电动汽车无线充电优化设计

Optimal Design ofWireless Charging for Electric Vehicles

目前,电动汽车生产厂家众多,而无线充电又没有统一标准,造成了充电效率低下的问题。为解决此问题,尝试通过对无线充电的发射频率、匹配阻抗及耦合系数进行优化,建立基于发射频率、匹配阻抗、两线圈距离与无线电能传输效率的数学模型,得出考虑无线充电车载部分与地面距离因素下的充电效率。另外,还考虑线圈偏移引起的耦合互感降低而导致传递效率降低的问题,利用有限元软件进行仿真,为无线充电中的耦合互感在不同距离、不同频率、不同偏移系数间的能量传递效率提供一定的理论指导;对当前电动汽车互感线圈间的磁耦合研究做出了一定的拓展和创新,使得无线充电设备与不同生产厂家的电动汽车之间互联互通。

At present,a large number of electric vehicle manufacturers do not have a unified wireless charging standard,resulting in low charging efficiency.To solve this problem,this paper establishes a mathematical model based on the emission frequency,matching impedance,distance between two coils and radio energy transmission efficiency by optimizing the emission frequency,matching impedance and coupling coefficient of the non-vehicle-mounted part of wireless charging,and then obtains the charging efficiency considering the distance between vehicle-mounted part of wireless charging and the ground.Furthermore,the reduction of coupling mutual inductance caused by coil offset is considered,which leads to the reduction of transfer efficiency.Finite element software is applied to simulate and analyze the change rule of coupling mutual inductance with offset,so that wireless charging equipment can be interconnected with electric vehicles from different manufacturers.