Automatic Impedance Matching Method with Adaptive Network Based Fuzzy Inference System for WPT

In a wireless power transfer system via coupled magnetic resonance, the power transfer efficiency (PTE) drastically decreases with the transfer distance and the changing load. To solve this problem, an automatic impedance matching system is usually embedded in an intelligent algorithm. However, the traditional algorithm cannot dynamically track the impedance due to its slow matching speed. In this paper, an automatic impedance matching method based on adaptive network based fuzzy inference system (ANFIS) is proposed to overcome this disadvantage. A simulation system is constructed, and results show that the efficiency of the proposed ANFIS method is 80.26% higher than that of the genetic algorithm. Moreover, an automatic impedance matching prototype is built and dynamic matching experiments are carried out, showing that the PTE is up to 84.76% when the distance increases from 4.5 to 50 cm. The simulation and experimental results are basically consistent, which prove the validity of the novel method.