Optimization of Pid Controller for a Nonlinear Mimo System and Comparative Performance Analysis

PID controllers are designed and optimized in this paper for wood-berry distillation column using simulated annealing algorithm and particle swarm optimization method. PID controllers are the common instruments used in control applications. Construction of PID controllers is smooth and easy. It furnishes more stability and malleable while governing the processes. Thousands of PID loops strive to keep processes safe, stable, and profitable. Tuning of PID controller is the process of finding the values of constants named proportional constant KP, integral constant Ki and derivative constant Kd. It is easy to tune PID controller gains of a continuous system. But there are many nonlinear plants in industry. Higher order, time delays, harmonics, poor damping, instability, time-varying dynamics, set points are not followed, valves swing around and creating oscillations etc are the problems related to the nonlinear system. Thus the design of controller for a nonlinear process is a risky work. This paper illustrates a comparison between the optimal tuning algorithms such as particle swarm optimization method and simulated annealing algorithm used to tune PID controller for a nonlinear system. The comparison between the superior performance of SA tuned PID and PSO tuned PID controller are given.