P34: Streamlining PID Tuning of Dissolved Oxygen Control Loops on the Micro-24 System

The Micro-24 system, a 5 – 7 mL bioreactor which runs 24 independent and controlled experiments for screening and scale down studies, is unique in its flexibility to control process conditions from stem cells to industrial fermentations utilizing PID process control. Process control is a critical player in both industrial and biotech fermentation development, allowing more efficient scale down models and better process consistency.  However, the power of this tool is limited if it is not correctly implemented.  Accurate tuning of PID loops ensures that process setpoints are maintained with minimal noise, but tuning can be complicated by the difficulty of matching conditions to experimental demands.  To address these concerns, a novel abiotic method for tuning dissolved oxygen control loops was developed for the Micro-24 System.  New v4 software developments allowed variations in OUR associated with the process of interest to be accurately mimicked. This method provided accurate tuning against simulated growth conditions, eliminating the need for subsequent re-seeding during serial tuning exercises.  Without the need for user intervention, the process was easily automated, allowing streamlined optimization of PID parameters.