| 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, which can not only raise the function and the level of the building, but also save the energy. At present, air-conditioning design in internal commercial building is becoming more complex and enormous. The proportion of air-conditioning system in the whole building is getting larger. In order to control and manage the air-conditioning system effectively, and take full use of energy-saving technology, we apply computer control to the system of air automation control. This paper discusses the direct digital control (DDC) in the air-handing unit of air-conditioning system.Variable air volume (VAV) air-conditioning system is superior to the other air-conditioning systems for its economic and flexible performance, which has been the main current of air-conditioning system design. But as a complex thermodynamic system, VAV system has many disturbances and is calculated parameters hardly. Many new intelligent control theories come into being with the development of computer and control theory. This paper introduces a compound Fuzzy-PID control algorithm which uses fuzzy control in big error and PID control in small error. After combining fuzzy control and PID control, the control algorithm has both advantages of them. So we can solve the contraction between stability and good performance of the system, and strengthen the system adaptability to some unstable factors.MATLAB is one of the popular software recently. This paper uses its SIMULINK toolbox to simulate the system. It introduces the process of establishing simulating model exhaustively, and analyses the simulating results. The results lay a foundation for later engineering use, which indicate that the compound Fuzzy-PID control has the better function than the common PID control.
|
PDF Full Text Request