Encoder-Motor Misalignment Compensation for Closed-Loop Hybrid Stepper Motor Control

  • Stefano RicciEmail author
  • Valentino Meacci
  • Dario Russo
  • Riccardo Matera
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 573)


Field-Oriented Control (FOC) of hybrid stepper motors allows high performance in motor movements. In FOC, the shaft position is tracked through an encoder (or a similar device), and the stator magnetic field orientation is continuously adjusted to maintain the desired load angle, i.e. the phase between the magnetic fields produced by the stator windings and the rotor magnet. Unfortunately, measuring the load angle with high accuracy is not trivial. For example, in a typical 200 step/turn motor, the electro-mechanical configuration repeats every 7.8°, and a 5% load angle accuracy requires a 5/50 = 0.1% absolute accuracy in the alignment among motor windings and encoder and/or their coupling. When this is not achieved, torque and velocity are affected by oscillations. In this paper a simple solution is proposed where the misalignment errors are mapped with an open-loop motor run, and then compensated during the normal FOC employment. Experiments with a 1.1 Nm, 2-phase, 200-step/turn hybrid stepper motor show how the proposed method reduces the velocity oscillations in a constant torque condition.



This work is part of the MIPEC project (CUP 4421.02102014.072000051), funded by the Tuscany Region government through the FAR-FAS 2014 program. Authors thank Microtest srl (Altopascio, Italy) and the DIEF of the University of Florence (Italy) for their support.


  1. 1.
    Athani, V.V.: Stepper Motors: Fundamentals, Applications and Design, New Age Inpernational (P) Ltd, New Delhi, India, reprint. ISBN 978-8122410068 (2005)Google Scholar
  2. 2.
    Gaan, D.R., Kumar, M., Sudhakar, S.: Real-time precise position tracking with stepper motor using frequency modulation based microstepping. IEEE J. Ind. Appl. 54(1), 693–701 (2018). Scholar
  3. 3.
    Le, K.M., Hoang, H.V., Jeon, J.W.: An advanced closed-loop control to improve the performance of hybrid stepper motors. IEEE T. Power Electr. 32(9), 7244–7255 (2016). Scholar
  4. 4.
    Kim, W., Yang, C., Chung, C.C.: Design and implementation of simple field-oriented control for permanent magnet stepper motors without DQ transformation. IEEE T Magn. 47(10), 4231–4234 (2011). Scholar
  5. 5.
    Ricci, S., Meacci, V., Birkhofer, B., Wiklund, J.: FPGA-based system for in-line measurement of velocity profiles of fluids in industrial pipe flow. IEEE T Ind. Electron. 64(5), 3997–4005 (2017). Scholar
  6. 6.
    Ricci, S., Liard, M., Birkhofer, B., Lootens, D., Brühwiler, A., Tortoli, P.: Embedded doppler system for industrial in-line rheometry. IEEE Trans. Ultrason. Ferroelect. Freq. Contr. 59(7), 1395–1401 (2012). Scholar
  7. 7.
    Ricci, S., Meacci, V.: Simple torque control method for hybrid stepper motors implemented in FPGA. Electr. 7(10), 242 (2018). Scholar
  8. 8.
    Intel: Intel MAX10 FPGA Device Datasheet. M10-DATASHEET, December 2017.
  9. 9.
    STMicroelectronics: PowerStep01 Datasheet. DocID025022 Rev 6, November 2017.

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Stefano Ricci
    • 1
    Email author
  • Valentino Meacci
    • 1
  • Dario Russo
    • 1
  • Riccardo Matera
    • 1
  1. 1.Information Engineering DepartmentUniversity of FlorenceFlorenceItaly

Personalised recommendations