表面金属异物引起盆式绝缘子局部放电的研究

Study on the Surface Partial Discharge of Basin-type Insulator Initiated by Metal Objects

为探究盆式绝缘子表面积聚的金属异物对其绝缘性能的影响,在正常盆式绝缘子表面沿电场方向附上细长的金属丝模拟缺陷,通过改变金属丝的长度、半径和位置,模拟不同程度或不同位置的金属颗粒积聚现象,同时进行试验和电场仿真分析。研究结果表明:绝缘子表面金属颗粒会使局部电场发生严重畸变,显著降低绝缘子表面击穿电压,最终造成绝缘子沿面放电和绝缘破坏;仿真和试验得到的结果很接近,在试验条件不充分的情况下可以通过仿真计算预测盆式绝缘子的绝缘状态;金属异物积聚越多或位置越靠近高压端导体,对绝缘子的危害越大。

To explore the influence of basin-type insulator surface of the metal particles to its insulating properties, On normal basin insulator surface along the field direction, attach the elongated metal wire analog defect. By changing the length, radius and position of the wire, simulate the metal particles accumulate phenomenon at different degrees or different locations while conducting a test and electric field simulation. The results show that： the metal particles of the insulator surface causes severe distortion of the local electric field reduce the breakdown insulator flashover voltage significantly, and leading to the insulator surface discharge and insulation damage eventually. Simulation and experiment results are very close. Under the insufficient experimental conditions, basin insulator insulated state can be predicted by simulation calculation. The more metalobjects accumulated or positions closer to the high-pressure side conductor, there are the greater harm to the insulator.