高压组合电器开关放电声压仿真分析

Simulation analysis of discharge sound pressure of high voltage combinator switch

针对气体绝缘金属封闭开关设备(gas insulated switchgear,GIS)发生局放时形成复杂的声场效应不便対实物分析问题,对该声场建立流固耦合分析模型,使用有限元分析法对GIS内部声源与中心导电杆及外部腔室产生的耦合作用进行计算,实现对GIS设备金属筒壁的声压分布及传播特点有效分析。通过分析得到多个气室声波传播的规律,相较于单一气室,声波经过气室间的法兰时衰减幅度较大,且有一部分被反弹叠加等。因此选用的超声波传感器必须具备高灵敏度、宽频带等特点。同时由于气室外部声压较小,为避免信号失真需对采集信号进行放大处理。该仿真为超声波传感器检测GIS局放提供了理论指导基础。

To minimize the inconvenience of physical analysis of complex sound field effect caused by partial discharge of gas-insulated metal-enclosed switchgear, a fluid-solid coupling analysis model is established for the sound field. The coupling effect between the internal sound source and the central conducting rod and the external chamber of GIS is calculated and analyzed by finite element analysis method. Then the sound pressure distribution and propagation characteristics of the metal cylinder wall of GIS equipment are effectively analyzed. Through the analysis, the propagation law of sound wave in multiple chambers is obtained. Compared with the single chamber sound wave passing through the flange between the chambers, the attenuation range of sound wave is larger, and some of it is superimposed by rebound. Therefore, the selected ultrasonic sensor must have the characteristics of high sensitivity and wide frequency bandwidth. At the same time, because the sound pressure outside the chamber is small, in order to avoid signal distortion, the acquisition signal needs to be amplified and processed. The simulation provides a theoretical basis for the detection of GIS partial discharge by ultrasonic sensors.