A Misalignment Adaptive WPT System Ensuring Maximum Power Transfer under Asymmetric Frequency Splitting Conditions

Abstract

One of the major issues is that the output power and power transfer efficiency are dependent on the coupling coefficient (k) between the magnetic couplers. Any deviations in optimal distance, misalignment between the couplers or unmodeled dynamics such as temperature dependent variation in components lead to a shift in system's resonance frequency. Also, asymmetric frequency splitting phenomenon occurs decreasing the output power and the power transfer efficiency of the system. Non-metaheuristic optimization methods are not capable of distinguishing the global maximum power (GMP) transfer frequency under frequency splitting conditions. This study presents an adaptive wireless power transfer (WPT) system with a Cuckoo Search Algorithm (CSA) based frequency-tracking method. GMP transfer frequencies determined by experimental frequency scanning method. The method is implemented under asymmetric splitting conditions for the first time. The suitability of the algorithm is tested in an experimental WPT setup. In experimental studies, wireless power transfer was provided through flux pipe couplers with three sub-coils which exhibit higher coupling coefficient as compared to traditional flux pipe couplers with two sub-coils. Results show that the CSA based controller can accurately find the optimal operation frequency under various misalignment and distance between the couplers.