SPMSM Design Considerations for Initial Position and Magnet Polarity Estimation using Carrier Signal Injection

Initial position and magnet polarity estimation is required for smooth start-up of permanent magnet synchronous machines. The signal-to-noise ratio of the salient signals used for initial position and magnet polarity estimation depends on the machine design and affects the overall performance of the estimation technique. This paper investigates the design of a ring-magnet, surface permanent magnet synchronous machine to maximize the signal-to-noise ratio of the position and polarity signals without compromising the machine performance. Since the rotor geometry is fixed given the ring-magnet, the effect of the stator tooth tip geometry on the saliency signals is evaluated using finite element analysis. By adding a bridge between the stator teeth, the magnitude of the polarity-based signal can be increased significantly. A coupled simulation verifies the implementation of the improved initial position and magnet polarity estimation based on modified machine design.

[1]  R. Lorenz,et al.  Using multiple saliencies for the estimation of flux, position, and velocity in AC machines , 1997, IAS '97. Conference Record of the 1997 IEEE Industry Applications Conference Thirty-Second IAS Annual Meeting.

[2]  Robert D. Lorenz,et al.  Using multiple saliencies for the estimation of flux, position, and velocity in AC machines , 1997 .

[3]  R. Wrobel,et al.  Design Considerations for Permanent Magnet Brushless Machines for Zero-Speed Sensorless Position Estimation , 2006, Conference Record of the 2006 IEEE Industry Applications Conference Forty-First IAS Annual Meeting.

[4]  M. Schroedl,et al.  Sensorless control of AC machines at low speed and standstill based on the "INFORM" method , 1996, IAS '96. Conference Record of the 1996 IEEE Industry Applications Conference Thirty-First IAS Annual Meeting.

[5]  R.D. Lorenz,et al.  Implementation issues for fast initial position and magnet polarity identification of PM synchronous machines with near zero saliency , 2005, 2005 European Conference on Power Electronics and Applications.

[6]  M. Sanada,et al.  Influence of Rotor Configuration on Sensorless Control for Interior Permanent Magnet Synchronous Motors , 2006, Conference Record of the 2006 IEEE Industry Applications Conference Forty-First IAS Annual Meeting.

[7]  Jung-Ik Ha,et al.  Sensorless rotor position estimation of an interior permanent-magnet motor from initial states , 2003 .

[8]  Thomas M. Jahns,et al.  A novel method for initial rotor position estimation for IPM synchronous machine drives , 2003 .

[9]  Robert D. Lorenz,et al.  Transducerless position and velocity estimation in induction and salient AC machines , 1994, Proceedings of 1994 IEEE Industry Applications Society Annual Meeting.

[10]  K. Akatsu,et al.  Comparing Coupled Analysis With Experimental Results for an Interior PM Machine , 2009, IEEE Transactions on Industry Applications.

[11]  Toshihiko Noguchi,et al.  Initial rotor position estimation method of sensorless PM synchronous motor with no sensitivity to armature resistance , 1998, IEEE Trans. Ind. Electron..

[12]  Kaushik Rajashekara,et al.  Sensorless control of AC motor drives : speed and position sensorless operation , 1996 .

[13]  Seung-Ki Sul,et al.  Advantages of Inset PM Machines for Zero-Speed Sensorless Position Detection , 2008, IEEE Transactions on Industry Applications.

[14]  Hirofumi Akagi,et al.  An approach to real-time position estimation at zero and low speed for a PM motor based on saliency , 1996, IAS '96. Conference Record of the 1996 IEEE Industry Applications Conference Thirty-First IAS Annual Meeting.