The University of Southampton
University of Southampton Institutional Repository

Space charge measurement and analysis in low density polyethylene films

Space charge measurement and analysis in low density polyethylene films
Space charge measurement and analysis in low density polyethylene films
The growing requirement of reliability for an insulation system gives researchers greater responsibility to investigate new techniques for monitoring and diagnosing dielectrics subjected to an electric field. It is well known that the presence of space charge is one of the important factors causing premature failure of polymeric high voltage cables. Space charge surveillance is becoming the most general applied skill to evaluate polymeric materials, particularly high voltage cables. The well-known pulsed electroacoustic method (PEA), a reliable non-destructive method, gives a reasonable resolution to the concentration of the space charge in the insulation material. My work contributes to the measuring of space charge in low density polyethylene using PEA.
From the experiments to study space charge formation and distribution at the interface on multi-layer sample under DC and AC applied voltage, electrode materials and frequency are determined as two important factors in measuring the charge injection and distribution; the interface between films acts as a trap for charge carriers, especially for electrons; and positive charge has a high mobility compared to negative charge.
Surface potential decay was studied to explain the crossover phenomenon and to find physical mechanism on charge decay of the corona charged film sample. Charge mapping technique (PEA) was successfully introduced to the potential study and it provides an alternative way to investigate charge decay process and allows monitoring charge migration through the bulk of corona charged film. One essential phenomenon, bipolar charge injection, has been first derived from the results of space charge distribution.
The advanced PEA measurement system with high rate test and excellent phase resolving capability was designed in the last part of the study. Compared with the old system the new system can provide the enhanced experiment result for fast change situation, which can achieve high-quality diagnosis for the virtual industry situation such as polarity reversal and transient voltage failure.
Xu, Zhiqiang
797f8b0e-a035-4cf9-ac3f-99098a3fdb50
Xu, Zhiqiang
797f8b0e-a035-4cf9-ac3f-99098a3fdb50
Chen, George
3de45a9c-6c9a-4bcb-90c3-d7e26be21819

Xu, Zhiqiang (2009) Space charge measurement and analysis in low density polyethylene films. University of Southampton, School of Electronics and Computer Science, Doctoral Thesis, 222pp.

Record type: Thesis (Doctoral)

Abstract

The growing requirement of reliability for an insulation system gives researchers greater responsibility to investigate new techniques for monitoring and diagnosing dielectrics subjected to an electric field. It is well known that the presence of space charge is one of the important factors causing premature failure of polymeric high voltage cables. Space charge surveillance is becoming the most general applied skill to evaluate polymeric materials, particularly high voltage cables. The well-known pulsed electroacoustic method (PEA), a reliable non-destructive method, gives a reasonable resolution to the concentration of the space charge in the insulation material. My work contributes to the measuring of space charge in low density polyethylene using PEA.
From the experiments to study space charge formation and distribution at the interface on multi-layer sample under DC and AC applied voltage, electrode materials and frequency are determined as two important factors in measuring the charge injection and distribution; the interface between films acts as a trap for charge carriers, especially for electrons; and positive charge has a high mobility compared to negative charge.
Surface potential decay was studied to explain the crossover phenomenon and to find physical mechanism on charge decay of the corona charged film sample. Charge mapping technique (PEA) was successfully introduced to the potential study and it provides an alternative way to investigate charge decay process and allows monitoring charge migration through the bulk of corona charged film. One essential phenomenon, bipolar charge injection, has been first derived from the results of space charge distribution.
The advanced PEA measurement system with high rate test and excellent phase resolving capability was designed in the last part of the study. Compared with the old system the new system can provide the enhanced experiment result for fast change situation, which can achieve high-quality diagnosis for the virtual industry situation such as polarity reversal and transient voltage failure.

Text
PhD_Thesis__Final_Version_Z.Xu.pdf - Other
Download (4MB)

More information

Published date: July 2009
Organisations: University of Southampton

Identifiers

Local EPrints ID: 69927
URI: http://eprints.soton.ac.uk/id/eprint/69927
PURE UUID: 27e15c61-d040-49d9-847c-704811991919
ORCID for Zhiqiang Xu: ORCID iD orcid.org/0000-0002-6640-7335

Catalogue record

Date deposited: 20 Jan 2010
Last modified: 14 Mar 2024 02:56

Export record

Contributors

Author: Zhiqiang Xu ORCID iD
Thesis advisor: George Chen

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×