A fuzzy logic controller to control nutrient dosage in a fed-batch baker's yeast process
A fuzzy logic controller designed to control glucose feeding in a fed-batch baker's yeast process is presented. Feeding is carried out in portions and the controller determines the time at which glucose should be added and computes the size of the portion to provide the maximum glucose uptake rate. Moreover, the controller detects and prevents the occurrence of overdosage. The experimental results indicate that yield and specific growth rate obtained with the controller approached 55% and 0.13 h−1, respectively.
Design and simulation of a fuzzy controller for fed-batch yeast fermentation
In baker's yeast fermentation, the process is non-linear and the response of the system to changes in glucose feeding has a very long delay time. Therefore, a conventional system can not give satisfactory results. In this paper, a fuzzy controller designed to control a fed-batch fermenter is presented. The fuzzy controller uses Respiratory Quotient (RQ) as a controller input and produces glucose feeding rate as control variable. The controller has been tested on a simulated fed-batch fermenter. The results show that the maximum yeast production is possible by keeping the specific growth rate (μ) and the glucose concentration (Cs) at preset values (μCand Cs,c) and minimizing the ethanol production.
Fuzzy Control Application to Glutamic Acid Fermentation
Abstract Consumption rate of ammonia in glutamic acid fermentation was found to be correlated with consumption rate of sugar. This gives a good control strategy for sugar feed rate to keep sugar concentration in a suitable range in fed-batch culture of glutamic acid fermentation. Slight changes of culture conditions, however, make some troubles in this control scheme. Fuzzy theory application could be found to be effective in such cases.