Research And Application Of Superhigh Frequency Signal Detection Technology

Insulation damage of high voltage power equipment caused by aging and production defects is one of the main reasons for equipment outage and electrical accidents.At present,among the methods of makong insulation defect detection and evaluation for substation power equipment,using partial discharge instrument to test the partial discharge of equipment is the most simple and effective one.The principle is to input short-term excitation to the equipment,observe and analyze the partial discharge characteristics of each part,and complete the assessment of fault location and fault nature.Due to the complexity of the substation system and the existence of various electromagnetic interference in the signal,the reasonable extraction and analysis of partial discharge signal is an important part of fault detection and fault location,which directly determines the detection effect of partial discharge.SHF is the main component of electromagnetic wave signal excited by partial discharge Frequency)band signal is extracted and analyzed accurately,and then fault diagnosis and fault location of primary main equipment such as main transformer and GIS are completed to ensure power supply safety and power supply reliability of power system.This paper studies the mechanism of SHF signal generation in the process of partial discharge,the partial discharge detection method based on SHF signal,and designs a partial discharge detection system scheme based on SHF,which provides technical support for rapid and efficient partial discharge detection.Further more,the research results can be used for live partial discharge detection of substation equipment with different voltage levels and on-line monitoring of partial discharge,improve the reliability and stability of equipment partial discharge detection,reduce operation and maintenance costs,and achieve obvious economic benefits.The main research contents and results of this paper are as follows:（1）In this paper,the particle in cell Monte Carlo model（PIC-MCC model）is used to simulate and analyze the typical partial discharge principle and SHF signal generation mechanism.The bus outgoing line area of the three-dimensional model of 500 kV actual substation is selected as the simulation environment to study the time-domain characteristics of electromagnetic wave,which points out the direction for the development of partial discharge detection system based on SHF.（2）In this paper,a set of typical partial discharge model and test platform are designed and manufactured,and the built test platform is used to detect the ultra-high frequency components of on-site partial discharge signals,verify the existence of SHF band signals in the process of partial discharge,and further verify the feasibility of this project.