Wide Speed Range Sensorless Operation of Brushless Permanent-Magnet Motor Using Flux Linkage Increment
August 3 @ 4:10 pm - 4:35 pm
Brushless permanent-magnet (PM) machines offer high efficiency, high-power density, and low maintenance. However, they require the use of an electronic drive to synchronise the current waveforms to the rotor position. Typically, this is achieved through use of external position sensors mounted to the motor shaft. To reduce costs and increase reliability, it is desirable to eliminate these external sensors. Existing back-electromotive force (EMF) and flux linkage-based indirect rotor position detection methods have limitations, specifically poor position accuracy and inability to operate at low as well as at high speed. However, practical motor drives require precise operation over a wide speed range, which widens the application areas while increasing reliability compared to direct position sensor-based drives. This seminar presents a method that uses terminal voltage measurements to estimate the flux linkage increment and determine the rotor position, while avoiding the accumulated position error that is a characteristic of flux linkage-based techniques. Common problems associated with the practical implementation, such as low-pass filter delay, integrator offset error, and noise sensitivity at low speed will be discussed. Experimental data will be presented that verifies both the operational robustness and position accuracy of the method.
Gabriel Haines (S’15) received the B.E. degree (with honours) in electrical and electronic engineering from The University of Adelaide, Adelaide, Australia, in 2012, where he is currently working toward the Ph.D. degree. His research interests include sensorless motor control, motor modelling, power electronics, and energy storage systems.