ABSTRACT
Time delay control (TDC) is used for the bioprocess. To generate reference trajectories for the bioprocess variables, genetic algorithm has been used. The working of TDC was checked by simulation experiments in different operating modes. This was followed by experimentation on a fabricated prototype bioreactor. There is also room for improvement in the design aspect of the fabricated bioreactor. TDC and the developed observer were examined by simulation for all the operating modes. The results were satisfactory. For the bioprocess controller, first a generalized model with double-substrate limitation was framed. The bioprocess model considered is basically an unsegregated and unstructured model having four bioprocess state variables and four control inputs. The environmental control, that is, the control of the temperature, and pH of the reactor medium to their predefined values were done using on-off and proportional controllers, respectively. Environmental controls remained operative for the whole fermentation period.
