Development of an optimized fractional-order controller featuring dead-time and disturbance compensation
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Prashant Garg
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Brijendra Mishra
Abstract
This work highlights a unique control scheme tailored for time-delayed systems under disturbances, blending a fractional filter, dead-time adjustment, and a disturbance compensator. The controller is designed using the Internal Model Control (IMC) approach and optimized through the Snake Optimization (SO) algorithm. This control scheme is applied to practical problems, such as heat exchanger systems and First Order Integrating Plus Delay Time (FOIPDT) process. Integral Absolute Error (IAE) and Integral Square Error (ISE) are key metrics for analyzing closed-loop control performance relative to existing methods. The scheme effectively enhances the closed-loop response by improving IAE values and minimizing control efforts needed to accomplish the preferred output. The Riemann surface principle is utilized for stability analysis. Disturbance rejection and robustness tests show significant improvements in closed-loop response, as illustrated in the numerical simulations.
Acknowledgments
The authors gratefully acknowledges the guidance of Dr. Manish Yadav for his insightful feedback.
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Research ethics: Not applicable.
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Informed consent: Not applicable.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest The authors states no conflict of interest.
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Research funding: None declared.
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Data availability: Not applicable.
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