电动汽车无线充电系统金属异物检测灵敏度优化方法

Sensitivity Optimization Method for Metal Object Detection in Electric Vehicle Wireless Charging System

为提高电动汽车无线充电系统金属异物检测性能,提出1种检测线圈灵敏度优化方法。首先,建立金属异物介入矩形检测线圈的等效电磁模型,研究线圈的物理参数变化机理,得到不同尺寸金属异物引起的检测线圈参数变化理论公式;其次,分析多个线圈构型参数对检测线圈灵敏度的影响,结合无线充电实际工况优化检测线圈构型,通过电磁场仿真及实验证明了理论模型的准确性;最后,在3 kW无线充电系统中进行金属异物检测实验,结果表明:以优化后检测线圈为基础搭建的金属异物检测系统可以准确地检测到25 mm及以上尺寸的金属异物,并具有抗干扰能力。

To improve the metal object detection performance for an electric vehicle wireless charging system,a sensitivity optimization method for the detection coil was proposed.The equivalent electromagnetic model of a rectangular detection coil with a metal object approaching was established.The changing mechanism of the physical parameters of the coil was studied,and a theoretical formula for changes in the parameters of the detection coil which were caused by metal objects of different sizes was obtained.The influence of several configuration parameters on the sensitivity of the detection coil was analyzed,and the configuration of the detection coil was optimized by combining the actual operating conditions of wireless charging.Through the electromagnetic field simulation and experimental verification,the accuracy of the theoretical model was proved.Finally,a metal object detection experiment was carried out in a 3 kW wireless charging system,which verified that the metal object detection system built on the basis of the optimized detection coil can detect metal objects with a size of 25 mm and above.In addition,it had anti-interference capability.