Multiobjective robust PID controller design for various industrial processes

Abstract

In this paper, Non-dominated Sorting Particle Swarm Optimization (NSPSO) is applied to design multiobjective ro- bust Proportional-Integral-Derivative (PID) controllers for various industrial processes such as distillation column plant, liquid level control system and DC servo motor control system. Multiobjective robust PID controller design problem is formulated by minimizing Integral Squared Error (ISE) and balanced robust performance criteria. The performance of various optimal PID controllers is compared in terms of ISE and robust criteria. For the purpose of comparison, NSPSO and Non-dominated Sorting Genetic Algorithm-II (NSGA-II) methods are considered. The performance of PID controllers obtained using NSPSO is better than that of NSGA-II. The results reveal that NSPSO yields better robustness and consistency in terms of integral squared error (ISE) and balanced robust performance criteria than NSGA-II for various industrial processes.