The Central Air Conditioning System Based On Distributed Control System

The air conditioner system of the high accuracy is that necessary technology in thedeveloping society nowadays. The control of the traditional air conditioner system isbackward in technique, not merely waste a large amount of energy, and can’t meet demand,the high accuracy of control at all. Based on the background of designing the power plantcontrol room air conditioning system. Introduces the application of computer distributedcontrol system (DCS)in central air conditioning automatic control system.In this paper, based on the analysis of the backward situation in central air conditioningcontrol system, Starting from the control system theory, put computer, communication,display and control together effectively, with its characteristics：decentralized control,centralized operation, classification management, flexible configuration, can effectively solvethe current backward situation.First of all, in this paper, starting from the process and principle of central airconditioning, expounds the control of air conditioning parts and the present situation of the airconditioning control system，and control system as the breakthrough point，In general, areasonable design scheme—distributed control systems proposed. Then, on the basis of theentire hardware part of the selection is discussed in detail. After then,this system adopts PIDcontrol theory, in order to make the temperature and humidity control to achieve controlrequirements. Finally this control system adopts Siemens S7-300PLC, application of MPIcommunication is established based on the WinCC PC system constitute a complete controlsystem.Through the system debugging can indicate，using computer collecting and distributingcontrol system (DCS) can satisfy the control requirement. The system through the practice toprove its reliable operation, to the stability of the control of indoor temperature and humidity,achieve the technological and design requirements.