Self-tuning PID Controller with Variable Parameters Based on Particle Swarm Optimization

In order to deal with the time-varying, nonlinear, and large-lagging problems in the auto-chlorination control process of tap water, a self-tuning PID chlorination controller with variable parameters based on PSO is proposed in this paper. By finding the relationship between k_p, k_i, k_d and the deviation, the s-functions are written to complete the design of self-tuning PID controller with variable parameters. Then, particle swarm optimization is used for achieving the correction coefficient values of deviation which are sent to the controller so that the control effect of chlorination system is improved. At the same time, compared with the fuzzy PID controller, the difficulty of controller rules extraction is solved. The simulation results of auto-chlorination control system show that the controller is stable and reliable. Hence, an effective control for auto-chlorination control system can be realized.