Affiliation:
1. State Grid Hebei Electric Power Research Institute, Shijiazhuang 050021, China
2. Institute of Advanced Electrical Materials, Qingdao University of Science and Technology, Qingdao 266042, China
Abstract
Thermal aging is one of the main reasons for the degradation of insulation properties of high voltage cable. Dielectric properties and breakdown strength are important parameters to reflect the insulation performance of the cable insulation materials. In the work, the influence of thermal aging on dielectric and breakdown performance of the cable insulation layer was studied. Firstly, XLPE cable insulation samples were prepared and the thermal aging treatment was carried out. Secondly, the microstructure and molecular structure of XLPE samples under different thermal aging time were analyzed. The dielectric properties and breakdown characteristics of XLPE samples under different thermal aging times were characterized in macro aspect. Finally, the effects of different temperatures on the molecular microstructure of XLPE were studied. The results show that with the extension of thermal aging time, the microstructure of XLPE molecule is destroyed, the macromolecular chain is gradually cleaved, and the carbonyl absorption intensity increases. At power frequency, the breakdown strength decreases from 75.37 kV/mm to 62.18 kV/mm, the relative permittivity increases from 2.44 to 2.51, and the dielectric loss increases from 1.47 × 10−4 to 3.10 × 10−3. The free volume rate of XLPE molecules increases with the increasing temperature, and the mean square displacement gradually increases. The work has good guiding significance for the safe operation and condition assessment of high-voltage cables.
Funder
Shandong Province universities Youth Innovation Technology Support Plan
Subject
Materials Chemistry,Surfaces, Coatings and Films,Surfaces and Interfaces
Reference25 articles.
1. Crosslinking characteristic and mechanism of cross-linked polyethylene insu-lating materials used for high voltage direct current cables;Li;High Volt. Eng.,2017
2. Conductive properties of carbon black-polyethylene composites;Lei;HIET J.,1990
3. Terahertz-Based Insulation Delamination Defect Inspection of Vehicle Cable Terminals;Li;IEEE Trans. Transp. Electrif.,2023
4. Li, S., Cao, B., Kang, Y., Cui, Y., and Dong, H. (2021). Nonintrusive Inspection of Moisture Damp in Composited Insulation Structure Based on Terahertz Technology. IEEE Trans. Instrum. Meas., 70.
5. Accelerated thermal ageing characteristics of XLPE cable insulation;Hu;Insul. Mater.,2020
Cited by
2 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献