Analysis and Design of Discrete Ferrite Rings to Improve the Efficiency of Meter-Range Wireless Gap Inductive Power Transfer System

In this article, discrete Ferrite rings (DFRs) applied to cylindrical solenoid coupler (CSC) is proposed. The coupling coefficient between adjacent coils is enhanced and the inductance of the coils is increased by reducing the reluctance in the magnetic circuit. The DFRs-based CSCs magnetic structure is considered to be applied for post insulators. The inductive power transfer (IPT) system based on the abovementioned magnetic structure is used to power the state detection equipment at high potential points. A finite element simulation analysis of the electric field is finished to verify that the addition of DFRs does not affect the insulation properties of the post insulator. The parameters of DFRs are optimized to improve their effect on coupling coefficient and self-inductance based on the finite element method. The multilayer coils and the decoupling series compensation method are analyzed. The circuit model of the three-stage IPT system is built and analyzed. A 1.54 m long-range IPT system prototype is completed to simulate the 110 kV post insulator. A series of experiments are performed to verify the advantages of the proposed DFRs. Efficiency of the meter-range IPT system can reach 75.4%.