The Detection Technology Of Switchgear Partial Discharge Base On Ultrasonic And Transient Earth Voltage

In recent years, the city of the distribution network by the switchgear insulationdegradation characteristics in power accident rising year by year, leading to the distributionnetwork system power supply reliability difference and unstable.This The insulatingproperties degradation caused by partial discharge (PD) is accounting for85%. In view of this,how to effectively find switchgear of partial discharge, timely detection potential insulationfault,has become increasingly concerned problems to be solved on electricity regulatorydepartments, also it is the hot topics of researchers and research institute.Partial discharge is caused from early insulation failure in high and medium pressure,partial discharge behavior will gradually damage the insulating of medium and high voltageswitchgear, and eventually cause the insulation to fail. This study is aimed on the switchgearPD signal.This article first studies the characteristic of switchgear partial discharge, the mechanismof PD and characteristic of all kinds of PD. On the basis of in-depth analysis of the switchgearPD characteristics, two effective switchgear PD detective ways------ultrasonic testing methodand transient of voltage testing method----is introduced. After research the principle ofultrasonic testing, this article proposes the framework of ultrasonic testing system as well asthe method to improve the detection sensitivity. At the same time, after the depth research onthe principle of the discharge detection technology in the transient of voltage and analysis thequestion related to the testing, this article proposed the method of the transient of voltagedischarge detection system framework.Based on the study of ultrasonic and TEV detection of switchgear PD, by participating inmounts of field ultrasonic testing and TEV detection in switchgear in Guangzhou power, andon the analysis of all kinds of interference and various typical cases, this paper puts forwardultrasonic testing and TEV detection of PD signals’ corresponding evaluation standard.