Design And Control Strategy Of Two Way Wireless Charging System For Electric Vehicle

In recent years,with the development of global industrialization and informatization,people begin to pay more and more attention to the environmental pollution caused by the burning of traditional fossil fuels.At present,the best way to solve this problem is to reduce the use of fossil energy and vigorously develop new energy.Among them,electric vehicles have attracted extensive attention both at home and abroad due to their low energy consumption,low environmental pollution and so on.With the development of smart grid,especially the introduction of energy Internet,the interactive technology of electric vehicles and power grid has emerged as the times require.Due to a series of inherent defects in the traditional plug-in charging mode,radio energy transmission technology has developed rapidly in recent years.Among them,the magnetic coupling resonant type is widely used in the wireless charging technology of electric vehicles because of its high transmission power and medium transmission distance.Based on this,this paper designs the wireless charging system of electric vehicle which can realize bidirectional energy flow,and studies the corresponding control strategy.In this paper,the basic principle of wireless charging is analyzed and studied,and analyzed the relationship between the electromagnetic induction intensity and the current frequency of the current carrying conductor.Based on mutual inductance coupling model,four commonly used compensation structures are analyzed and studied,and the appropriate compensation method is chosen.Then solved the SS compensation method in detail,and the theoretical formula of the transmission power and deduced transmission efficiency of the topology.A detailed analysis of the second magnetic resonance coupling mechanism in the theoretical basis of the above,combined with simulation by finite element simulation software Maxwell and Simplorer software,the magnetic field distribution of the resonant coil resonant conditions are simulated and analyzed.After the analysis of fault tolerance of this structure in horizontal and vertical direction and angle deviation three,respectively in the horizontal direction of the offset distance and the offset angle of scanning parameters and at different radial distances are simulated.Finally,the circuit part of the two-way wireless charging system for electric vehicles is deeply analyzed and studied.First of all,introduced the core bidirectional DC-DC circuit topology to achieve two-way charging and discharging function,working principle of the fully controlled bridge circuit are analyzed in detail;and the bidirectional energy flow conditions were analyzed,according to different compensation circuit topology structure were deduced the theoretical formula.And the control strategy of the circuit is studied.Two control strategies,phase shift control and frequency conversion control,are developed,and two control strategies are compared through theoretical and simulation experiments.