Research On Embedded Temperature Control System Based On The Fuzzy PID

There is important meaning on the economic benefits improving of the agriculture production to control the environment of the greenhouse, create suitable growing condition for plants and make the crops obtain high yield. Temperature is an important environmental parameter in the greenhouse. How to make use of the automatic control system to control the temperature of the greenhouse effectively and improve the temperature control precision of the greenhouse is one of the important subject in greenhouse research of our country at present. It has great meaning in heightening the level of greenhouse industry of our country.In this dissertation a new type of embedded temperature control system of the greenhouse is designed. High precision, fast sampling and response speed, low power consumption are the goals. At first an overview about the developing history, current research status and development trend of the greenhouse is discussed. And then the character of ARM technique is summarized briefly. Then the overall scheme of the temperature control system is planned. The whole system is divided into 5 modules, including CPU core module, analog circuit module, system memory module, system input and output module, PC communication module. And then a detailed dissertation about the software and hardware design based on S3C44B0X is given. The function of S3C44B0X is introduced briefly in the hardware part first. Then a specific introduction about the analog circuit design, the memory interface circuit design, the communication interface circuit design, the input and output interface circuit design is given. The uCLinux operation system which is the software developing platform is introduced first. Then the structure of the operation system core, the modifying, the configuring and transplanting of the operation system core are analyzed. And then the relevant design of the application program and the device driver program is done. The deploying and managing of the real-time multi-task are also realized. And then the control algorithm applicable to the system is discussed according to the character and design requirements of the system. On the basis of the analyzing on the control system the fuzzy self-adjust strategy is put forth through establishing the mathematical model of the system, joining the fuzzy control theory and MATLAB software. Fuzzy deducing and traditional PID control are combined to make the system be more adaptable to the changing of the temperature. The simulation result shows that fuzzy self-adjust PID control strategy has not only the advantage of the PID control strategy but also the self-adaptive and self-study functions. It has also good dynamic and steady state performance.At last a summary of the whole dissertation is given, the shortage of this dissertation is pointed out and the problems need solving lately are put forth.