The Application Of Building Air-conditioning Control System

With the rapid development of Intelligent Building (IB), Building Automation System (BAS) has come to control and manage the equipment in the building more and more scientifically, economically and rationally. With the development of automation control , computer and communication , the air-conditioning automation control become more mature. Today , energy sources is more and more scarcity all of the world , air-conditioning system which has use a great deal of energy , how to save energy become more important and significance. As a important part of building automation, air-conditioning automation system improve using rate , optimize working state and time, prolong life and save energy . This paper discusses the pure-room control system of air-conditioning system.But as a complex thermodynamic system , air-conditioning has many disturbances, except weather ,structure, human, equipment which may effect it .The lag of temperature and humidity which take great difficult of control response speed. Temperature is associated with humidity ,temperature raised , humidity dropped;temperature dropped, humidity raised . The controlled parameter associate , effect each other . The pure-room control system require more controlled parameter, high control precision, quick response and energy-saving. It is great meaning to control all kind of parameter of pure-room system with right control flow.The content of the study is the pure-room air-conditioning control system, based on the Siemens apogee system . With the sensor , executor , control, I designed the pure-room air-conditioning automation system and control program , and install the equipment of wuhan national lab of optoelectronic.According to the trait of lab environment parameter, we let humidity sign have more priority when temperature sign and humidity sign come into conflict, let reheat improve temperature. We use the second-return wind instead of reheat .We use difference pressure of filter to control fan speed in order to keep lustration. We use low-price electricity of mid-night to restore heat, use restore heat at daytime which can save cost. We have get good control effect according repeat debug and adjust PID parameter. It provide base of experience for later project.Software system provide the alarm management which can monitor state of all kind of equipment;trend data collection can collect sensor data from controller and keep them as history newsreel which can see them at any time;dynamic plotter can see dynamic data change at real time;dynamic graph display real-time data change. Software system provide a convenient flat for system management.