Gas insulated switchgear (GIS) partial discharge calibration method and system

Abstract

The invention discloses a gas insulated switchgear (GIS) partial discharge calibration method and a system. The method comprises the steps of establishing a calibration data set, and calibrating a preset position of data in the data set in a GIS; measuring an actual waveform oscillation rising time and an actual maximum amplitude of GIS actual partial discharge on the preset position; comparing the actual waveform oscillating rising time and the actual maximum amplitude with the data in the calibration data set, and carrying out calculation, so as to acquire a discharge part and strength. Specifically, the calibration method disclosed by the invention can accurately measure the calibration data set and data of actual partial discharge through a sensor on the preset position, so that defects of arranging two sensors on each GIS interval and serious error of reading head wave initial time are avoided; in later stage, the discharge part and strength are obtained by simple comparison and calculation, which is free from limitation of an atlas database and overcomes shortcomings of the existing ultra high frequency (UHF) method that pattern recognition fails to accurately provide the discharge strength. Therefore, the calibration method disclosed by the invention can accurately and effectively detects discharge part and strength of partial discharge.

Description

technical field [0001] The invention belongs to the technical field of partial discharge detection and maintenance in electric power systems, and in particular relates to a GIS (Gas Insulated Switchgear, gas insulated switchgear) partial discharge verification method and system. Background technique [0002] Due to the advantages of small footprint, high operational reliability, small maintenance workload, and no electromagnetic interference, GIS has been widely used in my country's power system since the 1980s. With the increase of the number of GIS applications, there are more and more GIS security accidents, which have caused huge losses to the national economy. Among them, insulation defect is one of the important factors affecting the reliability of GIS. When there is insulation defect inside GIS, partial discharge will be generated under the action of high voltage. Therefore, partial discharge is an important symptom of insulation defect. If the internal insulation de...

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Problems solved by technology

[0004] However, the above-mentioned UHF-based partial discharge discharge location and discharge intensity detection method has the following problems: (1) At present, since only one UHF sensor is configured on each GIS interval, although people have proposed a time difference method, in most cases However, this method cannot be put into practical use; (2) Due to the small peak value of the first wave of the UHF signal and the complex background noise on site, the reading error at the initial moment of the first wave is very large, which in turn leads to great problems in the location of the discharge site. (3) Since the spectral library obtained in the laboratory cannot contain all defects, and thus affected by the limitations of the spectral library and on-site interference, the pattern recognition method cannot accurately determine the type and stage of partial discharge, nor can it accurately give Discharge intensity of UHF electromagnetic wave signal at the discharge source

In summary, the existing UHF-based detection methods cannot accurately and effectively detect the discharge location and discharge intensity of partial discharge in GIS

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