Active Disturbance Refutation-Based Filtered Smith Predictor Design for Fractional-Order Semi-Markovian Switching Systems and Its Applications

This paper focuses on the issues of tracking controller enhancement, input delay rectification, and disturbance elimination for dynamical systems characterized as fractional-order semi-Markovian jump processes. In particular, the design of the modified repetitive control technique integrated with the filtered Smith predictor scheme based on the Majhi–Atherton approach guarantees exact tracking performance and disturbance elimination. To be more specific, the active rectification of both external disturbances and delays is safeguarded by the construction of a modified proportional derivative-based active disturbance estimator along with the traditional Smith predictor framework. Also, the modified repetitive control in this framework is able to track the reference signals with multiple periodicities. In accordance with the Lyapunov stability criterion, a group of applicable principles is produced in the structure of matrix inequality constraints. Furthermore, the parameters of the controller block are designed concurrently by way of elucidating the stated matrix inequality constraints. Finally, the simulation results and the comparison analysis between the developed control technique and existing works such as equivalent input disturbance and the truncated predictor feedback control method validate the advantage of the recommended control framework.