Directional Characteristics of Wireless Power Transfer via Coupled Magnetic Resonance

Abstract

The wireless power transfer (WPT) system via coupled magnetic resonance (CMR) is an efficient and practical power transmission technology that can realize medium- and long-distance power transmission. People’s requirements for the flexibility of charging equipment are becoming increasingly prominent. How to get rid of the “flitch plate type” wireless charging method and enhance the anti-offset performance is the main research direction. Directional characteristics of the system can affect the load receive power and system efficiency in practical applications. In this paper, the power and efficiency of the WPT system via CMR were analyzed according to the principle of near-field strong coupling at first. The expression of the mutual inductance between the transmitting and the receiving coils under angular offset was derived from the perspective of the mathematical model, and the influences of angular deviation were analyzed. Second, simulation models were established under different distance between coils, different coil types, and different coil radius ratios in symmetrical and asymmetrical systems. Afterwards, the directional law was obtained, providing reference for the optimal design of coupling coils. Finally, an experimental system was built, and directional characteristic experiments were carried out under different conditions. Experimental results were consistent with simulation results, which verified the theoretical analysis.

Near‐field wireless power transfer used in biomedical implants: A comprehensive review

“…However, the separated Tx and Rx coils have selfinductance and are coupled by mutual inductance (M). Rx and Tx can be modeled as two separate series LCR resonators [45,46]. Many other factors should also be considered, including reliability, power consumption, size, feasibility, and patient comfort [36].…”

Analysis of the Magnetic Field Magnetoinductive Wave Characteristics of a Wireless Power Transfer System

“…The stray or leakage magnetic field was analyzed in [17,18] to cancel the stray or leakage magnetic field via different additional coils. The direction of the magnetic field has also been analyzed in [19]. These studies analyzed the magnetic field of a WPT system in the condition of steady state.…”