Direct synthesis based tuning of the parallel control structure for integrating processes

Abstract

A controller tuned for servo/regulatory application gives significant performance degradation when used for regulatory/servo purpose. The degradation in the overall performance can be minimised by a two degree-of-freedom control structure. The parallel control structure reported recently decouples set-point tracking from disturbance rejection. In the present work, the two controllers of parallel control structure are designed using direct synthesis approach to achieve robust closed-loop performance for a class of integrating processes. Simulation examples show that improved servo and regulatory performances are achieved by the proposed method as compared to the recently reported strategies when the controllers are tuned to have the same degree of robustness.

Keywords:

• direct synthesis method
• integrating process
• maximum sensitivity
• robustness
• total variation

Additional information

Notes on contributors

Moina Ajmeri

Moina Ajmeri received her bachelor's and master's degree in Electronics and Communication Engineering from Magadh University, India, and BIT Mesra, India, respectively. She is currently working for her PhD in the Department of Electrical Engineering, Indian Institute of Technology Patna, Patna, India, in the area of controller design. Her research interests include control of integrating and unstable processes with time delay.

Ahmad Ali

Ahmad Ali is currently working as an assistant professor in the Department of Electrical Engineering, Indian Institute of Technology Patna, Patna, India. His research interests include control systems, evolutionary algorithms, new tuning strategies for controller design and relay-based system identification.