1100kV气体绝缘金属封闭开关设备绝缘内部气隙放电缺陷诊断分析与处理

Diagnosis and treatment of air gap discharge defects in insulation of 1100kV GIS equipment

本文分析了一起特高压站1100kV气体绝缘金属封闭开关设备支撑绝缘内部气隙放电缺陷案例。该缺陷由技术人员在特高频局部放电在线监测装置上发现,现场综合运用特高频法、超声波法,结合设备内部结构,对缺陷进行初步分析及定位。在将设备返厂解体检修中,结合脉冲法局部放电试验及3维CT断层扫描技术,对缺陷设备进行综合分析诊断,指出绝缘支撑筒内部气隙是本次局部放电异常的根本原因。结合本次局部放电异常案例分析,对气体绝缘金属封闭开关设备绝缘件生产、质检和运行维护的注意事项及其预防和处理措施提出建议。

In this paper, a partial discharge defect of 1100 kV 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 position ed 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, preventi on and treatment measures for the production, quality inspection and operation of the insulating parts of GIS equipment are put forward.