DC circuit for voltage boosting, resulting in a simple and reliable circuit design. The main work involves modelling the system and performing parameter characteristic analysis. After selecting appropriate parameter values, circuit simulations are conducted using the Simulink platform. Based on the simulation results, the system exhibits the following parameters: an input voltage of 200V, an output voltage of 385V, all three currents are within 20A, resulting in a power output of 7382 $W$ , and an efficiency of 81%.