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Publikācija: Dynamic Air Gap Change of Low-Speed Generator Considering Thermal Expansion

Publication Type Scientific article indexed in SCOPUS or WOS database
Funding for basic activity Unknown
Defending: ,
Publication language English (en)
Title in original language Dynamic Air Gap Change of Low-Speed Generator Considering Thermal Expansion, Centrifugal Force and Magnetic Force Effects
Field of research 2. Engineering and technology
Sub-field of research 2.3 Mechanical engineering
Authors Marina Čerpinska
Rihards Elmanis-Helmanis
Keywords air gap, hydropower unit, magnetic force, inertia force
Abstract The paper provides the data collected over a three-year period to illustrate the dynamic air gap change depending on generation modes of four hydropower generators with similar design. The tests were performed on hydropower units at the rated apparent power of 105 MVA and the air gap of 20 mm. The results obtained showed that the average air gap change in different modes could reach up to 2.1 mm. Around 90 % of air gap change results from thermal expansion and 10 % were determined by centrifugal and magnetic forces. In coasting mode when the power was switched off and the angular velocity of the generator decreased, the air gap increased up to 0.7 mm. Attraction forces resulting from magnetic phenomena accounted for 0.1–0.6 mm decrease in the air gap.
DOI: 10.1515/lpts-2017-0031
Hyperlink: https://www.degruyter.com/downloadpdf/j/lpts.2017.54.issue-5/lpts-2017-0031/lpts-2017-0031.pdf 
Reference Čerpinska, M., Elmanis-Helmanis, R. Dynamic Air Gap Change of Low-Speed Generator Considering Thermal Expansion, Centrifugal Force and Magnetic Force Effects. Latvian Journal of Physics and Technical Sciences, 2017, Vol.5, No.5, pp.26-37. ISSN 0868-8257. Available from: doi:10.1515/lpts-2017-0031
Additional information Citation count:
ID 26290