电缆终端安装刀痕缺陷的局部放电特性分析

摘要

For detecting typical installation of cutting defects in cable terminations, two kinds of common installing cutting defects in cable terminations are previously designed and their PD (Partial Discharge) characteristics are also investigated. In order to expose PD characteristics in real operation conditions, an accelerating aging platform for cable terminations is set up. Moreover, by using a Rogowski coil PD sensor, defects’ PD characteristics including single discharge pulse, frequency spectrum and PRPD (Phase Resolved Partial Discharge) patterns are recorded and analyzed. In addition, PD characteristics of the two kinds of defects are compared. The experimental results show that the two kinds of defects are obviously different in time and frequency domain. Also, the significant differences in discharge strength are observed for the two kinds of defects after a short time (240 hours) aging. These characteristics can be used for recognizing defects and improving installation technique.%　　为了在电缆终端运行初期检测出其典型安装刀痕缺陷，设计了电缆终端的两种常见刀痕缺陷，并对缺陷的局部放电特征进行了分析。通过电缆附件老化平台模拟真实工况并加速老化，使电缆终端缺陷的局部放电(Partial Discharge，PD)特征更为明显，并使用罗氏线圈传感器获取了不同刀痕缺陷下的PD数据，分析了不同刀痕缺陷的单个放电脉冲波形、放电频谱以及放电相位分布等特征。此外，将这两种缺陷的放电特性进行了对比分析。实验结果表明，不同缺陷下PD的时频特性各有不同；而且在短时间(240 h)老化的情况下，不同刀痕缺陷的放电程度就已表现出明显差异，这些特征可为缺陷识别以及改进电缆终端安装工艺提供依据。