Effect of asymmetric coils with non-parallel coaxial on the transfer efficiency of MCR-WPT

As a new power transfer mode,wireless power transfer(WPT) via coupled magnetic resonances brings great convenience to the industrial,medical and life field. However,the traditional symmetrical coil structure has limited the applications of WPT technology in the fields with special needs,such as the field of the mine and medical. Based on the WPT system with asymmetric coil structure proposed by predecessors,the paper analyzed the effect of the ratio of transfer distance to radius,the ratio of the radius of the two coils and angular misalignment of the non-parallel coaxial coils on the transfer efficiency of WPT via coupled magnetic resonance and the mutual effect on efficiency among each factors. Simulation results shows that,the larger the ratio of the transfer distance to radius is,the smaller the range of the angular misalignment will be. And the effect of angular misalignment on the transfer efficiency is more gentle. With the increase of the ratio of transfer distance to radius,the efficiency increases first and then decreases,and when the angular misalignment is around 80°,the effect is the greatest. And the effect of the ratio of the radius of the two coils on transfer efficiency is related to the angular misalignment and transfer distance. The experiment results show that the theoretical analysis of the paper is correct,which providing an useful theoretical reference for the design and further re- search on the WPT system in complicated environment.