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Speed Estimator (speed + estimator)

Distribution by Scientific Domains

Engineering	100%

Selected Abstracts

Tuning and parameter variation effects in MRAS based speed estimator for sensorless vector controlled induction motor drives

EUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 3 2002
M. Wang
A frequently applied method of speed-sensorless rotor flux oriented control of induction machines relies on utilisation of model reference adaptive system (MRAS) based speed estimation, where the outputs of the reference and the adjustable model are selected as rotor flux space phasors. Accuracy of the method heavily depends on correct setting of the machine parameters and adjustment of the filter and Pl controller parameters within the estimator. The paper at first describes tuning of various parameters of the estimator, using purely experimental data. The speed estimator is operated in parallel with a commercially available rotor flux oriented induction motor drive with speed sensor and sampled stator voltages and currents are used to tune induction motor parameters, various filters and the Pl controller within the estimator. The procedure is described and illustrated using a comparison between the measured actual speed response during acceleration transients and the corresponding speed estimate obtained from the speed estimator. In the second part of the paper, speed estimation error that will take place in the base speed region due to incorrect setting and/or variation of the parameters of the machine (stator resistance, rotor resistance and magnetising inductance) within the speed estimator is assessed using experimentally recorded data. The experimental results are found to be in very good agreement with previously published theoretical results. [source]

Robust speed estimation and control of an induction motor drive based on artificial neural networks

INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 5 2008
Oscar Barambones
Abstract In this paper, a speed estimation and control scheme of an induction motor drive based on an indirect field-oriented control is presented. On one hand, a rotor speed estimator based on an artificial neural network is proposed, and on the other hand, a control strategy based on the sliding-mode controller type is proposed. The stability analysis of the presented control scheme under parameter uncertainties and load disturbances is provided using the Lyapunov stability theory. Finally, simulated results show that the presented controller with the proposed observer provides high-performance dynamic characteristics and that this scheme is robust with respect to plant parameter variations and external load disturbances. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Adaptive sensorless robust control of AC drives based on sliding mode control theory

INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 9 2007
O. Barambones
Abstract This paper focuses in the design of a new adaptive sensorless robust control to improve the trajectory tracking performance of induction motors. The proposed design employs the so-called vector (or field oriented) control theory for the induction motor drives, being the designed control law based on an integral sliding-mode algorithm that overcomes the system uncertainties. This sliding-mode control law incorporates an adaptive switching gain in order to avoid the need of calculating an upper limit for the system uncertainties. The proposed design also includes a new method in order to estimate the rotor speed. In this method, the rotor speed estimation error is presented as a first-order simple function based on the difference between the real stator currents and the estimated stator currents. The stability analysis of the proposed controller under parameter uncertainties and load disturbances is provided using the Lyapunov stability theory. The simulated results show, on the one hand that the proposed controller with the proposed rotor speed estimator provides high-performance dynamic characteristics, and on the other hand that this scheme is robust with respect to plant parameter variations and external load disturbances. Finally, experimental results show the performance of the proposed control scheme. Copyright © 2006 John Wiley & Sons, Ltd. [source]