Fuzzy auto-tuning PID control of a small electric-heating reactor

Small electric-heating reactors are widely used in chemical experiments, fine and special chemical production processes. Because of their large time-delay, strong nonlinearity and time-varying properties, they are difficult to control accurately using the ordinary PID controller with fixed PID parameters. By summarizing the PID tuning experience and knowledge of human operators into fuzzy tuning rules, a fuzzy auto-tuning PID (FA-PID) control algorithm was developed for the temperature control of a small electric-heating reactor using the fuzzy tuning rules to tune PID parameters real-time on-line. The FA-PID control algorithm was successfully implemented in Matlab software using its M programming language, and integrated tightly with configuration and monitoring software KINGVIEW through their dynamic data exchange (DDE) channel. The FA-PID control system was applied to the temperature control experiments of a small electric-heating reactor with strong nonlinear and time-varying properties, and it achieved much better control performance than the ordinary PID controller. The experimental results demonstrated that FA-PID had good adaptability to process changes.