Just-in-time statistical process control for flexible fault management

A new fault detection and identification method is proposed to solve the problems that obstruct industrial applications of multivariate statistical process control (MSPC) techniques. The proposed method, referred to as just-in-time statistical process control (JIT-SPC), can realize flexible, adaptive, high-performance process monitoring. In addition, fault identification can be done through contribution plot in the framework of JIT-SPC. The usefulness of JIT-SPC is demonstrated through a numerical example, which conventional methods cannot cope with, and a case study of the vinyl acetate monomer production plant.