This paper designs a multiple relay wireless power transmission (WPT) system with a 3-coil coupling structure, which can be used in 110kV composite insulators. Through theoretical derivation, the circuit model of multiple relay WPT system and the characteristics of output voltage and current are obtained The proposed three-dimensional coil structure can save the weight and volume of the magnetic core, and has a high coupling coefficient in the case of long air gaps. Through finite element simulation analysis, it is shown that the embedding of the system does not affect the electric field distribution of the composite insulator, and has no significant impact on the insulation performance of the composite insulator. An experimental platform with a wireless energy transmission distance of 1.5m is built, and the output characteristics of the system are verified. Under 10V DC input, the output power reaches 4.14W, with a maximum efficiency of 28.37%.

Multi-relay, wireless power transmission, magnetic core dissect