Study On Design Of Electric Vehicle Wireless Charging System And Voltage Stabilization Control Under Mutual Inductive Disturbance

Under the background of increasingly exhausted energy and serious smog pollution,electric vehicles have gradually become the first choice for car buyers,regardless of their consideration for healthy living or the encouragement of national policies.With the expansion of market demand,the key technologies of electric vehicles have become research hotspots in various fields.In the field of electric vehicle charging,Wireless Power Transmission(WPT)technology is gradually gaining widespread attention and research with its intelligent control,no manual operation and danger of electric shock.The power transmission medium of WPT technology mainly includes electric field,magnetic field,microwave,etc.,and the inductively coupled power transfer(ICPT)technology using magnetic field as mediumis is gradually being fully researched and applied in the field of wireless charging of electric vehicles because of its low working frequency,low electromagnetic radiation,more easily shielded and the ability to achieve greater power transmission.At present,in the field of wireless charging of electric vehicles,ICPT technology mainly focuses on static constant voltage or constant current wireless charging technology of electric vehicles.The electric vehicle wireless charging system based on ICPT technology is complicated in composition,and small parameter changes will affect its output characteristics.When the electric vehicle is wirelessly charged,it will inevitably be affected by the actual site flatness and the parking angle.The small-range perturbation of the mutual inductance coupling coefficient in the ICPT system affects the constant voltage or constant current output of the electric vehicle wireless charging system.Therefore,based on the design of electric vehicle wireless charging system based on ICPT technology,based on the traditional frequency domain method,the design of the constant voltage output closed-loop controller of electric vehicle wireless charging system is completed to meet system's constant voltage output characteristics under the mutual inductance coupling coefficient disturbance.In view of the above analysis,firstly,this paper studies and analyzes the research background of electric vehicle ICPT technology,ICPT system modeling and control methods at home and abroad.Secondly,taking the composition of electric vehicle wireless charging system as the starting point,the paper completes the theoretical summary of its components—electric energy conversion unit,resonance compensation network and magnetic circuit coupling mechanism.Then,based on the theoretical analysis,the design of the 3.3kW electric vehicle wireless charging system is completed,which mainly includes the topology selection,parameter design and period selection of each component of the system.Then,in order to realize the constant voltage output of the electric vehicle wireless charging system under the mutual inductance coupling coefficient disturbance,the modeling and analysis of the 3.3kW electric vehicle wireless charging system is completed based on the circuit average method and the generalized state space average model method(GSSA),and design of system constant voltage controller and current sharing constant voltage controller by frequency domain method.Then,for the system hardware circuit,the voltage and current sampling circuit,the MOSFET drive circuit and the controller discretization and the analysis and design of the system software are completed.Finally,the theoretical analysis and the validity and correctness of the controller are verified by constructing the simulation and experimental platform.