Characteristics and Performance of an Autotuning Proportional Integral Derivative Controller for Dissolved Oxygen Concentration

Abstract

The characteristics and performance of an autotuning proportional integral derivative (PID) controller developed by us have been investigated. T h e parameters for this controller, proportional gain, K , the integral time constant, Ti, and the derivative time constant, Td, are on-line-tuned by using heuristic rules, requiring no a priori tuning. The controller showed a stable and robust performance, even when only K was online-tuned. However, the dynamic (or time delay) of the membrane-type dissolved oxygen (DO) probe caused oscillations in the DO concentration unless it was properly compensated. This required a prediction method. When all three controller parameters were on-line-adjusted, the DO probe dynamic could be effectively overcome with no separate prediction step.

Adaptive pole placement control algorithm for DO-control in β-lactamase production

“…Most fermentation systems are complex, time-varying, and highly nonlinear in nature, especially in a batch culture system, where the dynamic behavior changes during the fermentation as a result of antifoam addition, biomass accumulation, microbial respiration, and product formation (Lee et al, 1994). Therefore, the control of the DO is difficult because the mass transfer characteristics of the system are not constant and depend on the temperature, media composition, agitation rate, cell growth (Vardar-Sukan, 1985), headspace pressure, and aeration rate.…”

“…Hwang et al (1991) used an algorithm which adapted the settings of the PID controller with a heuristic rule based on the supervision of certain performance indices. Lee et al (1994) have developed an autotuning PID DO controller with agitation rate as the manipulated variable. Three indices, the output variance, the mean value of the control error, and the input variance were calculated on-line with a moving window.…”

Enhancement of glucose oxidase production in batch cultivation of recombinant Saccharomyces cerevisiae: optimization of oxygen transfer condition

“…Batch fermentation systems are complex, time-varying and non-linear in nature where dynamic behaviour changes during the fermentation as a result of biomass accumulation, microbial respiration and product formation (Lee et al 1994). Therefore, the control of DO is dif®cult since the mass transfer characteristics of the system is not constant and depends on the temperature, media composition, agitation rate and cell growth (Vardar-Sukan 1985).…”

A plug-and-play system for enzyme production at commercially viable levels in fed-batch cultures of Escherichia coli BL21 (DE3)

“…The DO-stat method is therefore more responsive to the real time metabolic situation of the cell (Farell et al 2015), and doesn’t involve iterative process development as in the case of exponential feeding. In defined media, DO-stat also responds faster to nutrient depletion than other indirect feedback control strategies such as pH-stat (Lee et al 1996, Picotto et al 2017). Based on these advantages, the DO-stat feeding approach was chosen for this study.…”