Novel feeding strategy for adaptive control of bioreactor processes

In this paper a novel feeding strategy is suggested for bioreactor processes. The strategy, referred to as the modified linear feeding strategy (MLFS), is shown to overcome the disadvantages of the feedback exponential feeding strategy and the linear feeding strategy, resulting in a fast response in substrate concentration for a large range of values of initial conditions. It is also shown that one of the main features of the MLFS is that it effectively decomposes the closed-loop system into a fast and a slow subsystem. This property is used to prove that the control input cannot saturate in the case when an adaptive version of MLFS is used to control the processes with Haldane kinetics. In the latter case, the MLFS is also shown to effectively help in assuring the stability of the closed-loop system. Applications of the MLFS in both nonadaptive and adaptive cases are illustrated through computer simulations.