On-line application of an auto-tuning PI D controller for dissolved oxygen concentration in a fermentation process

Biotechnological processes are notoriously difficult to control because of their non-linear time-variant characteristics. The application of an autotuning PID controller is presented as a viable aid as either a means to determine suitable tuning PID parameter values or as a retuning controller, initiated either automatically or by an operator. The controller operation is introduced and on-line results presented to compare the performance of the autotuner with a well-tuned PID controller on both batch and fed-batch fermentations. The benefits for the operator and process operation are demonstrated with on-line results on batch anti fed-batch fermentation processes.