高压下GIS中异物金属颗粒运动过程的研究

Study on Movement Process of Foreign Metal Particles in GIS at High Voltage

气体绝缘开关设备(gas insulated switchgear,GIS)是将成套的开关设备如断路器、隔离开关、母线等封闭在充以SF_(6)体接地的金属罐体中,而内部异物金属颗粒的存在会引起局部放电甚至绝缘击穿。文中针对高压下GIS中两种典型金属颗粒一线形和球形颗粒的运动特性进行了研究。首先搭建了局部放电试验平台,测试了两种类型金属颗粒放电图谱;其次通过对金属颗粒的受力情况分析数值模拟了不同类型电压下不同类型金属颗粒运动轨迹。数值模拟结果发现在脉冲电压下金属颗粒的运动与其形态存在一定的规律。为进一步后续通过建立金属颗粒在脉冲电压下形态和运动轨迹之间的联系,并进而确定一种图谱打下基础。利用这种图谱,可以对引起GIS故障的金属颗粒进行形状及尺寸的评估。通过文中的研究,为未来进一步确定金属颗粒危害性提供了重要的参考。

Gas insulated switchgear(GIS)encloses a complete set of switchgear such as circuit breakers,disconnec-tor and busbars in a grounded metal enclosure filled with SF_(6)gas.However,the presence of foreign metal particles inside GIS can cause partial discharge and even dielectric breakdown.The movement characteristics of such two typical metal particles as linear and spherical particles in GIS under high voltage are studied.First,a partial discharge test platform is set up the discharge patterns of the two types of metal particles are tested.Then,the trajectories of different types of metal particles under different types of voltages are numerically simulated by the stress analysis of the metal particles.It is found by the numerical simulation results that there is certain law between the movement of the metal particles and its form under impulse voltage.It lays the foundation for setting up the relationship between the form and the trajectory of the metal particles under the impulse voltage and thus identifying a kind of images.The use of this image can perform shape and dimension assessment of the metal particles causing GIS fault.The study in this paper can provide reference for defining further the danger of the metal particles in the future.