Research on the characteristics of compensation networks in wireless charging system for electric vehicle based on magnetic coupling resonance

As the core of the resonant wireless charging system, the electromagnetic coupling structure affects the power and efficiency of the system. This article applies the mutual inductance model to study the transmission characteristics of the four compensation networks of the coupling structure. According to the equivalent circuit of the mutual inductance model, the impedance characteristics of the compensation networks are analyzed and the expressions of the compensation capacitance in the primary side are derived. The output power characteristics and efficiency characteristics of the four compensation networks include of SS, SP, PS and PP are further analyzed. And then simulation is conducted to find the relationship between power characteristics and efficiency characteristics with system parameters. Results show that under the same conditions, using the SS compensation network could make the performance of the resonant wireless charging system of electric vehicles better.