Correlation between Terahertz Dielectric Properties of XLPE and Its Composition Structure during Electrothermal Aging

• DOI: 10.1021/acs.macromol.2c01197
• Publication Date: 2022-09-09T20:50:00Z
• Authors: Nuo Xu; Lisheng Zhong; Rui Sui; Muneeb Ahmed; Fei Li; Yongbin Liu; Jinghui Gao
• Keywords: 0103 physical sciences; 01 natural sciences

The electrothermal aging process of cross-linked polyethylene (XLPE) insulation has been an essential factor for the reliability high-voltage (HV) cables, but underlying mechanism remains a puzzle. In this paper, dielectric properties in terahertz domain sliced XLPE samples from HVDC cable are investigated at duration up to 1500 h. It is found that with increase time, real part and imaginary complex permittivity decrease increase, respectively. To explain phenomenon, chemical changes crystallinity characterized by Fourier transform infrared spectrum (FTIR) differential scanning calorimetry (DSC), proven declined positively correlated using effective medium theory. Furthermore, comparing response unaged aged different temperatures, appearance small polar molecules be responsible rise permittivity.