1. State Grid Jiangsu Electric Power Co., Ltd, Overhaul Company, Nanjing 210000; 2. Electric Power Research Institute of State Grid Jiangsu Electric Power Co., Ltd, Nanjing 210000
Abstract:In this paper, a partial discharge defect of 1100kV GIS in UHV station is analyzed. The defect is found by UHF partial discharge on-line monitoring device. UHF method and ultrasonic method are synthetically used in site, and the defect is preliminarily analyzed and positioned in combination with the internal structure of the equipment. In the process of dismantling and repairing the equipment when it returns to the factory, combined with pulse partial discharge test and 3-D CT tomography technology, the defective equipment is analyzed and diagnosed in the factory. It is pointed out that the air gap in the insulating support barrel is the fundamental cause of the abnormal partial discharge. Based on the case analysis of the abnormal partial discharge, the precautions, prevention and treatment measures for the production, quality inspection and operation of the insulating parts of GIS equipment are put forward.