Practice ArticleHybrid intelligent control of substrate feeding for industrial fed-batch chlortetracycline fermentation process

- A hybrid intelligent control method for substrate feeding is proposed.
- A novel TIVSS soft sensing algorithm is proposed for substrate prediction.
- The tracking performance, regulation stability and final yields are analyzed.
- The proposed method enables the automatic control of substrate feeding.
- Successful applications to industrial fed-batch chlortetracycline cultivation process.

The lack of accurate process models and reliable online sensors for substrate measurements poses significant challenges for controlling substrate feeding accurately, automatically and optimally in fed-batch fermentation industries. It is still a common practice to regulate the feeding rate based upon manual operations. To address this issue, a hybrid intelligent control method is proposed to enable automatic substrate feeding. The resulting control system consists of three modules: a presetting module for providing initial set-points; a predictive module for estimating substrate concentration online based on a new time interval-varying soft sensing algorithm; and a feedback compensator using expert rules. The effectiveness of the proposed approach is demonstrated through its successful applications to the industrial fed-batch chlortetracycline fermentation process.