Simulation And Application Research On Partial Discharge Characteristics Of Air Gap In Power Equipment Of Transformer Substation

With the development of power system,safe and reliable electrical equipment plays an important role in the power system.For a long time,insulation problem is the weak link of power equipment,and the electrical equipment inevitably will appear partial discharge and insulation damage.Therefore,the detection of electrical equipment online is very important.In addition to the routine preventive test,it should also develop live detection technology,which can detect the insulation state and defect types of high-voltage electrical equipment,so as to detect possible abnormalities or fault precursors and process them in time.Therefore,it is of great significance to research on partial discharge of air gaps in power equipment.This paper analyzes the mechanism and process of partial discharge,summarizes the types and characteristics of partial discharge,and explores the factors affecting partial discharge.What’s more,for the classical air-gap discharge model,the parameters that can represent the partial discharge are analyzed.Besides,according to the distributed circuit simulation model of single air gap partial discharge,the different air gap discharge paths,the different processes and electronic avalanche process of the air gap discharge are simulated.The equivalent circuit simulating models of air gap partial discharge in high voltage switchgear are established by using Matlab/simulink.The specific control method of numerical simulation of different breakdown processes of air gap is studied.At the same time,considering the influence of space charge and residual voltage on the simulation process of air gap discharge,an improved equivalent circuit model of air gap discharge by introducing controlled current source is established and simulated.Combined with the conclusion of simulation analysis,the actual live detection cases and the monitoring data of a large number of outsourcing teams are analyzed and discussed,which shows that the characteristics and Simulation of partial discharge can be used to analyze the phenomenon of partial discharge in power production practice.