Research On Dynamic Wireless Charging System Of Electric Vehicles Based On Dual Receivers

With the increasing global environmental pollution,the development and application of green transportation such as electric vehicles has become more and more important.Electric vehicles have many advantages such as low pollution,low maintenance and driving costs.However,electric vehicles have the problems of short endurance mileage and frequent charging.Dynamic wireless charging technology can supply electric energy for electric vehicles in the process of moving,has broad application prospects.This paper studies the dynamic wireless charging system of electric vehicles based on dual receivers.Aiming at the influence of cross mutual inductance between adjacent coils on the system characteristics,the loss caused by the transmitting coil current,and the coil switching problem,research is carried out from the aspects of the system's power supply structure,the compen-sation network and magnetic coupling mechanism.The basic characteristics of the LCC-S resonance compensation network are analyzed.Through reasonable parameter configuration,the transmitting coil current can have the characteristics of a constant current source without being affected by mutual inductance and load changes.The Maxwell electromagnetic simulation software was used to compare and analyze the coil model of the magnetic coupling mechanism and the anti-offset characteristics at different distances between adjacent transmitting coils.It was found that when the distance between adjacent transmitting coils was small,due to the complementary relationship of the coupling coefficients,with good anti-offset characteristics,the output power fluctuation is small.In order to eliminate the influence of the cross mutual inductance between adjacent coils on the system characteristics,the compensation capacitor was optimized and designed.Theoretical analysis,simulation and experiments verified that the compensation capacitor optimization scheme can effectively improve the output power and efficiency of the system.Experimental results shown that after the compensation capacitor is optimized,the output power of the system is increased by 41.3%,the efficiency is increased by 8.8%,and the system is working in a resonance state.Aiming at the loss caused by the transmitting coil current and the coil switching problem,a current detection auxiliary circuit based on LCC compensation is proposed.The theoretical analysis and simulation verify that the auxiliary circuit can effectively reduce the system loss and achieve reliable coil switching.Simulation results show that the more number of transmitting coils,the greater effect of the auxiliary circuit on reducing system losses.