The University of Southampton
University of Southampton Institutional Repository

The feasibility of using UHF sensors to measure partial discharges in liquid nitrogen

The feasibility of using UHF sensors to measure partial discharges in liquid nitrogen
The feasibility of using UHF sensors to measure partial discharges in liquid nitrogen
Liquid nitrogen (LN2) has been proposed as a coolant for high temperature superconducting (HTS) applications also as electrical insulation. Partial discharge (PD) activity indicates overstressing of the liquid dielectric or contamination which may provide an indication of the health of the dielectric and provide a useful precursor to the electric failure of LN2. The conventional method for PD measurements is restricted to a narrow bandwidth (less than 600 kHz). It has been shown that streamer discharges in liquid dielectrics consist of many small pulses, which due to the limited bandwidth of the PD detector would be integrated overtime by conventional equipment and recorded as single pulse [1]. The application of ultra high frequency (UHF) sensors can provide greater precision in the measurement of the discharge pulses during the pre-breakdown streamer phenomena in LN2. In addition, the UHF technique can be installed as on-line monitoring system with the capability of locating the discharge sources using the time-of-flight method, as has been proposed for oil filled transformer designs [8]. This paper explores the use of UHF sensors to measure PD in LN2. The experiments utilise a point to plane electrode configuration located inside a cryostat with high voltage bushing rated to 50kV PD free [2]. The sensor is mounted on the outside wall of the cryostat with uses of dielectric windows and signals are captured by a digital oscilloscope with a bandwidth of 2.5GHz. The conventional PD technique (IEC 60270) is also applied simultaneously and the results are presented and compared.
978-82-594-3525-5
CD-ROM
Truong, L H
a52e7edc-a28b-4a9c-ac7b-9251d45bb769
Swaffield, D J
31f6f52e-fb48-44f9-99d3-3cbd2539f1b9
Lewin, P L
78b4fc49-1cb3-4db9-ba90-3ae70c0f639e
Judd, M D
87cb96de-3216-4824-9092-1465c90a5a13
Truong, L H
a52e7edc-a28b-4a9c-ac7b-9251d45bb769
Swaffield, D J
31f6f52e-fb48-44f9-99d3-3cbd2539f1b9
Lewin, P L
78b4fc49-1cb3-4db9-ba90-3ae70c0f639e
Judd, M D
87cb96de-3216-4824-9092-1465c90a5a13

Truong, L H, Swaffield, D J, Lewin, P L and Judd, M D (2011) The feasibility of using UHF sensors to measure partial discharges in liquid nitrogen. 17th IEEE International Conference on Dielectric Liquids, Trondheim, Norway. 26 - 30 Jun 2011. CD-ROM .

Record type: Conference or Workshop Item (Paper)

Abstract

Liquid nitrogen (LN2) has been proposed as a coolant for high temperature superconducting (HTS) applications also as electrical insulation. Partial discharge (PD) activity indicates overstressing of the liquid dielectric or contamination which may provide an indication of the health of the dielectric and provide a useful precursor to the electric failure of LN2. The conventional method for PD measurements is restricted to a narrow bandwidth (less than 600 kHz). It has been shown that streamer discharges in liquid dielectrics consist of many small pulses, which due to the limited bandwidth of the PD detector would be integrated overtime by conventional equipment and recorded as single pulse [1]. The application of ultra high frequency (UHF) sensors can provide greater precision in the measurement of the discharge pulses during the pre-breakdown streamer phenomena in LN2. In addition, the UHF technique can be installed as on-line monitoring system with the capability of locating the discharge sources using the time-of-flight method, as has been proposed for oil filled transformer designs [8]. This paper explores the use of UHF sensors to measure PD in LN2. The experiments utilise a point to plane electrode configuration located inside a cryostat with high voltage bushing rated to 50kV PD free [2]. The sensor is mounted on the outside wall of the cryostat with uses of dielectric windows and signals are captured by a digital oscilloscope with a bandwidth of 2.5GHz. The conventional PD technique (IEC 60270) is also applied simultaneously and the results are presented and compared.

Text
ICDL29.pdf - Version of Record
Restricted to Registered users only
Download (1MB)
Request a copy

More information

Published date: 26 June 2011
Additional Information: Event Dates: 26 -30 June 2011
Venue - Dates: 17th IEEE International Conference on Dielectric Liquids, Trondheim, Norway, 2011-06-26 - 2011-06-30
Organisations: Electronics & Computer Science, EEE

Identifiers

Local EPrints ID: 272564
URI: http://eprints.soton.ac.uk/id/eprint/272564
ISBN: 978-82-594-3525-5
PURE UUID: e4aa265f-57ec-4182-a817-c66660fb3c0d
ORCID for P L Lewin: ORCID iD orcid.org/0000-0002-3299-2556

Catalogue record

Date deposited: 12 Jul 2011 14:24
Last modified: 15 Mar 2024 02:43

Export record

Contributors

Author: L H Truong
Author: D J Swaffield
Author: P L Lewin ORCID iD
Author: M D Judd

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.

×