The Study Of Distributed Control System For Central Air-Conditioning

The subject of entry chiefly studies the temperature and humidity control of air-conditioning system based on the new air automation system of the optical institute of the astronavigation science and technology committee, and it also designs the computer supervision system on the base of RS-485 bus platform.The paper introduces the new air automation system of the optical institute of the astronavigation science and technology committee, and achieves temperature and humidity control and supervision software of the new air system .Then, the mathematical models of two modes (CAV and VAV system) are set up, and the transfer functions of the room are acquired, so the mathematical model also optimizes the system characteristic parameters. According to the transfer function of the room, the model of whole control system is created and the dynamic response curve is obtained by way of simulink software. Moreover, the paper introduces routine PID control of process control system, in order to resolve the inconvenience of selecting and adjusting PID parameters, so the fuzzy controller is designed .Through theory analysis and simulation experiments, we can come to a conclusion that fuzzy control is an ideal method, it has good feature of real time, little overshoot and quick response velocity and practical value. At the end of the paper, the computer supervision software is introduced.