Self-tuning PI control of a pH neutralisation process

The paper shows how a certain self-tuning algorithm can be interpreted as a self-tuning PI controller, and this algorithm has been successfully tested on a full-scale pH neutralisation process. Extended trials showed that although this process could be well controlled by a fixed parameter PI controller, the self-tuning algorithm could easily find suitable fixed parameter values for the controller, whereas human operators found the tuning difficult, if not impossible.