Optimal Matching Reactance Design and Validation in Wireless Power Transfer System for Electric Vehicle Based on SAE J2954-RP

Wireless power transfer (WPT) is foreseen as a suitable technology to provide charging without cables to electric vehicles. The charging requires a specific charging profile for different type of battery. In addition, the loading condition of the charging circuit could change drastically as following the charging profile. Due to the dependencies on loading condition, the transmission efficiency of a WPT system could degrade during the charging process. Nevertheless, the sensitivity of efficiency to loading condition could be reduced with proper design of compensation network, e.g., LCC. In this paper, a SPICE-simulation based optimization flow is demonstrated for matching reactance optimization for a WPT system following the Society of Automotive Engineers (SAE) J2954 recommended practice (RP). Based on the method we proposed, it is possible to obtain the optimal reactance value for multiple loading conditions regarding transfer efficiency. The proposed method and result are verified by experimental measurements.