Wireless charging is of great significance for accelerating the promotion of electric vehicles. In order to explore the influence of foreign object on wireless charging system, the circuit model and the magnetic circuit model are established to simulate the working status of LCC-LCC wireless charging system under the interference of foreign object. The circuit model is used to analyze the interference of the conductivity of foreign object on the system while the magnetic circuit model is used to analyze the interference of the magnetic properties of foreign objects on the system. The results prove that foreign object will increase power loss, change the equivalent parameters of the coil and destroy the magnetic field in the energy coupling area. The work of this paper has guiding significance for the design of foreign object detection system based on detection coils.

electric vehicle; foreign object; influence; wireless charging;