Research And Design Of Electric Vehicle Wireless Power Transfer System Circuit

With the human pursuit of green energy,electric vehicles have gradually entered people's lives,but this has also brought about charging problems.At present,electric vehicles are mainly charged by wired means.With the development of power electronics technology,wireless power transfer technology has attracted people's attention.If wireless charging technology is applied to electric vehicles,it can make the use of electric vehicles more convenient and safer.In this article,the circuit part of the wireless power transmission system of electric vehicles is studied,and then the parameters of the system are designed based on theory.The main research contents and result are as follows:(1)This article investigates the current research status of wireless charging technology for electric vehicles,analyzes the needs of wireless charging for electric vehicles,and summarizes the research results on circuit modeling and analysis of wireless power transfer.(2)Based on the inductive wireless power transfer technology,this article analyzes the circuit model of the coupled coil,and studies the parameter changes of the coil under different conditions.The basic characteristics of the basic resonance compensation circuit and the double-sided LCC resonance compensation are derived,and the characteristics of the input pure resistance and output constant current of the double-sided LCC circuit are studied in detail.The advantages and disadvantages of the basic resonance compensation circuit and the double-sided LCC circuit are compared,and it is concluded that the double-sided LCC circuit is more suitable for wireless charging of electric vehicles.(3)Analyze the phase shift control method of the high-frequency inverter,analyze and study the soft-switching state of the high-frequency inverter with double-sided LCC circuits,and propose a method to judge the soft-switching of the inverter.The approximate relationship between the input and output of the rectifier is analyzed.(4)The parameters of the double-sided LCC circuit are designed based on theoretical analysis.A method of adjusting the input impedance of the double-sided LCC circuit is proposed,which can make the input impedance of the resonance compensation circuit appear inductive without breaking the excellent characteristics of the double-sided LCC circuit.Help the inverter to realize soft switching,the validity of the design parameters are verified through simulation results.A constant-current and constant-voltage dual-closed-loop control scheme suitable for wireless charging of electric vehicles is proposed to realize constant-current and constant-voltage charging of battery packs.(5)A simulation model of the system was constructed,a high-frequency inverter and a rectifier including a controller and Bluetooth wireless communication were designed,and a set of experimental platform for electric vehicle wireless charging system with a maximum power of 6 kW was set up,and simulated charging The test and experimental results show that the highest efficiency reaches 92.3%.