紫外成像法的GIS盆式绝缘子局部放电研究

Research on Partial Discharge Characteristics of GIS Insulating Spacers Based on UV Imaging Method

气体绝缘组合电器(gas insulated switchgear,GIS)在电力系统中占有重要地位,盆式绝缘子是GIS内部重要的部件,其表面放电是影响GIS安全运行的重要因素,文中在盆式绝缘子表面设置了典型的绝缘缺陷模型,利用紫外成像仪记录了其表面放电引起紫外光子发射的整个过程,分析了典型放电缺陷模型下的放电电压与光子数之间的关系,对绝缘子表面放电进行了探索,取得的结论:1表面放电紫外光子数随着缺陷尺寸的增大有增大趋势,但是多次重复性实验表明存在饱和特性;2当模拟的同一种绝缘缺陷位于盆式绝缘子不同位置的时候,放电初始电压不同,相同电压下的光子数目也存在较大差异;3当绝缘缺陷距离导杆距离大于6 cm时,在相同电压下的放电明显减弱,产生的紫外光子数也明显减少。这些结论有助于后续对盆式绝缘子表面电荷特性的深入研究,同时也为现场检测GIS局部放电提供了依据。

Gas insulated switchgears （GIS） occupy an important position in the power system. Discharge on insulating spacer surface is an important factor influencing the safe operation of GIS. The authors set up different insulation defect models on insulating spacer surface and use UV camera to observe the surface discharge phenomena. Conclusions are drawn that： （1）The ultraviolet photon number increases with the increasing length of the insulation defect models, however, saturation characteristic is observed in repetitive experiments; （2）The initial discharge voltage ant the photon number under certain voltage significantly depend on the position of an insulation defect; （3）When the distance between an insulation defect and the guide bar is more than 6 cm, the discharge weakens obviously under the same voltage, and the corresponding ultraviolet photon number reduces significantly. These conclusions are helpful to the further study on the characteristics of insulator surface charge, and to the on-site detection of GIS partial discharge.