ABSTRACT
A desired performance of any process depends on the control action taken by the controller. Control system engineering is mainly concerned with understanding and controlling the process governed by any system to accomplish an objective and to provide useful economic products for society. Many practitioners and researchers in the field of control agree that controller design can be quite laborious in cases where the plant is unstable. The controller synthesis becomes a challenge for such systems because there are certain design and closed-loop performance limitations that narrow the range of feasible solutions. These constraints reflect in overshoots, peaks in sensitivity functions, and closed-loop band width. Choice of control structure and the design approach depend considerably on a priori knowledge of the process dynamics and system requirements. This paper mainly focuses on design and tuning of Proportional Integral Derivative (PID) controller for an unstable system. A comparative analysis of different conventional and real-time tuning methods is also presented based on detailed simulation studies. The study shows the effectiveness of suitable tuning method to control the unstable system for obtaining the desired performance out of it.
