Modeling and Parametric Design of Permanent-Magnet AC Machines Using Computationally Efficient Finite-Element Analysis

Computationally efficient finite-element analysis (FEA) (CE-FEA) fully exploits the symmetries of electric and magnetic circuits of sine-wave current-regulated synchronous machines and yields substantial savings of computational efforts. Motor performance is evaluated through Fourier analysis and a minimum number of magnetostatic solutions. The major steady-state performance indices (average torque, ripple and cogging torque, back-electromotive-force waveforms, and core losses) are satisfactorily estimated as compared with the results of detailed time-stepping (transient) FEA. In this paper, the CE-FEA method is presented and applied to a parametric design study for an interior-permanent-magnet machine. Significant reduction of simulation times is achieved (approximately two orders of magnitude), permitting a comprehensive search of large design spaces for optimization purposes. In this case study, the influence of three design variables, namely, stator tooth width, pole arc, and slot opening, on three performance indices, namely, average torque, efficiency, and full-load torque ripple, is examined, and design trends are derived. One hundred candidate designs are simulated in less than 20 minutes on a state-of-the-art workstation.

[1]  Thomas M. Jahns,et al.  A saturating lumped-parameter model for an interior PM synchronous machine , 2002 .

[2]  Dan M. Ionel,et al.  Ultra-fast finite element analysis of brushless PM machines based on space-time transformations , 2009, 2009 IEEE International Electric Machines and Drives Conference.

[3]  Maarten J. Kamper,et al.  Optimal Torque Control of Synchronous Machines Based on Finite-Element Analysis , 2010, IEEE Transactions on Industrial Electronics.

[4]  Dan M. Ionel.  High-efficiency variable-speed electric motor drive technologies for energy savings in the US residential sector , 2010, 2010 12th International Conference on Optimization of Electrical and Electronic Equipment.

[5]  Kalyanmoy Deb,et al.  Multi-objective optimization using evolutionary algorithms , 2001, Wiley-Interscience series in systems and optimization.

[6]  Massimo Barcaro,et al.  Average and oscillating torque determination in fractional-slot PM motors , 2010, The XIX International Conference on Electrical Machines - ICEM 2010.

[7]  Ewen Ritchie,et al.  A magnetic equivalent circuit approach for predicting PM motor performance , 1997, IAS '97. Conference Record of the 1997 IEEE Industry Applications Conference Thirty-Second IAS Annual Meeting.

[8]  Dimitri Torregrossa,et al.  Prediction of Acoustic Noise and Torque Pulsation in PM Synchronous Machines With Static Eccentricity and Partial Demagnetization Using Field Reconstruction Method , 2012, IEEE Transactions on Industrial Electronics.

[9]  R. Storn,et al.  Differential Evolution: A Practical Approach to Global Optimization (Natural Computing Series) , 2005 .

[10]  Z. Q. Zhu,et al.  Comparison of analytical models for predicting cogging torque in surface-mounted PM machines , 2010, The XIX International Conference on Electrical Machines - ICEM 2010.

[11]  Min-Fu Hsieh,et al.  A Review of the Design Issues and Techniques for Radial-Flux Brushless Surface and Internal Rare-Earth Permanent-Magnet Motors , 2011, IEEE Transactions on Industrial Electronics.

[12]  David G. Dorrell.  Combined Thermal and Electromagnetic Analysis of Permanent-Magnet and Induction Machines to Aid Calculation , 2008, IEEE Transactions on Industrial Electronics.

[13]  T.J.E. Miller,et al.  Assessment of torque components in brushless permanent magnet machines through numerical analysis of the electromagnetic field , 2004, Conference Record of the 2004 IEEE Industry Applications Conference, 2004. 39th IAS Annual Meeting..

[14]  F. Fouad,et al.  Magnetic Field Modeling of Permanent Magnet Type Electronically Operated Synchronous Machines Using Finite Elements , 1981, IEEE Transactions on Power Apparatus and Systems.

[15]  Jere Kolehmainen.  Optimal Dovetail Permanent Magnet Rotor Solutions for Various Pole Numbers , 2010, IEEE Transactions on Industrial Electronics.

[16]  D.M. Ionel,et al.  Computation of Core Losses in Electrical Machines Using Improved Models for Laminated Steel , 2006, IEEE Transactions on Industry Applications.

[17]  Dan M. Ionel,et al.  Finite element surrogate model for electric machines with revolving field — application to IPM motors , 2009 .

[18]  J. Eastham,et al.  Finite element analysis of brushless DC motors for flux weakening operation , 1996 .

[19]  S. J. Salon,et al.  Finite element analysis of electrical machines , 1995 .

[20]  R. Wang,et al.  Computation of load performance and other parameters of extra high speed modified Lundell alternators from 3D-FE magnetic field solutions , 1992 .

[21]  Andrea Cavagnino,et al.  Evolution and Modern Approaches for Thermal Analysis of Electrical Machines , 2009, IEEE Transactions on Industrial Electronics.

[22]  D M Ionel,et al.  Ultrafast Finite-Element Analysis of Brushless PM Machines Based on Space–Time Transformations , 2011, IEEE Transactions on Industry Applications.

[23]  T. Lipo,et al.  Analytical calculation of magnetic field distribution in the slotted air gap of a surface permanent-magnet motor using complex relative air-gap permeance , 2006, IEEE Transactions on Magnetics.

[24]  Dan M. Ionel,et al.  Modeling and design optimization of PM AC machines using computationally efficient - finite element analysis , 2010, 2010 IEEE Energy Conversion Congress and Exposition.

[25]  Z.J. Liu,et al.  Accurate Prediction of Magnetic Field and Magnetic Forces in Permanent Magnet Motors Using an Analytical Solution , 2008, IEEE Transactions on Energy Conversion.