Optimized design of the detection coils for the metal foreign object detection system applied to wireless power transfer

Abstract

In order to improve the safety and reliability of electric vehicle wireless charging, foreign object detection is an indispensable auxiliary function. In this paper, the equivalent model of foreign object detection circuit is firstly established, and then the foreign object detection principle based on active detection coil is analyzed from the angle of the circuit and magnetic circuit. Then the optimization scheme of metal foreign object detection coil is proposed through simulation comparison and analysis. The results show that the design proposed in this paper can increase the maximum value of |Bz| to 3.6 mT, effectively improving the accuracy of metal foreign object detection.

Keywords

• Metal foreign object detection
• Detection coil
• Wireless power transfer
• Optimized design