Analysis of the Electromagnetic Coupling Characteristics of Dual-Load Wireless Power Transmission Channels

Abstract

This paper studies the characteristics of four dual-load systems, coaxial different sides, coaxial same side, different axis same side, and coplanar coaxial, based on the principle of near-field resonance wireless power transmission. Firstly, a dual-load cooperative coupling equivalent circuit model is established, the mathematical expression of system energy efficiency is derived, and the influence of the cross-coupling of the receiving coils in the system on the performance of the system is compared and analyzed in four coupling situations. Secondly, the magnetic field distribution characteristics and the influence of transmission distance and load impedance on the transmission characteristics are studied by electromagnetic field simulation software. Finally, the experimental results show that the maximum efficiency of the dual-load wireless power transmission system is only 0.43 in the case of coaxial and coplanar coupling, which is not suitable for power transmission. In the case of coaxial coupling on the same side, the received power of dual loads has a large difference, which is suitable for electrical equipment with different power requirements. When the coupling distance between the transmitting and receiving coils changes synchronously in the case of coaxial opposite-side and different axis same-side coupling, the efficiency of the former persisting declination and the efficiency of the latter rise first and then drop.