Thesis:

Design of sliding mode controller to prevent chaos in permanent magnet motor in the presence of disturbance

Synchronous machines are known as the beating heart of the industry and electric power, and one of the common instabilities in these machines is the existence of chaos. This characteristic causes the formation of limit cycles and the introduction of the emergence of basic instabilities for this vital tool, and for this reason, a wide range of studies are being conducted to mitigate and control this instability. With the aim of managing and mitigating this unpleasant phenomenon in synchronous machines, this study presents a new nonlinear control strategy based on the robust sliding mode approach. In controller design and stability proof, parameter uncertainty and system disturbances are considered. Also, an adaptive approach has been used to obtain optimal coefficients for the sliding mode method. Bounded perturbations with an unknown upper bound are also applied to the system and the stability of the system is guaranteed using the Lyapunov method. In the structure of the proposed robust controller, the concept of virtual signals is used and the implementation of this method on a sample synchronous machine in the MATLAB environment guarantees the capability and ability of the proposed method to prevent the occurrence of chaos under the most severe working conditions.

Keywords: chaos phenomenon, synchronous machine, parameter uncertainty, nonlinear control, disturbances.