Modeling And Optimization Of Launching Rail For Electric Vehicle Dynamic Charging System

Since the global environmental problems have become more and more serious,the development of the new energy technology industry has been put on the agenda early,and in the automotive industry,countries have set a timetable for the suspension of fuel vehicles.The research on electric vehicles has attracted much attention.Because electric vehicles use traditional wire connection charging,there are problems such as long charging time,cumbersome charging methods,safety hazards in rain and snow,and damage to the charging head.Experts and scholars have proposed to use wireless power transfer to charge electric vehicles,which proposes a new solution for electric vehicle charging.The use of MC-WPT technology to charge electric vehicles has become the preferred solution.In the electric vehicle charging system,the design of electromagnetic coupling mechanism is extremely critical,which is related to the transmission power and transmission efficiency of the whole system.However,the research on the electromagnetic coupling mechanism of the MC-WPT system at home and abroad shows that the launching rail is more advantageous with the short rail cascading.The electric vehicle dynamic charging system with the traditional circular structure and rectangular structure as the launching rail exists dropping of pick up power during the rail cutover process.Based on this phenomenon,this paper studies the electromagnetic characteristics of the corresponding launching rails under the cutover state of the rails,and theoretically models and deduces the magnetic field strength and the primary and secondary side equivalent mutual inductance of the switching domain under the two structures.In turn,relevant factors affecting the reduction of the coupling ability of the electromagnetic coupling mechanism in the cutover domain are obtained.Aiming at the related factors affecting the coupling performance of the coupling coil under the switching domain,this paper proposes a new type of launching rail structure.Based on the electromagnetic field simulation software,the characteristics of the rail structure are analyzed.The simulation shows that the equivalent mutual inductance is smooth during the rail switching domain when using the new type rail strycture.Then the experimental device is built to test the validity of the structure.The final experimental results are consistent with the simulation,which verifies the validity of the rail structure in this paper.