Study on ultra-low frequency dielectric loss test and evaluation regulation of cross-linked polyethylene cable insulation aging
ZHAO Lihui1, JIANG Xing1, QIAN Wei1, ZHANG Yong1, WANG Fenghua2
1. Qujing Qilin Power Supply Bureau, Yunnan Power Grid Co., Ltd, Qujing, Yunnan 655000; 2. State Grid Electric Power Research Institute Wuhan Nanrui Co., Ltd, Wuhan 430070
Abstract：In this paper, based on the basic principle of determining the aging degree of the cable by detecting the ultra-low frequency dielectric loss value of the cable, combined with the multiple sets of data measured in a certain area, this paper makes a preliminary judgment through the international regulation IEEE 400.2—2013, analyzes the variation law of the cable dielectric loss value under different conditions and its causes, and concludes that the regulation is only applicable to cables without local deterioration. In addition, due to the differences between China's cable manufacturing materials, structures and production processes and foreign products, it sometimes becomes inaccurate to judge the degree of cable aging by international regulations. In order to solve such problems, this paper establishes a more comprehensive criterion system and the establishment method of the optimal judgment threshold, and fits the measured data in the region as an example to obtain a more accurate grading judgment threshold. This method has certain reference significance for the establishment of evaluation rules in line with China's cable reality.
2021, Vol. 22 
