抑制局部放电老化影响的XLPE电缆绝缘缺陷识别
符方达1，杨旭2，潘成3，姚雨杭3，江翼2，张静2，王录亮1
（1 海南电网有限责任公司电力科学研究院，海南 海口 570000；2 国网电力科学研究院武汉南瑞有限责任公司，湖北 武汉 430074；
3 武汉大学 电气与自动化学院，湖北 武汉 430072）
摘 要：局部放电（PD）测量是检测甚至识别交联聚乙烯（XLPE）电缆绝缘缺陷的有效工具，设置了内半导电层破损、绝缘内部气隙缺陷、绝缘表面划痕缺陷和外半导电层爬电缺陷等四种绝缘缺陷，在直流条件下进行了各种缺陷的PD老化实验，发现PD在不同老化阶段表现出不同的特性，导致PD指纹参数随着老化时间产生波动。为了提高识别效果，提出了基于BRNN 算法的缺陷识别模型，由局部放电特征将局放序列划分为五个阶段，分别提取每个阶段下的指纹参数后再结合局部放电阶段信息作为BRNN算法输入。该方法将绝缘老化下局部放电的时序特性纳入考虑，将缺陷识别效率由72.93%提升至93.71%。
关键词：交联聚乙烯（XLPE）电缆；绝缘缺陷；局部放电（PD）老化；指纹参数；BRNN模型
中图分类号：TM726.4；TM855 文献标识码：A 文章编号：1007-3175(2020)04-0016-09
Identifying Insulation Defects of XLPE Cable with Suppressing the Influence of PD Aging
FU Fang-da1, YANG Xu2, PAN Cheng3, YAO Yu-hang3, JIANG Yi2, ZHANG Jing2, WANG Lu-liang1
（1 Hainan Electric Power Research Institute, Haikou 570000, China; 2 Wuhan Nari Electric Co., Ltd, Wuhan 430074, China;
3 School of Electrical Engineering and Automation, Wuhan University, Wuhan 430072, China）
Abstract: Partial discharge (PD) measurement is an effective tool for testing and even identifying the insulation defects of cross-linked polyethylene (XLPE) cables. Four kinds of defects were set, including internal semi-conductive layer damage, internal air gap of the insulation flaw, insulation surface scratch, and the outer semi-conductive layer creep.PD aging test with various defects were performed under DC conditions, and then found that PD showed different characteristics at different aging stages, which caused PD fingerprint parameters to fluctuate with aging time. In order to improve the recognition effect, a defect recognition model based on the BRNN algorithm is proposed. The partial discharge sequence is divided into five stages based on the partial discharge characteristics. The fingerprint parameters at each stage are extracted and combined with the partial discharge stage information as the BRNN algorithm input. This method takes into account the timing characteristics of partial discharge under insulation aging, and improves defect recognition efficiency from 72.93% to 93.71 %.
Key words: XLPE cable; insulation defects; PD aging; fingerprint parameters; BRNN model
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