736 / 2022-03-31 20:14:07

Study on harmonic current measurement of power grid based on flexible current Sensor

High-frequency; High order harmonic current of power grid; Flexible current transformer ;Bus

In the power system, the measurement frequency of the traditional current transformer (CT) is mainly for the power frequency, and the high-frequency response characteristic is poor, so the high harmonic current cannot be accurately measured. In order to measure the high order harmonic current of power grid, a method based on flexible current transformer is proposed in this paper. Firstly, a layer of insulating rubber is wrapped on the 10KV bus to provide insulation protection. Secondly, the bus is wrapped with a metal plate with an insulating layer on one side and a metal layer on the other, and the edge of the metal plate is grounded. At this time, as one side of the metal plate is an insulating layer, it cannot form a loop to avoid electromagnetic interference. Finally, the wire trap of the flexible current transformer is used to measure the high harmonic current of the power grid. Experimental results show that this method can measure harmonic current from 50 HZ to 2500HZ, and the accuracy of amplitude is less than 3%.