C/E-PLC Automata-Formal Verification Of Hybrid Systems And Its Application On Chemical Process Control

Hybrid System is a kind of complicated dynamic variation system, which exists not only in continuous dynamic variables but also in discrete logic variables. At present , the research on it arises at the very outset. The miscellany performance is very common in the flow manufacture process, the modeling method to this process is far from mature at present.. Meanwhile, Programming Logic Control (PLC) is widely used in industrial practice .As is well_known, on account of many reasons , in fact ,the formal verification of critical parametes in PLC program are impossible to be tested repeatedly during our practice. To solve the controlling problems,we have to simulate the real conditions in laboratary. By this means, we can judge wheather the parametes meet our practical needs.In the first place, combining the research work of many predecessors in the relevant field, this paper analyses several modeling methods, mathematic theories and behavior characters of the Hybrid System .What's more, its concretely form of principles of verification is provided. Subsequently this paper discusses the theory and property of PLC automata and its corresponding example.In the following content , condition/event(C/E)model and its connection mode are addressed. Based on above paragraphs, we draw a conclusion that PLC automata and C/E have their own deficiency severally, when they are applied in industrial hybrid control system。As a result of solving the existing problem, the paper proposes a new controlling model, called technology of C/E-PLC automata, as the principles of verification of hybrid control system modeling and PLC program controlling. According to setting up the C/E-PLC controlling model to the material evaporation process of chemical intermitting reaction, it analyzes the hybrid performance and the operation performance of the system. This technology combines the merits of PLC automata and C/E model ,so it can get over their originally shortage. In this new technology of controlling model, rectangular state space technique servers to sub-systems. In the end, in order to illustrate further my point of view, the process of chemical intermitting reaction of chemical plant is described in this paper in detail. There we use the technology of C/E-PLC automata. Helped with Simulink and Stateflow included in Matlab, we get the satisfied result of simulation.As is shown in the paper , due to making use of C/E-PLC automata to model and to set up principles of verification, an exciting new field of Hybrid Control System has opened up. With the widely use in industry and research of PLC ,we can see the universality of this technology applied in chemical plant。These facts convince us that the technology of C/E-PLC controlling model automata has a brilliant future.