Experimental Evaluation of a Rare Earth-Free Permanent Magnet Generator

Low speed, high torque machines are used in wind turbines where the turbine rotor is directly connected to the generator. A permanent magnet synchronous generator using high-energy rare-earth permanent magnets (PMs) is one common choice for this application, but rare-earth PMs have supply insecuriti...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:IEEE transactions on energy conversion Jg. 36; H. 1; S. 3 - 10
Hauptverfasser: Eklund, Petter, Sjolund, Jonathan, Berg, Marcus, Leijon, Mats, Eriksson, Sandra
Format: Journal Article
Sprache:Englisch
Veröffentlicht: New York IEEE 01.03.2021
The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Schlagworte:
Electrical machines
Electrical measurement
end effects
Engineering Science with specialization in Science of Electricity
experiment
experimental evaluation
Ferrite permanent magnets
Ferrites
finite element methods
Generators
Low speed
Magnetic fields
Magnetism
Mathematical analysis
performance evaluation
permanent magnet generator
Permanent magnet generators
permanent magnet machines
Permanent magnets
Rare earth elements
rare earth free permanent magnet
Rotors
Simulation
Soft magnetic materials
Solid modeling
spoke-type rotor
Stators
Teknisk fysik med inriktning mot elektricitetslära
Two dimensional displays
Wind turbines
ISSN:0885-8969, 1558-0059, 1558-0059
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Low speed, high torque machines are used in wind turbines where the turbine rotor is directly connected to the generator. A permanent magnet synchronous generator using high-energy rare-earth permanent magnets (PMs) is one common choice for this application, but rare-earth PMs have supply insecurities and cost risks. A rare-earth free 32-pole PM generator, using ferrite PMs in a spoke-type rotor, for use in a 12 kW experimental wind turbine is built and tested. Voltages and currents at load and no load are measured, as well as the magnetic field in the end regions of the machine. The generator can deliver the required power at nominal speed and has low harmonic content in the output. The electrical measurements are compared to two-dimensional finite element design calculations and the experimental results are lower than expected from simulations. The measured voltage is lower than expected, requiring a higher current than calculated for the rated power. Three-dimensional magnetic field simulations show that there are leakage flux paths in the end-regions that the two-dimensional design calculations overlook, explaining the discrepancy between simulations and measurements.
Bibliographie:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
ISSN:0885-8969
1558-0059
1558-0059
DOI:10.1109/TEC.2020.3000594