Transmission characteristics of magnetic resonance coupling-based multi-load wireless power transmission system

Abstract

If the magnetic resonance coupling-based wireless power transmission system has multiple receivers, cross-coupling will occur between the transmitter and the receiver, resulting in the variation of transmission characteristics when compared with the case of a single receiver. To solve this problem, a mutual inductance coupling circuit model for double-relay and multi-load transmission system and a calculation model for mutual inductance between solenoid coils in the same plane have been built to study the transmission characteristics of the system through simulation and testing. The study results show that: the cross-coupling effect between the transmitter and the receiver will cause resonance frequency shift, or even lead to the variation of resonance frequency splitting characteristic; when compared with a single-load system, the multi-load system may increase in total transmission power and efficiency; generally, with the introduction of additional receivers, the receiving power and efficiency of the original loads will decrease; along with the increase in circuit spacing and the decrease in cross-coupling, the transmission characteristics will gradually regress to the state of a single-load system. In this article, the calculation model for mutual inductance is correct and the maximum relative error in these calculating examples is 5.28%.

Keywords

• inductive power transmission
• coupled circuits
• magnetic resonance
• solenoids
• transmission characteristics
• multiple receivers
• single receiver
• mutual inductance coupling circuit model
• double-relay
• cross-coupling effect
• resonance frequency shift
• resonance frequency splitting characteristic
• single-load system
• wireless power transmission system
• transmission power efficiency
• transmission channel
• magnetic resonance coupling-based multiload WPT system