OPC-UA information model for large-scale process control applications

The distributed and networked control of large-scale systems is typically designed as multi-layer control architecture. This brings advantage of a simplified design for complex control strategies; however, it complicates the information consistency between individual layers (PID controllers, advanced process controllers, real time optimizers) under changes in controlled plant topology and other events. Individual control layers require different representation of knowledge; however, the information solution has to guarantee the cross-layer integration, consistency and uniform representation of on-line and off-line process data, topology information and dynamics/performance models. The paper presents solution based on OPC Unified Architecture (OPC-UA) model and two levels control architecture. The solution unifies representation of data and topology in Service Oriented Architecture (SOA) and adopts Cloud Computing paradigm.