Study On The Application Of Hybrid System Theory In The Temperature Control Of Supermarket Refrigeration System

With the continuous improvement of industrial automation and integration, systems with hybrid character is more and more popular. Hybrid system is widely used in manufacturing production, transportation, power system and ordinary life. Hybrid system is a complex dynamic system composed of the interaction of event-driven discrete-event subsystems and continuous-time evolving subsystems. Continuous and discrete dynamic characters are the basic attributes of hybrid system. Because of the hybrid dynamic character, hybrid system control has to control both the continuous evolving process and monitor the discrete behavior of the system and reflect the interaction of these two characters. The proposition and research of the hybrid system provide a good tool to describe both the coupling of characters of continuous and discrete dynamics and the complex dynamics phenomenon of the coupling and to understand some complex phenomenon in nature and society.because the research of continuous and discrete characters concerns two different mathematic models and the control of the two systems are based on their control theory respectively, Describe these two dynamic characters and their interaction become difficult, which impedes the development of the theory and application of hybrid control system. this paper research the application of refrigeratory temperature control in supermarket with hybrid system theory. Research includes:(1) summarizing the development of hybrid system in last ten years, including modeling theory, control method and research method. Pointing out the difficulties in the research and looking forward to the future research.(2) Deducing the mathematic model of supermarket refrigeratory system. Established hybrid automachine model, simulating with simulink and stateflow in matlab. Combined finite-state machine theory, state diagram and flow chart symbols. Described the event-driven system with chart and diagram.(3) Researched the characters of hybrid system, using air-conditioning system as a object, giving the simulation data and conclusion.(4) Established the MLD by deducing. Introduced hybrid modeling method based on MLD. Summarized three steps to establish the MLD model. (5) deduced supermarket refrigeratory hybrid system predicting controlmodel based on MLD. Did the simulation. The result shows that hybridsystem predicting control method solved supermarket refrigeratorysystem.the paper summarized the work and proposed the future research.