Real-Time Speed and Position Estimation Using Rotor Slot Harmonics

It is well known that slotting harmonics exist in most of the electrical machines. So far, these harmonics are mainly identified using spectral estimation techniques. However, this approach requires long sampling and computation periods. In this study, a novel speed and position estimation method based on identification of rotor slot harmonics (RSH) that does not require any kind of spectral analysis is proposed. The required information is extracted by demodulating the information available in an external search coil (or in phase current). The algorithm used for this purpose is fast and can be applied within a typical control cycle of a vector controlled drive algorithm. In the application of the method here, higher order RSH have been utilized. In this manner, the position estimation resolution increases and also possible effect of harmonics stemming from other sources are avoided. The approach is explained in the paper and illustrated with experimental results.


Speed position estimation by demodulating rotor slot harmonics
Keysan, Ozan (2011-11-11)
It is well known that slotting harmonics exist in most of the electrical machines. These harmonics may supply valuable information for condition monitoring of bearings, windings or rotor bars. Utilization of these harmonics for rotor speed and position estimation is limited mainly due to long sampling periods required by spectral estimation techniques. In this study, a novel speed and position estimation method is proposed that does not need any kind of spectral estimation. In this approach extracting the r...
Higher Order Rotor Slot Harmonics for Rotor Speed & Position Estimation
Keysan, Ozan; Ertan, Hulusi Bülent (2010-05-21)
Air-gap flux of all electrical machines contains harmonics. Some of these harmonics stem from rotor slotting of the machine. These harmonics can be utilized for control or diagnostic purposes. In the literature, rotor slot harmonics are mostly utilized for condition monitoring. There is also some research utilizing them for rotor speed estimation. However, it is observed that in the existing work spectral analysis techniques are employed which require long samples of data and in this from they are not suita...
Implementation issues of real time position estimation for induction motors using rotor slot harmonics
Ertan, Hulusi Bülent; Keysan, Ozan (2013-11-15)
In this paper, an approach to identify rotor slot harmonics, from motor currents or from induced voltage in an internal or external search coil voltage is described. The importance of this method is that instantaneous value of the rotor slot harmonics can be determined in real time. In this manner, it is possible to determine motor speed or rotor position of a motor in a short enough time, for use in vector control. This method is independent of motor parameters. Using this method an additional feedback bec...
Vibration Analysis of a Simply Supported PCB with a Component-An Analytical Approach
Aytekin, Banu; Ozguven, Nevzat (2008-12-12)
It is a well known fact that vibration is one of the most important loading condition in electronic systems. This study deals with dynamic analysis of a printed circuit board (PCB) with a component on it under vibratory loading. The objective of the study is to develop an analytical model for common PCB configurations and electronic components on them in order to predict dynamics of the assembly under vibratory loading, and thus to study the effects of component location. As an application, in this paper an...
Efficiency Control of Single Phase Induction Motor Drive
Asadabadi, Y. Abdellahi; Markadeh, Gh. R. Arab; Soltani, J.; Heidar, R. (2011-09-10)
Single-phase induction motors are widely used in home appliances and industrial control. The multispeed operation and multipurpose operation are provided by controlling the speed of these motors. This paper presents variable-frequency motor drive system implemented by PWAI voltage source inverter, to improve a single-phase induction machine (SIM) efficiency.
Citation Formats
O. Keysan and H. B. Ertan, “Real-Time Speed and Position Estimation Using Rotor Slot Harmonics,” IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS, pp. 899–908, 2013, Accessed: 00, 2020. [Online]. Available: