Eddy current loss modelling for torque‐motors

In this study, we propose a non-contact 80 kW, 60,000 rpm coaxial magnetic gear (CMG) model for high speed and high power applications. Two models with the same power but different radial and axial sizes were optimized using response surface methodology. Both models employed a Halbach array to increase torque. Also, an edge fillet was applied to the radial magnetized permanent magnet to reduce torque ripple, and an axial gap was applied to the permanent magnet with a radial gap to reduce eddy current loss. The models were analyzed using 2-D and 3-D finite element analysis. The torque, torque ripple and eddy current loss were compared in both models according to the materials used, including Sm2Co17, NdFeBs (N42SH, N48SH). Also, the structural stability of the pole piece structure was investigated by forced vibration analysis. Critical speed results from rotordynamics analysis are also presented.

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Development of Interior Permanent Magnet Motors with Concentrated Windings for Reducing Magnet Eddy Current Loss

IEEJ Transactions on Industry Applications ◽

10.1541/ieejias.129.1022 ◽

2009 ◽

Vol 129 (11) ◽

pp. 1022-1029 ◽

Cited By ~ 3

Author(s):

Katsumi Yamazaki ◽

Yuji Kanou ◽

Yu Fukushima ◽

Shunji Ohki ◽

Akira Nezu ◽

...

Keyword(s):

Permanent Magnet ◽

Eddy Current ◽

Eddy Current Loss ◽

Permanent Magnet Motors ◽

Current Loss ◽

Interior Permanent Magnet

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Helical retaining sleeve for eddy current loss reduction in high-speed SPM machine

Electrical Engineering ◽

10.1007/s00202-021-01218-4 ◽

2021 ◽

Author(s):

Mahir Al-ani ◽

Simon Barrans

Keyword(s):

Eddy Current ◽

High Speed ◽

Eddy Current Loss ◽

Loss Reduction ◽

Current Loss

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Eddy Current Loss in Grain-Oriented Steel Laminations due to Normal Leakage Flux

IEEE Transactions on Magnetics ◽

10.1109/tmag.2021.3069727 ◽

2021 ◽

pp. 1-1

Author(s):

Wei Wang ◽

Arne Nysveen ◽

Niklas Magnusson

Keyword(s):

Eddy Current ◽

Eddy Current Loss ◽

Current Loss ◽

Leakage Flux

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An Alternative Method for Calculating the Eddy Current Loss in the Sleeve of a Sealless Pump

Actuators ◽

10.3390/act10040078 ◽

2021 ◽

Vol 10 (4) ◽

pp. 78

Author(s):

Tomislav Strinić ◽

Bianca Wex ◽

Gerald Jungmayr ◽

Thomas Stallinger ◽

Jörg Frevert ◽

...

Keyword(s):

Eddy Current ◽

Three Dimensional ◽

Eddy Current Loss ◽

Theoretical Background ◽

Air Gap ◽

Magnetic Flux Density ◽

Pump Impeller ◽

Current Loss ◽

Faraday’S Law ◽

Transient Simulations

A sealless pump, also known as a wet rotor pump or a canned pump, requires a stationary sleeve in the air gap to protect the stator from a medium that flows around the rotor and the pump impeller. Since the sleeve is typically made from a non-magnetic electrically conductive material, the time-varying magnetic flux density in the air gap creates an eddy current loss in the sleeve. Precise assessment of this loss is crucial for the design of the pump. This paper presents a method for calculating the eddy current loss in such sleeves by using only a two-dimensional (2D) finite element method (FEM) solver. The basic idea is to use the similar structure of Ampère’s circuital law and Faraday’s law of induction to solve eddy current problems with a magnetostatic solver. The theoretical background behind the proposed method is explained and applied to the sleeve of a sealless pump. Finally, the results obtained by a 2D FEM approach are verified by three-dimensional FEM transient simulations.

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