A HYBRID MODELING AND VERIFICATION PARADIGM FOR EMBEDDED CONTROL-SYSTEMS

Contemporary process control includes continuous and discrete componen ts. At the lowest level, continuous PID controllers are used for actua tion and control. At a higher level, supervisory control mechanisms ar e used to select appropriate control algorithms for the different mode s of system operation to achieve optimal or near-optimal control. Mode ling and analysis of such combined discrete and continuous components requires hybrid modeling techniques. This paper presents a hybrid mode ling paradigm, and discusses its execution semantics, which are based on the principles of invariance of state and temporal evolution of sla te. The modeling and simulation methodology is used to analyze the con trol behavior of dynamic physical systems, and a model-verification te chnique based on divergence of time demonstrates possible applications in design tasks. (C) 1998 Elsevier Science Ltd. All rights reserved.