Research on online energy extraction device for high-voltage line

The safe operation of high voltage transmission lines is an important part of smart grid. However, the power supply problem of online monitoring equipment is a technical difficulty. In this paper, the design principle of the online energy acquisition device is sorted out. Firstly, the energy coil induces energy from the magnetic field near the high-voltage AC transmission cable, and then charges the supercapacitor through the instantaneous overvoltage protection module and the rectifier filter module. The supercapacitor outputs a stable DC signal through the voltage regulator module. In order to better configure the parameters, the output power of the coil is theoretically deduced, and the characteristics of the coil output are studied in different aspects such as the material of the magnetic core, the maximum output power point of the coil, and whether there is an air gap in the coil. Finally, the reason of coil saturation is explained, and the coil saturation is limited by limiting the size of the coil excitation current. The research results of this paper can provide reference for the design of online energy acquisition device for high voltage transmission lines.