基于振荡波局部放电检测的电力电缆绝缘老化状态评价与故障定位

Evaluation and fault location of power cable insulation aging based on oscillation-wave partial discharge detection

随着我国社会发展进步,电缆线路的铺设速度愈发加快。交联聚乙烯电缆凭借其优良的运行性能,在国内广泛铺设,但囿于复杂的运行环境,电缆常因此受到不同程度的绝缘老化。目前,在高压交联电缆线路现场试验和状态检测中,阻尼振荡波电压下的局部放电实验还未有重大突破,缺乏相关的实验数据。文中介绍了振荡波局部放电实验的原理及其实验装置,并对通过对比分析三条绝缘老化程度差异明显、在电缆接头与终端分别出现绝缘缺陷的电力电缆,得到了绝缘老化程度与电缆局部放电参数(放电起始电压、放电电量等)之间的相对关系。凭借局部放电定位的手段,进行了电缆绝缘老化故障的位置分析,并证明了阻尼振荡波电压下的局部放电实验的优良性与适用性。

With the progress of the social development of our country,the laying speed of the cable line is increasing.The cross-linked polyethylene cable is widely laid in the country by virtue of its excellent operating performance,but in a complex operating environment,the cable is often subjected to different degree of insulation aging.At present,in the field test and state detection of the high-voltage cross-link cable,there is no significant breakthrough in the partial discharge experiment under the voltage of the ringing wave,and the relevant experimental data is not available.In this paper,the principle of partial discharge experiment of oscillation wave and its experimental device are introduced.The relative relationship between the insulation aging degree and the partial discharge parameters(discharge initial voltage,discharge electricity,etc.)of the cable is obtained by comparing and analyzing three power cables withobvious difference ininsulation aging degree and insulation defects in the cable joint and terminal.By means of partial discharge location,the location analysis of cable insulation aging fault is carried out,and the advantages and applicability of partial discharge experiment under damping oscillatory wave voltage are proved.