mdh.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Evaluation of magnetic aging in transformers and electrical machines cores during operation: Modelling
Mälardalen University, Department of Public Technology. (Process control and simulation)
Mälardalen University, Department of Public Technology.
Mälardalen University, Department of Public Technology.ORCID iD: 0000-0002-7233-6916
Surahammars Bruks AB, R&D.
2009 (English)In: Proceedings of the Scientific Conference on Energy and IT at Älvsjö fair, Stockholm March 11-12, 2009 in connection with the “Energitinget 2009, 2009, p. 218-232Conference paper, Published paper (Refereed)
Abstract [en]

Electric steels are processed to avoid the phenomenon known as magnetic aging. Non-oriented electrical steels are mostly used in rotating electrical machines and oriented steels used in transformers, which during operation generates heat. This could cause carbide precipitation/coalescence in the metallic matrix, impairing the magnetic properties of the steel, called magnetic aging. The steel has to contain very little carbon to avoid aging. This is achieved during the making of the steel or by a decarburising annealing of the final thickness strip or of the stamped laminations.

The magnetic material for cores of a transformer and electrical machines should be characterised by high permeability and low energy losses in changing magnetic flux.

In order to test that the magnetic properties do not become worse during these working conditions, the steel can be tested for magnetic ageing. The European standard defines the test cycle as 225°C for 24 hours. The American ASTM standard suggests two different cycles: 100 hours at 150°C or 600 hours at 100 °C.

 

A test the losses after a heat treatment of 150°C f or 10 days for coils with higher carbon content than 26 ppm of the final product has performed here. This longer cycle has proved to give larger increases in the loss than the shorter one according to the European standard.

The ageing process was much faster for a higher carbon content slab with 90 ppm C than for a lower one with 30 ppm C.

ANN method using LMS has performed to aging real time identification. Results showed a 97% best fit. It showed that using ANN can predict the aging and a modern advanced relay can control the loading and temperature of electrical equipments to prevent of harmful damages.

Place, publisher, year, edition, pages
2009. p. 218-232
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Energy- and Environmental Engineering
Identifiers
URN: urn:nbn:se:mdh:diva-6839ISBN: 978-91-977493-4-3 (print)OAI: oai:DiVA.org:mdh-6839DiVA, id: diva2:236010
Conference
International Scientific Conference on “Energy systems with IT” in connection with the Energiting 2009, March 11-12 at Älvsjö fair, Stockholm.
Projects
KKS projectAvailable from: 2009-09-19 Created: 2009-09-19 Last updated: 2016-01-08Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

http://mdh.diva-portal.org/smash/get/diva2:293132/FULLTEXT01.pdf

Authority records BETA

Dahlquist, Erik

Search in DiVA

By author/editor
Mousavi Takami, KouroshMahmoudi, JafarDahlquist, Erik
By organisation
Department of Public Technology
Other Electrical Engineering, Electronic Engineering, Information Engineering

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 963 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf