基于正四面体的无线电能传输系统多自由度电能拾取机构

Multi-degree-of-freedom Pick-up Mechanism of Wireless Power Transfer Systems Based on the Regular Tetrahedron

传统无线电能传输系统对拾取结构的方向性较为敏感,拾取机构角度变化将会较大地影响系统功率传输特性。针对无线电能传输系统三维空间内多自由度拾取问题,该文提出一种基于正四面体的电能拾取机构,给出拾取电感摆放位置及连接方式,完成拾取机构磁通分析,提出拾取机构在空间内旋转时不同绕线方式的互感计算方法,设计拾取线圈的最优绕线方案,通过Maxwell有限元仿真获得拾取线圈间的相互耦合关系。实验结果表明:当耦合机构以任意角度旋转时,系统多自由度运行的效率维持在60%,负载功率维持在30W。此种类型的拾取机构不仅能提升系统的多自由度拾取能力,还可以保持输出的稳定性,减小系统对输出控制环节的依赖,减小拾取装置体积。

The traditional Wireless Power Transfer（WPT） system is sensitive to the directivity of pickup structure. The pickup angle will greatly affect the system power transmission characteristics. To solve the problems existing in the conventional wireless power transfer system for multi-angle power pickup in a three-dimensional space, a novel pick-up mechanism based on the regular tetrahedron was put forward. The placement and connection of pickup inductances were introduced. Through analyzing the magnetic flux of pick-up mechanism, the mutual inductance calculation methods of different winding schemes for rotating pickup mechanism was proposed, and the optimal winding scheme of the pickup mechanism was designed. Through Maxwell finite element simulation, the mutual coupling relationship between pickup coils were obtained. The experimental results show that the system efficiency is maintained at 60%, and the load power is maintained at 30 W when the pickup mechanism working at an arbitrary angle of rotation. This structure of pickup mechanism can not only enhance the ability of multi-degree-of-freedom power pickup, it can also maintain the stability of the output, reduce the dependence on the output control link and reduce the pickup volume as well.