Developing Induction Motor State Observers with Increased Robustness

Tadeusz Białoń,Marian Pasko,Roman Niestrój

doi:10.3390/en13205487

Abstract

This paper presents the results of recently conducted research on Luenberger observers with non-proportional feedbacks. The observers are applied for the reconstruction of magnetic fluxes of an induction motor. Structures of the observers known from the control theory are presented. These are a proportional observer, a proportional-integral observer, a modified integral observer, and an observer with additional integrators. The practical application of some of these observers requires modifications to their structures. In the paper, the simulation results for all mentioned types of observers are presented. The simulations are performed with a Scilab-Xcos model which is attached to this paper. The problem of gains selection of the observers is discussed. Gains are selected with the described optimization method based on a genetic algorithm. A Scilab file launching the genetic algorithm also is attached to this paper.

Highlights

In the control systems of induction motors, the state variables of the motor need to be estimated based on methods such as vector control, direct torque control and multiscalar control
The model is simplified, it enables testing the observer’s performance between lines 67–223. Both files may be used for induction motors that are different from the one used presence noises and variations
The observer’s gains line 68 of the file START sim.sce, and new gains values should be typed in the appropriate places between lines 67–223. Both files may be used for induction motors that are different from the one used by the authors

Summary

Introduction

In the control systems of induction motors, the state variables of the motor need to be estimated based on methods such as vector control, direct torque control and multiscalar control. The values of state variables, such as magnetic fluxes coupled with the rotor windings, and sometimes angular speed, are applied in the control system as feedback signals. The estimation quality has a crucial impact on the accuracy of the overall control process. In the literature on modern control systems of induction machines, the authors pay attention to the fact that the accuracy of magnetic flux estimation (both the module and the flux vector argument) has a significant impact on the quality of control in these control systems. The works [4,5,6,7] provide a review of various modern control systems of induction machines used in practice: Field Oriented

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Discussion

Conclusion