Abstract
A simplified extended Kalman filter (EKF) based sensorless direct torque control technique for a permanent magnet brushless AC drive is proposed. Its performance is compared with that obtained with other sensorless methods for estimating the rotor speed and position from a stator flux-linkage. Since the EKF has an inherently adaptive filtering capability and does not introduce phase delay, the technique provides better speed estimates. In addition, the technique is easy to implement and requires minimal computation.
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Yong Liu received the B.Eng and M.Sc. degrees in electrical engineering from Zhejiang University, Hangzhou, China, in 1999 and 2002, respectively.
Since 2002, he has been with the Department of Electronic and Electrical Engineering, the University of Sheffield, Sheffield, U.K., where he is currently a PhD student. His research interests include control of electrical drives, in particular, the direct torque control of permanent magnetic brushless motors.
Ziqiang Zhu received the B.Eng. and M.Sc. degrees from Zhejiang University, Hangzhou, China, in 1982 and 1984, respectively, and was awarded the Ph.D. by the University of Sheffield, Sheffield, UK, in 1991, all in electrical and electronic engineering.
From 1984 to 1988 he lectured in the Department of Electrical Engineering at Zhejiang University. Since 1988, he has been with the University of Sheffield, where he is currently Professor of Electronic and Electrical Engineering. His current major research interests include applications, control, and design of permanent magnet machines and drives.
David Howe received the B.Tech and M.Sc. degrees from the University of Bradford, in 1966 and 1967, respectively, and a Ph.D. from the University of Southampton in 1974, all in electrical power engineering.
He has held academic posts at Brunel and Southampton Universities, and spent a period in industry with NEI Parsons Ltd working on electromagnetic problems related to turbo-generators. He is currently Professor of Electrical Engineering at the University of Sheffield, where he heads the Electrical Machines and Drives Research Group. His research activities span all facets of controlled electrical drive systems, with particular emphasis on permanent magnet excited machines. Prof. Howe is a Fellow of the Royal Academy of Engineering and a Fellow of the IEE, UK.
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Liu, Y., Zhu, Z. & Howe, D. Simplified EKF based sensorless direct torque control of permanent magnet brushless AC drives. Int J Automat Comput 1, 35–41 (2004). https://doi.org/10.1007/s11633-004-0035-4
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DOI: https://doi.org/10.1007/s11633-004-0035-4