摘要
通过研究电缆的热老化和辐照老化机理及其对绝缘材料介电性能的影响,探讨了基于电气性能对电缆进行无损检测的可行性。以两种交联聚烯烃材料的核级低压电缆为对象,通过加速老化试验模拟其全服役寿期,测试老化试样的断裂伸长率、红外光谱、氧化诱导温度以及介电损耗频谱,以研究电缆绝缘随热老化和辐照老化的性能下降规律。结果表明:热老化机理和辐照老化基本一致,都是基材的高分子链断裂氧化和添加剂(如抗氧化剂)含量减少共同作用的结果,其中添加剂的挥发对绝缘介电频谱的影响可能起主导作用。通过单个频率或某特定频率范围下的介质损耗大小来评价电缆绝缘热老化和辐照老化可能不具备普适性,而应在更宽的测试频段中获取信息。
The thermal and irradiation ageing mechanisms of cables and their effect on the dielectric properties of cable insulation were stdudied to discuss the feasibility of nondestructive testing of cables based on electrical properties. Two kinds of crosslinked polyolefin （XLPO） nuclear low voltage cables were accelerated aged to simulate their lifetime, and their elongation at break, FTIR, oxidation induction temperature, and dielectric loss frequency spectra were measured to research the property decline rule of cable insulation. The results show that the mechanism of thermal ageing is similar to that of irradiation ageing, both are the results of polymer chains break and oxidation and additives （such as antioxidant） content decrease, and the additives content decrease might be the main effect on the dielectric loss frequency spectra. It is not universal to evaluate the thermal and irradiation ageing condition of cable insulation according to the dielectric loss at certain frequency or in specific frequency range, and the spectra should be obtained in wider frequency range.
作者
张益舟
龚智明
王雷
汪亮
云浩
郑峥
Zhang Yizhou Gong Zhiming Wang Lei Wang Liang Yun Hao Zheng Zheng(Research Institute of Nuclear Power Operation, Wuhan 430223, China Fujian Fuqing Nuclear Power Co., Ltd., Fuqing 350318, China)
出处
《绝缘材料》
CAS
北大核心
2017年第9期62-67,共6页
Insulating Materials
关键词
核级电缆
热老化
辐照老化
状态监测
介损频谱
nuclear cable
thermal ageing
irradiation ageing
condition monitoring
dielectric loss frequen- cy spectra
