基于阻尼振荡电压的电缆水树局部放电检测方法  

Partial discharge detection for water tree of power cable under oscillating wave

作　　者：李国城 李光茂 周鸿铃 陈璐 杜钢 郑服利 乔胜亚 LI Guocheng;LI Guangmao;ZHOU Honhling;CHEN Lu;DU Gang;ZHENG Fuli;QIAO Shengya(Electric Power Research Institute,Guangzhou Power Supply Bureau,Guangdong Power Grid Co.,Ltd.,Guangzhou 510030,China)

机构地区：[1]广东电网有限公司广州供电局电力科学研究院,广东广州510030

出　　处：《中国测试》2024年第S2期57-64,共8页China Measurement & Test

基　　金：中国南方电网有限责任公司科技项目(030111KK52222001,GDKJXM20222020)

摘　　要：随着社会的发展,电缆的应用越来越广泛。实际使用中,在多种因素的共同作用下,会导致绝缘老化失效而引发故障,最主要的方式之一是水树老化。国内外对于阻尼振荡电压对水树的检测是否有效仍处于一个争论的阶段,为此该文探讨了振荡波对水树局部放电的检测是否敏感进行研究。首先,使用水树培养模型对XLPE切片进行水树老化的培养,获得70%~95%老化程度的切片,通过与空白对照组无缺陷以及仅有0.5mm刀口缺陷的对比,验证阻尼振荡电压水树老化检测的有效性,再通过改变振荡波对电容充电保持的预加压时间,获得不同的水树局部放电特征,最后仿真分析水树培养模型在实验中的电场分布及场强分析,研究不同预加压时间对水树局部放电激励的特点。通过实验结果和分析,验证了阻尼振荡电压较工频电压对水树老化检测更具有效性,且由于存在直流加压时间,提高了水树的检出率。通过改变预加压时间,不同程度的水树老化缺陷的PDIV均存在饱和效应,当老化程度越明显时,PDIV越低,以及饱和曲线斜率越低,越早达到饱和,且最大局部放电量有明显的增加。With the development of society,the application of cable is more and more extensive.In actual use,under the joint action of various factors,insulation aging failure will be caused,and one of the most important ways is water tree aging.At home and abroad,there is still a debate on whether the damped oscillation voltage i s effective in detecting water tree.For this,we will discuss whether the oscillation wave is sensitive to the detection of partial discharge in water tree.First,use the water tree culture model to culture XLPE slices for water tree aging,and obtain 70%-95%of the slices with aging degree.By comparing with the blank control group,which has no defects and only 0.5mm knife edge defects,verify the effectiveness of water tree aging detection with damping oscillation voltage.Then,by changing the pre pressurization time of oscillation wave for capacitor charging,obtain different partial discharge characteristics of water tree,Finally,the electric field distribution and field strength analysis of the water tree culture model in the experiment are simulated and analyzed,and the characteristics of partial discharge excitation of water tree under different pre pressurization time are studied.Through the experimental results and analysis,it is verified that the damping oscillation voltage is more effective than the power frequency voltage for water tree aging detection,and the detection rate of water tree is improved due to the existence of DC pressurization time.By changing the pre pressurization time,the PDIV with water tree aging defects at different levels has saturation effect.When the aging degree is more obvious,the lower the PDIV and the lower the slope of the saturation curve,the earlier it reaches saturation,and the maximum local discharge has a significant increase.

关 键 词：阻尼振荡电压 水树 局部放电 XLPE 

分 类 号：TM855[电气工程—高电压与绝缘技术]