A Review on Insulation Failure and Partial Discharge in Gas Insulation Switchgear Considering Protrusion, Void and Free Particle

Today, the role of electric energy in creating social welfare and industrial development of human societies is not hidden from anyone. In recent years, comprehensive and complete laws have been compiled and implemented for the production and supply of this energy in the market. What shows up more than ever is the concern of engineers in this field for the production, transmission and uninterrupted supply of electrical energy. The use of efficient equipment with high reliability has led engineers to use gas insulated posts in transmission and distribution networks. The use of gas insulation, while reducing the dimensions, has caused a reduction in transportation costs and installation and commissioning time of this equipment. Although gas insulation equipment requires minimal repairs due to special manufacturing technology and insulation, but the reliability and proper functioning decreases as the life of this equipment increases. Often over time, partial drainage is a defect that occurs in this equipment. This event leads to insulation failure finally, which is an important quantity in assessing insulation conditions. The most common causes of partial discharge in gas substations are three factors: conductor electrode protrusion, Existence of void in insulation and free particles suspended in gas pressurized enclosure. In this paper, studies related to the factors affecting the insulation failure of GIS substations and its timely detection methods, based on the benefit of existing articles and research.