Microstructure Role in Permanent Magnet Eddy Current Losses

The impact of granular microstructure on permanent magnets on eddy current losses is investigated. A numerical homogenization procedure for electrical conductivity is defined. Then, an approximated simple analytical model for the homogenized conductivity able to capture the main features of the geometrical and material dependences is derived. Finally, analytic calculations of eddy current losses are given, and the two asymptotic expressions for losses in the stationary conduction limit and advanced skin effect limit are derived and discussed.

[1]  T. Schrefl,et al.  Grain-size dependent demagnetizing factors in permanent magnets , 2014, 1603.08239.

[2]  Isaak D. Mayergoyz,et al.  Iterative solution of 3D eddy current problems , 1993 .

[3]  Hongwen He,et al.  Efficiency Decrease Estimation of a Permanent Magnet Synchronous Machine with Demagnetization Faults , 2017 .

[4]  Amr A. Adly,et al.  The impact of demagnetization on the feasibility of permanent magnet synchronous motors in industry applications , 2019, Journal of advanced research.

[5]  R. Quey,et al.  Large-scale 3D random polycrystals for the finite element method: Generation, meshing and remeshing , 2011 .

[6]  A. Kremser,et al.  Eddy current loss analysis in permanent magnets of synchronous machines , 2016, 2016 6th International Electric Drives Production Conference (EDPC).

[7]  K. Hameyer,et al.  Automated sizing of permanent magnet synchronous machines with respect to electromagnetic and thermal aspects , 2008, 2008 18th International Conference on Electrical Machines.

[8]  Thomas Schrefl,et al.  Understanding the microstructure and coercivity of high performance NdFeB-based magnets , 2012 .

[9]  Guglielmo Rubinacci,et al.  Formulation of eddy current problem , 1990 .

[10]  Isaak D. Mayergoyz,et al.  Iterative Solution Of 3-d Eddy Current Problems , 1993 .

[11]  Antonios G. Kladas,et al.  Permanent-Magnet Shape Optimization Effects on Synchronous Motor Performance , 2011, IEEE Transactions on Industrial Electronics.

[12]  Yongxiang Yang,et al.  REE Recovery from End-of-Life NdFeB Permanent Magnet Scrap: A Critical Review , 2017, Journal of Sustainable Metallurgy.

[13]  H. Sepehri-Amin,et al.  Coercivity and its thermal stability of Nd Fe B hot-deformed magnets enhanced by the eutectic grain boundary diffusion process , 2018, Acta Materialia.

[14]  F. Dubas,et al.  Permanent-Magnet Eddy-Current Losses: A Global Revision of Calculation and Analysis , 2019, Mathematical and Computational Applications.

[15]  Lutz Gross,et al.  PDE-based geophysical modelling using finite elements: examples from 3D resistivity and 2D magnetotellurics , 2016 .

[16]  O. Solgaard.  Electromagnetic Fields and Energy , 2009 .

[17]  Stephane Clenet,et al.  Permanent magnet modelling for dynamic applications , 2008 .

[18]  Xavier Jannot,et al.  Analytical calculation of rotor magnet eddy-current losses for high speed IPMSM , 2010, The XIX International Conference on Electrical Machines - ICEM 2010.