NDLI: Microscopic study of a solid insulating material after breakdown under DC and AC voltages

Content Provider	IEEE Xplore Digital Library
Author	Mohanty, S. Ghosh, S. Panda, P.C.
Copyright Year	2012
Description	Author affiliation: Department of Electrical Engineering, National Institute Of Technology, Durgapur 751302 (INDIA) (Ghosh, S.) \|\| Department of Electrical Engineering, National Institute Of Technology, Rourkela 769008 (INDIA) (Mohanty, S.; Panda, P.C.)
Abstract	The monitoring of the state of the insulation and it's interpretation is an important and challenging task. In order to monitor the state of the insulation after application of various voltages under DC and AC conditions, the samples of the paper insulating material Leatherite paper was observed under Scanning Electron Microscope (SEM). The SEM (JEOL JSM-6480LV) was operated in low vacuum mode in order to observe the samples, which are difficult to view due to excessive surface charging. The experimental data were obtained by using a cylinder-plane electrode system with artificially created cavities punched at the centre of the sample. The SEM observations for the virgin samples of Leatherite paper (thickness of 0.13 mm) and the samples stressed with a voltage of 50%, 75% of breakdown voltage and on breakdown were taken under application of DC voltage. On comparison with a virgin sample, no indication of insulation deterioration was observed for the sample with the application of 50% of the breakdown voltage. However, at 75% of the breakdown voltage the center of the sample appears to be more whitish, indicating excessive charging of the sample. It indicates that the deterioration of sample has started. On breakdown, the sample clearly showed a puncture taking place right at the center as expected along with the whitish colour. The puncture was having an area of approximately 50 µm by 35 µm (1750 $µm^{2}).$ The puncture also implies that the center of the sample was highly stressed and the breakdown is mainly due to PD in cavities of the sample. Similar procedure was also adopted for the insulating samples of Leatherite paper under power frequency AC conditions and it is observed that the PD activity is more prominent under AC rather than DC and the puncture area of 180 µm by 100 µm (18000 $µm^{2})$ was found.
Starting Page	1
Ending Page	4
File Size	1313259
Page Count	4
File Format	PDF
ISBN	9781467328524
ISSN	21609241
e-ISBN	9781467328517
DOI	10.1109/ICPADM.2012.6318974
Language	English
Publisher	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Publisher Date	2012-07-24
Publisher Place	India
Access Restriction	Subscribed
Rights Holder	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Subject Keyword	Partial discharges Cable insulation Microscopy Breakdown voltage Electrodes Electron Microscopy Insulation breakdown Partial Discharge
Content Type	Text
Resource Type	Article

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in