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Effect of Cooling Medium on LDPE Dielectric Properties
Polyethylene, with its excellent mechanical and dielectric properties is used as an insulator for high-voltage direct current (HVDC) transmission. In ultra-high-voltage direct current (UHVDC) transmission, the ageing of insulation materials caused by space charge under high DC voltage becomes seriou...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2022
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8838216/ https://www.ncbi.nlm.nih.gov/pubmed/35160415 http://dx.doi.org/10.3390/polym14030425 |
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author | Cheng, Yujia Yu, Guang Duan, Zhuohua |
author_facet | Cheng, Yujia Yu, Guang Duan, Zhuohua |
author_sort | Cheng, Yujia |
collection | PubMed |
description | Polyethylene, with its excellent mechanical and dielectric properties is used as an insulator for high-voltage direct current (HVDC) transmission. In ultra-high-voltage direct current (UHVDC) transmission, the ageing of insulation materials caused by space charge under high DC voltage becomes serious. Therefore, restraining the space charge and improving the dielectric properties of HVDC cables is important. In this study, low-density polyethylene (LDPE) was used as the raw material and combined with cooling media in a vulcanizing press. A polarizing microscope was used to observe the samples’ crystal morphologies. The space charge accumulation and dispersion were detected using pulsed electro-acoustic. Additionally, dielectric properties such as electrical conductivity and dielectric frequency spectrum were tested. The grain size in the air-cooled LDPE samples was found to be large and unevenly dispersed. However, the grain sizes in the water and oil cooling LDPE samples were small. The mean charge density of the oil cooling samples was the lowest. Under a short circuit measurement, more space charges were found in the natural and rapid air cooling samples. The mean charge densities of these two samples were high, with a fast decay rate. With an 8 and 50 kV/mm electric field strength, the oil cooling samples’ conductivity was the highest and lowest, respectively. |
format | Online Article Text |
id | pubmed-8838216 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-88382162022-02-13 Effect of Cooling Medium on LDPE Dielectric Properties Cheng, Yujia Yu, Guang Duan, Zhuohua Polymers (Basel) Article Polyethylene, with its excellent mechanical and dielectric properties is used as an insulator for high-voltage direct current (HVDC) transmission. In ultra-high-voltage direct current (UHVDC) transmission, the ageing of insulation materials caused by space charge under high DC voltage becomes serious. Therefore, restraining the space charge and improving the dielectric properties of HVDC cables is important. In this study, low-density polyethylene (LDPE) was used as the raw material and combined with cooling media in a vulcanizing press. A polarizing microscope was used to observe the samples’ crystal morphologies. The space charge accumulation and dispersion were detected using pulsed electro-acoustic. Additionally, dielectric properties such as electrical conductivity and dielectric frequency spectrum were tested. The grain size in the air-cooled LDPE samples was found to be large and unevenly dispersed. However, the grain sizes in the water and oil cooling LDPE samples were small. The mean charge density of the oil cooling samples was the lowest. Under a short circuit measurement, more space charges were found in the natural and rapid air cooling samples. The mean charge densities of these two samples were high, with a fast decay rate. With an 8 and 50 kV/mm electric field strength, the oil cooling samples’ conductivity was the highest and lowest, respectively. MDPI 2022-01-21 /pmc/articles/PMC8838216/ /pubmed/35160415 http://dx.doi.org/10.3390/polym14030425 Text en © 2022 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Cheng, Yujia Yu, Guang Duan, Zhuohua Effect of Cooling Medium on LDPE Dielectric Properties |
title | Effect of Cooling Medium on LDPE Dielectric Properties |
title_full | Effect of Cooling Medium on LDPE Dielectric Properties |
title_fullStr | Effect of Cooling Medium on LDPE Dielectric Properties |
title_full_unstemmed | Effect of Cooling Medium on LDPE Dielectric Properties |
title_short | Effect of Cooling Medium on LDPE Dielectric Properties |
title_sort | effect of cooling medium on ldpe dielectric properties |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8838216/ https://www.ncbi.nlm.nih.gov/pubmed/35160415 http://dx.doi.org/10.3390/polym14030425 |
work_keys_str_mv | AT chengyujia effectofcoolingmediumonldpedielectricproperties AT yuguang effectofcoolingmediumonldpedielectricproperties AT duanzhuohua effectofcoolingmediumonldpedielectricproperties |