Unified Structure of Adaptive System for Control of Basic Process Variables in Biotechnological Cultivation Processes: Ph Control System Case Study

Abstract

A unified scheme for control of the important bioprocess variables is proposed in this case study. The scheme includes feedback PI controller, controller adaptation algorithm based on statistical characteristic of the controlled variable, and feedforward compensator. In this case study, an adaptive pH control system is investigated. The adaptation algorithm analyses statistical characteristic of the controlled variable in on-line mode and performs adaptation of the controller’s parameter when dynamics of the control channel has changed. The feedforward compensator employs oxygen uptake rate estimates to compensate system’s load disturbances related to the time-varying biomass growth rate and biomass concentration in the bioreactor. Simulation runs of the pH control system have demonstrated that the proposed unified control scheme can increase performance of the control system.