Analysis of the Frequency Characteristics of MCR‐WPT System with Asymmetric Coils Structure

Abstract

At present, magnetically coupled resonant (MCR) wireless power transfer (WPT) has been widely used in many practical applications. However, the traditional symmetrical coils structure has limited the development of WPT technology, such as the mining and medical field, where the coils structure is always asymmetrical because of their special environment requirements. In the study a novel method was presented for the analysis of the frequency characteristics of the MCR‐WPT system with asymmetric coils structure. The concept of the quality factor ratio of the coils with asymmetrical coils structure was proposed, and then the mathematical relationship between the quality factor ratio and the output power was deduced. In addition, the effects of the quality factor ratio, generalized coupling factor, generalized mismatching factor and frequency splitting factor on the output power and transmission efficiency were studied respectively. The simulation results not only demonstrate the regular pattern between the frequency splitting, the quality factor ratio and the frequency splitting factor, but also validate the condition of the output power achieving the local maximum value. Besides, the results show the relationship between the coupling factor and the transmission efficiency. Finally, an experimental platform was built to verify the theoretical analysis. And the conclusions of the study not only provide theoretical and practical basis for the future study in WPT technology but also can provide beneficial references for the design of WPT system in particular applications. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.