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Overview of AC Motor Sensorless Algorithms: a Unified Perspective
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  • Jiahao Chen ,
  • Jie Mei ,
  • Yuefei Zuo ,
  • Jingwei Zhu ,
  • Xin Yuan ,
  • Christopher H. T. Lee ,
  • Frede Blaabjerg
Jiahao Chen
Nanyang Technological University, Nanyang Technological University, Nanyang Technological University

Corresponding Author:[email protected]

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Yuefei Zuo
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Jingwei Zhu
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Christopher H. T. Lee
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Frede Blaabjerg
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This paper reviews sensorless algorithms for both induction motors and permanent magnet motors using the active flux model, such that any design applicable for non-salient pole ac motors can also be included in the review framework. The proposed review framework classifies all sensorless algorithms following a five-layer hierarchy abbreviated as O-I-M-A-I, resulting in four main categories as i) inherently sensorless position estimation, ii) non-inherently sensorless position estimation, iii) post-position-estimation speed estimation, and iv) speed estimation for indirect field orientation. Various ac motor models are derived by assuming a constant active flux amplitude, based on which seven generic sensorless algorithms are summarized in a tutorial. Recommendations are made for sensorless drive designers to begin with inherently sensorless method such that the two-way coupling between position estimation and speed estimation is avoided. Finally, classical induction motor model results from time-varying active flux amplitude and slip relation, for which a state transformation is recommended for achieving global stability.
Feb 2023Published in IEEE Journal of Emerging and Selected Topics in Power Electronics volume 11 issue 1 on pages 915-931. 10.1109/JESTPE.2022.3194520