The Research On Embedded Controller Of VRV Central Air Conditioning System Based On Self-Tuning Fuzzy-Pid Control

In CHINA, building energy consumption has a proportion of about 20% in total energy consumption, while the air-conditioning energy consumption accounted for around 85% of building energy consumption; VRV central air-conditioning has been wildly used because of its good characteristics. VRV central air conditioning system is a cold cryogen air conditioning system, which is made up of outdoor heat echanger, compressor and other subordinate parts by transmitting cryogen. Because VRV air conditioning system is a multi-interference, large inertia, the height of strong time-varying nonlinear systems, it's difficult to set up the actual control model. Therefore, it is difficult to achieve good control effect by model-based control of the traditional control algorithms, such as PID control. The loop control strategy of VRV central air-conditioning has key influence in order to make it run best. It's able to meet the requirements of process conditions under the premise of minimizing energy consumption, so it's of great practical significance.In this paper, Fuzzy-PID control strategy has been used in characteristic research of VRV central air-conditioning system by ARM9-Linux embedded development platform in order to optimize control problem of the variable load, VAV and improve the effectiveness of the controller. The following work has been made:(1)Fuzzy control methods to adjust the parameters of PID control, that is, adjust PID parameters of fuzzy control algorithms, make good result. A detailed fuzzy PID controller design method is introduced through this paper.(2)According to the needs of VRV system, U-Boot-1.2.0 has been used as an embedded controller Bootloader; In order to meet real-time requires for the VRV air conditioning embedded controller Linux-2.6 kernel has been used in it, at the same time a mixed root file system of CRAMFS and yaffs has been set up.This paper uses HVAC refrigerating system to simulate the VRV central air conditioning system. The use of fuzzy PID control method of VRV air-conditioning systems control make the room temperature steady and response speed are better than traditional PID control between fuzzy PID control method and traditional PID control by control curve.