An Analytical Method for Predicting 3-D Eddy Current Loss in Permanent Magnet Machines Based on Generalized Image Theory

Chen, Liang; Wang, Jiabin; Nair, Sreeju S.

doi:10.1109/tmag.2015.2500878

Cited by 31 publications

(28 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This ensures the eddy current sources [29] seen by the magnets are referred in the rotor coordinate system. Hence the flux density values at an angular position w.r.t the rotating co-ordinate system attached to the magnets at time can be calculated as, .…”

Section: Implementation Of 2d Fea Results In the Proposedmentioning

confidence: 99%

“…For the machine under consideration 32 divisions are considered for the unsegmented magnet length ( ) along the axial direction. 3D FFT is performed to evaluate the source coefficients and hence the eddy current density coefficients [29]. The eddy current loss in every magnet is calculated at each time step and the analysis are repeated for 1/6 th electrical cycle to predict the average loss.…”

Section: Implementation Of 2d Fea Results In the Proposedmentioning

confidence: 99%

“…Machine Topology and Design Parameters The analytical part of the imaging method for predicting resistance limited 3D eddy current distribution and the total eddy current loss has been presented in [29] .Without loss of generality, the imaging method is implemented on the 8-pole,18-slot IPM machine [30] employing V shaped NdFeB magnets with its cross section as shown in Fig.1. The machine topology benefits from low-space harmonics [31] and, hence, low eddy current loss, improved reluctance torque and less demagnetization risk.…”

Section: Implementation Of Proposed Methods For Ipm Machinesmentioning

confidence: 99%

“…The method of generalized imaging is proposed in [29] to evaluate the resistance limited eddy current distribution which satisfies its natural boundary condition for the magnets in a SPM machine neglecting any curvature effects. The method establishes the distribution of magnetic field variation with time as the sources of the eddy current fields in the form of 3D Fourier series in directions.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Computationally Efficient 3-D Eddy Current Loss Prediction in Magnets of Interior Permanent Magnet Machines

et al. 2016

Self Cite

View full text Add to dashboard Cite

--This paper proposes a computationally efficient method based on imaging technique, for accurate prediction of 3-dimensional (3D) eddy current loss in the rotor magnets of interior permanent magnet (IPM) machines. 2D time-stepped finite element analysis is employed to generate the radial and the tangential 2D magnetic field information within the magnet for application of the 3D imaging technique. The method is validated with 3D time-stepped finite element analysis (FEA) for an 8 pole-18 slot IPM machine evaluating its resistance limited magnet loss with increase in axial and tangential segmentation. Magnet loss considering eddy current reaction at high frequencies is evaluated from the proposed method by employing the diffusion of the 2D magnetic field variation along the axial plane. The loss associated with all the frequencies together in the armature currents is evaluated by considering each of the harmonics separately in the proposed method employing the frozen permeability to account for magnetic saturation. The results obtained are verified with 3D FEA evaluating the magnet loss at fundamental, 10 and 20 kHz time harmonics in armature currents.Index Terms-Eddy current loss, finite element, frozen permeability, imaging method, permanent magnets.

show abstract

Section: Implementation Of 2d Fea Results In the Proposedmentioning

confidence: 99%

Section: Implementation Of 2d Fea Results In the Proposedmentioning

confidence: 99%

Section: Implementation Of Proposed Methods For Ipm Machinesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Computationally Efficient 3-D Eddy Current Loss Prediction in Magnets of Interior Permanent Magnet Machines

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…Eddy current losses have been studied in electrical machines with two-dimensional as well as more accurate three-dimensional simulations [13][14][15]. For some applications, especially in high-speed machines, they could become a problem [16].…”

Section: Introductionmentioning

confidence: 99%

Investigation of Permanent Magnet Demagnetization in Synchronous Machines during Multiple Short-Circuit Fault Conditions

Sjökvist

Eriksson

2017

Energies

View full text Add to dashboard Cite

Faults in electrical machines can vary in severity and affect different parts of the machine. This study focuses on various kinds of short-circuits on the terminal side of a generic 20 kW surface mounted permanent magnet synchronous generator and how successive faults affect the performance of the machine. The study was conducted with the commercially available finite element method software COMSOL Multiphysics R , and two time-dependent models for demagnetization of permanent magnets were compared, one using only internal models and the other using a proprietary external function. The study is simulation based and the two models were compared to a previously experimentally verified stationary model. Results showed that the power output decreased by more than 30% after five successive faults. In addition, the no-load voltage had become unsymmetrical, which was explained by the uneven demagnetization of the permanent magnets. The permanent magnet with the lowest reduction in average remanence was decreased by 0.8%, while the highest average reduction was 23.8% in another permanent magnet. The internal simulation model was about four times faster than the external model, but slightly overestimated the demagnetization.

show abstract

Analytical modelling and analysis of magnet eddy current loss in magnet‐surrounded permanent magnet synchronous machine caused by stator slot effect

Long,

Song

2024

IET Electric Power Appl

View full text Add to dashboard Cite

To improve the machine torque density, this paper proposes a magnet‐surrounded permanent magnet synchronous machine (MSPMSM). As the critical material of MSPMSM, the permanent magnet (PM) will produce significant eddy current loss under the action of eddy current electromotive force. Therefore, it is essential to investigate the change in PM eddy current loss and methods to suppress it. To solve the above problems, a simplified analytical calculation model for the eddy current loss of PMs caused by stator slotting is proposed. The distribution law of eddy current loss of PMs caused by stator slotting is studied. The concept of influence depth is proposed to solve the problem of unclear correspondence between the groove depth on the PM surface and the eddy current loss of PMs. The calculation results of the influence depth are used to guide the single‐side partial grooving method to reduce the eddy current loss of PMs. In addition, a comparative analysis is conducted on the anti‐demagnetisation ability of PMs before and after MSPMSM optimisation. Finally, the experiment verifies the correctness of the analytical calculation and the high torque density of the MSPMSM.

show abstract

An Analytical Method for Predicting 3-D Eddy Current Loss in Permanent Magnet Machines Based on Generalized Image Theory

Abstract: This is a repository copy of An analytical method for predicting 3D eddy current loss in permanent magnet machines based on generalized image theory.

Cited by 31 publications

References 34 publications

Computationally Efficient 3-D Eddy Current Loss Prediction in Magnets of Interior Permanent Magnet Machines

Computationally Efficient 3-D Eddy Current Loss Prediction in Magnets of Interior Permanent Magnet Machines

Investigation of Permanent Magnet Demagnetization in Synchronous Machines during Multiple Short-Circuit Fault Conditions

Analytical modelling and analysis of magnet eddy current loss in magnet‐surrounded permanent magnet synchronous machine caused by stator slot effect

Contact Info

Product

Resources

About