A Universal Mutual Inductance and Load Identification Methodology for MC-WPT Systems with Arbitrary Topology

This paper proposes a universal front-end identification method for mutual inductance and load based on the eigenstate mechanism, which is suitable for magnetic coupling wireless power transfer (MC-WPT) systems with arbitrary topologies. Firstly, the general real eigenstate parameter criterion for arbitrary topology MC-WPT systems is established. Then the general analytical expressions of mutual inductance and load under the real eigenstate are derived. Based on the real eigenstate impedance characteristics, a front-end parameter identification method and process are presented. The proposed method is universally applicable to any topological structure by simply inputting the corresponding impedance parameters. Meanwhile, the constructed mutual inductance and load analytical expressions are decoupled, eliminating the need for iterative processes and concerns about iteration count and convergence precision. This results in fast computation speed and high accuracy. In experiments, the identification accuracy for mutual inductance and load is above 93.95% and 98.22%, respectively. Furthermore, the method does not require any additional identification circuits and combines the advantages of the eigenstate mechanism, such as high energy efficiency and strong anti-offset capability. Additionally, the established general real eigenstate parameter criterion can effectively facilitate the design of parity-time (PT) symmetry mechanisms in systems with various topologies.