Optimal variable structure control with sliding modes for unstable processes

Abstract

In this work, a variable structure control (VSC) technique is proposed to achieve satisfactory robustness for unstable processes. Optimal values of unknown parameters of VSC are obtained using Whale optimization algorithm which was recently reported in literature. Stability analysis has been done to verify the suitability of the proposed structure for industrial processes. The proposed control strategy is applied to three different types of unstable processes including non-minimum phase and nonlinear systems. A comparative study ensures that the proposed scheme gives superior performance over the recently reported VSC system. Furthermore, the proposed method gives satisfactory results for a cart inverted pendulum system in the presence of external disturbance and noise.

Keywords

variable structure control / sliding mode control / Whale optimization algorithm / robustness / non-linear system

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