摘要
10 k V XLPE电缆中间接头作为电缆绝缘的薄弱环节,任何绝缘缺陷都会产生局部放电,导致绝缘劣化甚至击穿。为研究不同缺陷下的放电特性,以一段150 m长的XLPE电缆作为试验对象,在75 m处设置可拔插式中间接头,试验设计和模拟压接管尖角未打磨、主绝缘环形划痕、压接处错用绝缘胶带3种典型缺陷模型,采用脉冲电流法对其放电信号进行检测。结果表明:压接管尖角未打磨时放电呈单极性,主绝缘存在纵向划痕时放电呈"馒头状"的双极性,压接处错用绝缘胶带时放电呈"平台状"的双极性;压接管尖角未打磨时放电频率较低,随电压升高线性增加;主绝缘存在纵向划痕时,随电压升高放电频率呈线性增加,压接处错用绝缘胶带时与主绝缘存在纵向划痕时的放电频率相差不大,随着电压升高放电频率会呈现先慢后快的增长趋势。
The middle joint of 10 kV XLPE cable is a weak link for cable insulation, any insulationdefects in the middle joint would produce partial discharge, and the partial discharge would lead to insulationdeterioration or even breakdown. In order to study the characteristics of different defects, we took a150 m long cable as a test object, which had a joint at 75 m. Three typical defects models, which werethe sharp angle of tube without sanding, the main insulation existing scratch, and the joint being misusedinsulating tape, were designed and simulated, and their PD signals were detected by pulse currentmethod. The results show that when the sharp angle of tube is without sanding, the partial dischargespectra show unipolarity, and the discharge frequency is low and increases linearly with the increase ofvoltage. When the main insulation exist scratch, the partial discharge spectra show bipolarity, and the dischargefrequency increases linearly with the increase of voltage. When the joints is misused insulatingtape, the partial discharge spectra shows bipolarity, and the discharge frequency, which is close to the dischargefrequency when the main insulation exist scratch, increases slow first and then fast.
出处
《绝缘材料》
CAS
北大核心
2014年第6期61-64,共4页
Insulating Materials
基金
广东电网公司职工技术创新项目(FSZC-2013-001)
关键词
XLPE
冷缩中间头
典型缺陷
局部放电
XLPE
shrinking middle joint
typical defects
partial discharge
