A stage-based quality prediction and control method for batch processes

A quality prediction method is proposed for multistage batch process. Firstly, using clustering methods based on the stage-based sub-PCA, the process is divided into several operation stages according to the change of process correlation, the most relevant stage to the quality variable is defined, and then sub-MPLS models are developed for that stage for online quality prediction. In addition, a closed-loop quality control system is proposed. The proposed method is finally applied to the injection molding process, a typical multistage batch process, and the results prove the effectiveness of the proposed quality prediction method and quality control scheme.