Electric Vehicles Wireless Charging System Compensation Research Based On The Magnetic Energy Recovery Switch

With the electric car industry chains springing up, wireless charging technology has been winning more and more people’s concern. For electric vehicles, wireless power transmission not only reflects on its economy, safety and convenience, but more importantly, the technology will be being an important part of the process of auto intelligent and a part of the future cars.However, in a real wireless charging scenario, when a different kind of electric cars qre parking on the charging coil, the corresponding equivalent loads value are different, even the same car, along with the increasing period of service, the equivalent load has also being changed. Aiming at these problems and the insufficiency, basing on the magnetic energy recovery switch(MERS) as the research object, on the premise of choosing a series- series compensation topology, and using the double closed loop control(the maximum efficiency- the optimal load), the load of the system can be realized the optimum load matching.Firstly, this article elaborates the background and significance of wireless charging technology, and makes comparison on the situation of technology types and the technology status, and analyses major existing problems, then aims at the load and frequency double matching problem, which put forward the research content.Secondly, based on the magnetic energy recovery switch compensation, the paper remodels electric vehicle charging system, analyzes the MERS circuit structure, working principles and control parameters, and expounds the corresponding mathematical model of different control parameters. Comparing and analyzing the four basic compensation topologies, mathematically proved the series- series resonance compensation is more suitable for high power transmission, then deducing optimal load of system the corresponding maximum efficiency. The MERS circuit is being introduced into the final series-series resonance compensation topology.Thirdly, in the process of the design of the control system, the paper adopts the phase shifting control to design a whole bridge inverter; after the inverter, and connects inseries the MERS in the series compensation topology. To the phase detection of distort voltage and current, this paper proposes a phase-locked loop control algorithm; Analyze and compare the similarities and differences between maximum efficiency transmission and maximum power transfer, and in view of the maximum transmission efficiency, and then introduced in a double closed loop control strategy which is the maximum efficiency outer loop, the optimal load the inner loop.Fourthly, using the software MATLAB and PSIM, on the above mathematical models and control system analyzed in the simulation, verifies the feasibility of the proposed topology and control scheme.Fifthly, Design a 200 W experimental prototype, through debugging and running to verify its load matching and efficiency performance.At the end, from the above, work of the study is summarized and concluded. What’s more, the future work is also presented at the end of the paper.