Rotor slot harmonics based induction machine speed estimation

Some of the most common types of electrical drives imply the use of induction machines as their integral part. Making use of the economically most viable solution, the researchers have always strived to increase the reliability of such drives, while constantly trying to decrease maintenance cost. On the other hand, including a large number of sensors, required by the novel control techniques, usually have the opposite effect. Therefore, a logical sequence of events shifted the research focus to sensorless control strategies, based on the advanced algorithm for speed estimation. As the more reliable concept, speed estimation based on magnetic anisotropy is used for high performance drives. In addition, these algorithms are used for parameter adaptation mechanisms for standard model based speed estimation. This paper will present the possibility of speed estimation based on the detection of rotor slot harmonics. The experimental verification will be performed on an advanced laboratory prototype for control of electrical drives, developed at the Faculty of Technical Sciences.