Rotor Position Tracking Research Articles

Adaptive control of induction motor systems despite rotor resistance uncertainty

We present an adaptive, partial-state feedback, position tracking controller for the full-order, nonlinear dynamic model representing an induction motor actuating a mechanical subsystem. The proposed controller compensates for uncertainty in the form of the rotor resistance parameter and all of the mechanical subsystem parameters, while yielding asymptotic rotor position tracking. The proposed controller does not require measurement of rotor flux or rotor current; however, it does exhibit a singularity when the magnitude of the estimated rotor flux is zero. Simulation results are provided to verify the effectiveness of the approach. Copyright © 1996 Elsevier Science Ltd.

Nonlinear control of active magnetic bearings: a backstepping approach

In this paper, the authors utilize a nonlinear model of a planar rotor disk, active magnetic bearing system to develop a nonlinear controller for a full-order electromechanical system. The controller requires measurement of the rotor position, rotor velocity, and stator current and achieves global exponential rotor position tracking. Simulations are provided to illustrate the performance of the controller.

Position tracking control of an induction motor via partial state feedback

This paper presents a rotor position tracking controller for an induction motor driving a robotic load. Using the nonlinear model of the induction motor and a nonlinear observer, local exponential rotor position tracking is obtained. The control only requires measurements of rotor position and stator current, while utilizing exact-model knowledge. Experimental results are included to illustrate the effectiveness of the proposed controller.

A Globally Stable Discrete-Time Controller for Current-Fed Induction Motors

In this short paper we present a discrete-time field oriented controller (FOC) for current-fed induction motors which insures global asymptotic rotor position (or velocity) tracking. To the best of our knowledge, this is the first time such a result is rigourously established for a controller implemented in discrete-time. As expected in a discrete-time controller, an unavoidable condition relating the sampling rate with the rate of change of the references is imposed. This condition disappears as the sampling rate goes to zero. Interestingly enough, the condition also reflects the well known fact that to avoid magnetic saturation the flux norm must be increased when the machine is requested to deliver large torques. One important feature of our scheme is that it is obtained via a slight -but essential- modification to a first difference approximation of the classical indirect FOC, hence its additional computational burden is negligible.