Winding factor calculation for analysis of back EMF waveform in air-core permanent magnet linear synchronous motors

This study presents an analytical method for winding factor calculation and back electromotive force (EMF) prediction in air-core permanent magnet linear synchronous motors. In the proposed method, the voltage on each coil of a phase winding is calculated by adding the voltage induced in individual conductors considering a phase shift proportional to the conductor diameter. The proposed method can be used to find back EMF waveform of air-core linear motors with any winding configuration in terms of dimensional specifications of magnet track and winding assembly. Once the back EMF equation is obtained, it can be used to predict the thrust of the motor.The results of the proposed analytical model are compared with finite element analysis results for three different motors to verify the validity of the proposed modelling method. In order to investigate the effect of simplifying assumptions in model derivation, experimental back EMF result on a three-phase eight-pole motor is presented and compared with the proposed analytical model.

[1]  D. Howe,et al.  Armature reaction field and inductances of tubular modular permanent magnet machines , 2005 .

[2]  A.H. Isfahani,et al.  Enhanced Modeling of Linear Permanent-Magnet Synchronous Motors , 2007, IEEE Transactions on Magnetics.

[3]  Gyu-Hong Kang,et al.  A novel design of an air-core type permanent magnet linear brushless motor by space harmonics field analysis , 2001 .

[4]  A. Shoulaie,et al.  Analysis and Design of Magnetic Pole Shape in Linear Permanent-Magnet Machine , 2010, IEEE Transactions on Magnetics.

[5]  S.M. Jang,et al.  Design and Bidirectional Motion Control of Double-side LSM with Slotless Iron-Cored Stator and PM mover Using Control Parameters Estimation and Discrete System Modeling , 2006, Conference Record of the 2006 IEEE Industry Applications Conference Forty-First IAS Annual Meeting.

[6]  N. Chayopitak,et al.  Performance Assessment of Air-Core Linear Permanent-Magnet Synchronous Motors , 2008, IEEE Transactions on Magnetics.

[7]  S.J.O. Proverbs,et al.  Theory and performance of segmental secondary linear hybrid synchronous motors , 2010 .

[8]  M.A. Rahman,et al.  Using Modular Poles for Shape Optimization of Flux Density Distribution in Permanent-Magnet Machines , 2008, IEEE Transactions on Magnetics.

[9]  M. Kamper.  Comparison of linear permanent magnet machine with overlapping and non-overlapping air-cored stator windings , 2008 .

[10]  Kais Atallah,et al.  A Linear Permanent-Magnet Motor for Active Vehicle Suspension , 2011, IEEE Transactions on Vehicular Technology.

[11]  A. Onat,et al.  Modeling of Air Core Permanent-Magnet Linear Motors With a Simplified Nonlinear Magnetic Analysis , 2011, IEEE Transactions on Magnetics.

[12]  Sadegh Vaez-Zadeh,et al.  Multiobjective design optimization of air-core linear permanent-magnet synchronous motors for improved thrust and low magnet consumption , 2006, IEEE Transactions on Magnetics.

[13]  Sadegh Vaez-Zadeh,et al.  Design optimization of a linear permanent magnet synchronous motor for extra low force pulsations , 2007 .

[14]  R. Hanitsch,et al.  Development and control of a prototype permanent-magnet DC linear motor , 2007 .

[15]  M. E. Williams,et al.  Design and analysis framework for linear permanent magnet machines , 1994, Proceedings of 1994 IEEE Industry Applications Society Annual Meeting.

[16]  Hany M. Hasanien,et al.  Design development of permanent magnet excitation transverse flux linear motor with inner mover type , 2010 .

[17]  J.P. Hong,et al.  Static characteristics of linear BLDC motor using equivalent magnetic circuit and finite element method , 2004, IEEE Transactions on Magnetics.

[18]  N. Bianchi.  Analytical field computation of a tubular permanent-magnet linear motor , 2000 .

[19]  C. Sadarangani,et al.  Winding factors and Joule losses of permanent magnet machines with concentrated windings , 2003, IEEE International Electric Machines and Drives Conference, 2003. IEMDC'03..

[20]  B. V. Jayawant,et al.  Permanent-magnet linear eddy-current brake with a non-magnetic reaction plate , 1999 .

[21]  M Gabsi,et al.  Three-Dimensional Analytical Modeling of a Permanent-Magnet Linear Actuator With Circular Magnets , 2010, IEEE Transactions on Magnetics.

[22]  Sadegh Vaez-Zadeh,et al.  Performance improvement of permanent magnet machines by modular poles , 2009 .

[23]  B. Stumberger,et al.  Analytical Analysis of Magnetic Field and Force Calculation in a Slotless-Type Permanent Magnet Linear Synchronous Machine; Verification with Numerical Analysis , 2007, 2007 IEEE International Electric Machines & Drives Conference.

[24]  Jiabin Wang,et al.  Design Optimization of Short-Stroke Single-Phase Tubular Permanent-Magnet Motor for Refrigeration Applications , 2010, IEEE Transactions on Industrial Electronics.

[25]  A.H. Isfahani,et al.  Analytical Framework for Thrust Enhancement in Permanent-Magnet (PM) Linear Synchronous Motors With Segmented PM Poles , 2010, IEEE Transactions on Magnetics.