TY - GEN
T1 - Role of degassing process on dielectric performance of XLPE cable insulation
AU - Li, Huan
AU - Li, Jianying
AU - Jia, Ran
AU - Zhang, Xu
N1 - Publisher Copyright:
© 2015 IEEE.
PY - 2015/10/8
Y1 - 2015/10/8
N2 - In this paper, the role of degassing process on dielectric performance of 110 kV XLPE cable insulation is investigated. The undegassed XLPE cable insulation is degassed at 70°C in laboratory for different duration in terms of heating time, to prepare XLPE samples with different weight loss ratio. Fourier Transform Infrared Spectroscopy (FTIR) test, electric breakdown test at 50 Hz, and Pulsed Electro-acoustic (PEA) measurement are carried out for XLPE samples. In FTIR spectrogram, the characteristic absorption peaks locate at 1680cm-1 and 1600cm-1, which can be relate to two kinds of crosslinking byproducts including α-methylstyrene and acetophenone, decrease with the increase of weight loss ratio. It can be proposed that weight loss of XLPE samples in the process of degassing treatment is caused by volatiliztion of α-methylstyrene and acetophenone. Therefore, the change of weight loss ratio can reflect the change of content of α-methylstyrene and acetophenone in XLPE. The results of electric breakdown test show that the reduction of α-methylstyrene and acetophenone leads to the enhancement of electric breakdown strength at 50 Hz. PEA measurement results show that heterocharge is produced and accumulated when cross-linking byproducts are present, whereas no heterocharge is found when a-methylstyrene and acetophenone are absent. The formation of heterocharge is attributed to ionization of cross-linking byproducts under electric stress. Based on these results above, it can be suggested that when ac electric field is applied on XLPE samples, the occurrence of ionization of cross-linking byproducts results in increase of free carriers in XLPE insulation, leading to a lower electric breakdown strength.
AB - In this paper, the role of degassing process on dielectric performance of 110 kV XLPE cable insulation is investigated. The undegassed XLPE cable insulation is degassed at 70°C in laboratory for different duration in terms of heating time, to prepare XLPE samples with different weight loss ratio. Fourier Transform Infrared Spectroscopy (FTIR) test, electric breakdown test at 50 Hz, and Pulsed Electro-acoustic (PEA) measurement are carried out for XLPE samples. In FTIR spectrogram, the characteristic absorption peaks locate at 1680cm-1 and 1600cm-1, which can be relate to two kinds of crosslinking byproducts including α-methylstyrene and acetophenone, decrease with the increase of weight loss ratio. It can be proposed that weight loss of XLPE samples in the process of degassing treatment is caused by volatiliztion of α-methylstyrene and acetophenone. Therefore, the change of weight loss ratio can reflect the change of content of α-methylstyrene and acetophenone in XLPE. The results of electric breakdown test show that the reduction of α-methylstyrene and acetophenone leads to the enhancement of electric breakdown strength at 50 Hz. PEA measurement results show that heterocharge is produced and accumulated when cross-linking byproducts are present, whereas no heterocharge is found when a-methylstyrene and acetophenone are absent. The formation of heterocharge is attributed to ionization of cross-linking byproducts under electric stress. Based on these results above, it can be suggested that when ac electric field is applied on XLPE samples, the occurrence of ionization of cross-linking byproducts results in increase of free carriers in XLPE insulation, leading to a lower electric breakdown strength.
KW - cross-linking byproducts
KW - degassing
KW - dielectric performance
KW - XLPE
UR - https://www.scopus.com/pages/publications/84962563924
U2 - 10.1109/ICPADM.2015.7295235
DO - 10.1109/ICPADM.2015.7295235
M3 - 会议稿件
AN - SCOPUS:84962563924
T3 - Proceedings of the IEEE International Conference on Properties and Applications of Dielectric Materials
SP - 168
EP - 171
BT - ICPADM 2015 - 2015 IEEE 11th International Conference on the Properties and Applications of Dielectric Materials
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 11th IEEE International Conference on the Properties and Applications of Dielectric Materials, ICPADM 2015
Y2 - 19 July 2015 through 22 July 2015
ER -