基于双螺旋正交线圈的强抗偏移IPT系统

A High Misalignment Tolerant Inductive Power Transfer System Based on Double-solenoid Quadrature Pad

为解决传统单拾取感应电能传输系统在横向大偏位下输出电压和系统效率骤降的问题,文中提出由方形正交子线圈与双螺旋子线圈组成的双螺旋正交线圈(double-solenoid quadrature pad,DSQP),该线圈结构与钳位电路相结合,可实现两种线圈之间自动切换,保证系统输出电压在较大的横向偏移范围内波动较小且效率较高。该方法无需原副边通讯,通过后级Buck实现输出电压的精准控制。文中解释DSQP偏移过程中如何利用纵向和横向磁通的变化实现强抗偏移性,同时给出利用有限元软件优化设计耦合机构的方法。最后搭建500W恒功率输出的实验样机验证所提出方法的正确性。原副边尺寸都为400mm×400mm,在X方向偏移±320mm(80%)范围内,等效互感波动仅为15%,输出电压一直稳定在72V,系统包括Buck变换器在内的直流到直流效率为87.4%~90.5%。

The traditional single-receiver inductive power transfer(IPT)system has a sharp drop in output voltage and system efficiency under significant misalignment.To solve this problem,the double-solenoid quadrature pad(DSQP),consisting of a square quadrature coil and the double-solenoid coil,was proposed.The coil structure was combined with the clamp circuit to realize automatic switching between the two coils and stable output capacity with relatively high efficiency versus the large misalignment range.A buck converter was employed to precisely control output voltage without RF communication.The misalignment performance and the design method of the proposed DSQP were elaborated.Finally,a 500W prototype was constructed to verify the validity of the proposed method.The outer dimension of both the primary and the secondary side coils were 400mm×400mm.The experimental results show that the dc output voltage can be maintained at 72V with 320mm(80%)misalignment.The DC-DC(including Buck)system efficiency is at least 87.4%,and the highest is 90.5%.