<abstract xmlns="http://www.w3.org/1999/xhtml"><p> 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 speed 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.</p></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 speed 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.

Dynamic Air Gap Change of Low-Speed Generator Considering Thermal Expansion, Centrifugal Force and Magnetic Force Effects

Latvian Journal of Physics and Technical Sciences

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

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...

Dynamic Air Gap Change of Low-Speed Generator Considering Thermal Expansion, Centrifugal Force and Magnetic Force Effects

Published Online: Nov 22, 2017

Page range: 26 - 37

Received: Jul 04, 2017

DOI: https://doi.org/10.1515/lpts-2017-0031

Keywords
air gap, centrifugal force, hydropower unit, magnetic force

© by M. Cerpinska

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Dynamic Air Gap Change of Low-Speed Generator Considering Thermal Expansion, Centrifugal Force and Magnetic Force Effects

Published Online: Nov 22, 2017

Page range: 26 - 37

Received: Jul 04, 2017

DOI: https://doi.org/10.1515/lpts-2017-0031

Keywordsair gap, centrifugal force, hydropower unit, magnetic force

© by M. Cerpinska

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
air gap, centrifugal force, hydropower unit, magnetic force