SF_6气体中金属尖端缺陷局部放电发展过程研究

金属尖端缺陷是气体绝缘组合电器(gas insulated switchgear,GIS)设备中易于出现的缺陷类型,通过局部放电检测可以实现对此类缺陷的准确检测。文中针对SF6气体中不同间距的金属尖端缺陷模型,对其在不同外加电压下的发展过程进行了实验研究,利用脉冲电流法对其不同阶段的放电谱图进行了测量,结果表明,不同间距下局部放电的发展特征具有区别,间距很小时,发展阶段仅有2个,而在间距较大的情况下,发展阶段则可划分为4个。在施加电压接近击穿电压时,放电谱图都表现出了单个半周的双峰特点。研究结果为GIS设备局部放电检测结果的分析及状态评估提供了基础。

Study on the PD Development Process of Metallic Protrusion in SF_6 Gas

Metallic protrusion defects are types of defects that are easy to occur in gas insulated switchgear(GIS)equipment.Accurate detection of such defects can be achieved by partial discharge detection.This paper is aimed atmetallic protrusion defect models with different distance in SF6 gas.The experimental research on the developmentprocess under different applied voltages was carried out.The discharge pattern of different stages were measured bypulse current method.The results show that the development characteristics of partial discharges at different distanceare different. For the small distance,there are only two development stage,and for the long distance,the developmentprocess can be divided into four.When the applied voltage is close to the breakdown voltage,the discharge patternshows a double-peak characteristic of a single half cycle.The research results provide a basis for the analysis and state evaluation of the partial discharge test results of GIS equipment.