Cause Analysis of Abnormal Condition in Partial Discharge Test of 220kV GIS

Abstract

With the continuous development and construction of the power grid system, 220kV GIS equipment has been widely used in ultra-high voltage substations. Before leaving the factory, GIS equipment needs to be tested for lightning impact, partial discharge, etc. to check whether there are problems in the manufacturing, assembly and other links of the equipment. This paper analyzes a 220kV GIS when the partial discharge test (factory test) occurs when the partial discharge exceeds the standard. By using the directional elimination method, the equipment fault range is determined, and the fault structure is disassembled. Analysis, X-ray flaw detection results found that the insulation There are tiny bubbles in the base, indicating that the assembly workshop has problems of technical control or lack of cleanliness. At the same time, after the insulation base has been subjected to multiple lightning strikes, due to the cumulative effect, the equipment has exceeded the standard in the partial discharge test. Finally, through the analysis of the cause of the failure, the targeted rectification measures are put forward to improve the technical management and control level of the assembly workshop.