基于螺线方程的MCR-WPT系统线圈设计

Coil Design for MCR-WPT System Based on Spiral Equation

在磁耦合谐振式无线电能传输MCR-WPT(magnetically-coupled resonant wireless power transfer)系统中,线圈作为能量中转的关键环节,其参数的设计决定了系统的传输效率,但目前仍然没有成熟完善的线圈设计方法。将平面螺旋线圈作为研究对象,采用阿基米德螺线方程,建立了精确的数学模型,分析了耦合线圈互感、自感、电阻与线圈几何参数的关系,得到了较为精确的计算方法。通过COMSOL进行仿真验证,在线圈匝间距较小时,各电量计算误差在5%以内。针对给定的限定条件,以线圈传输效率作为优化目标,通过Matlab求解出最优的线圈参数。最后,绕制实际的线圈并由实验测得其最大传输效率超过95%,证明了线圈设计方法的合理性。

In a magnetically-coupled resonant wireless power transfer(MCR-WPT)system,the coil is the key link of power transfer,and the design of its parameters determines the system’s transfer efficiency.At present,there is still no ma-ture or perfect coil design method.In this paper,a planar spiral coil is taken as the research object,and an exact mathe-matical model is established using the Archimedes spiral equation.The relationship between mutual-inductance,self-inductance,resistance and the geometric parameters of the coupled coil is analyzed,and a more accurate calculation method is obtained.Through the simulations performed using COMSOL,it is verified that when the pitch of the coil is small,the calculation error of each electric parameter is within 5%.For the given restraint conditions,the coil’s transfer efficiency is taken as the optimization target,and the optimal coil parameters are solved using Matlab.Finally,an actual coil was wound,and its maximum transfer efficiency was measured to be higher than 95%,which proves the rationality of the coil design method.