Implementation of an improved low‑resolution encoder‑based speed and rotor flux estimation strategy for induction motors in the wide‑speed range

An induction motor (IM) drive system with low-resolution encoders has to make a compromise between cost and performance, which is suitable for industrial electric vehicles, including electric forklifts, and electric lifts. However, the inaccurate and delayed position signals from low-resolution encoders lead to torque ripple and oscillations in rotational speed, especially in the low-speed range. To address these problems, this paper proposes an improved low-resolution encoder-based speed and rotor flux estimation strategy. The hybrid speed observer is designed to estimate the rotational speed smoothly and accurately. Meanwhile, an improved reduced-order flux observer with an adaptive gain is designed to meet the control performance requirement in the wide-speed range. The improved low-resolution encoder-based speed and rotor flux estimation strategy can meet the requirements of a high output torque at extremely low or zero speed, and full-power operation in the high-speed range. A 680 W IM test platform is built, and experimental results verify the effectiveness and correctness of the improved low-resolution encoder-based speed and rotor flux estimation strategy.

Statistics

Show / Hide Statistics

Cumulative Counts from September 30th, 2019
Multiple requests among the same browser session are counted as one view. If you mouse over a chart, the values of data points will be shown.

Cite this article

[IEEE Style]

H. Dan, Y. Ma, P. Zeng, Y. Sun, M. Rivera, P. Wheeler, "Implementation of an improved low‑resolution encoder‑based speed and rotor flux estimation strategy for induction motors in the wide‑speed range," Journal of Power Electronics, vol. 26, no. 1, pp. 88-100, 2026. DOI: 10.1007/s43236-025-01069-3.

[ACM Style]

Hanbing Dan, Yongjian Ma, Peng Zeng, Yao Sun, Marco Rivera, and Patrick Wheeler. 2026. Implementation of an improved low‑resolution encoder‑based speed and rotor flux estimation strategy for induction motors in the wide‑speed range. Journal of Power Electronics, 26, 1, (2026), 88-100. DOI: 10.1007/s43236-025-01069-3.