The Research Of The High-Precision Control Theory And The System Design Of Constant Temperature Box

The high precision temperature control is very important in the modern precision measurement system; therefore, the research of high precision temperature control makes lots of sense. But the normal control tactics can not suffice the demand, so the new tactics must be studied on the exiting ones.The PID control arithmetic is the main research object in this thesis. To get over the PID's shortcoming, the study of the fuzzy self-adapting control arithmetic is done. By the Matlab simulation, the main disadvantage of the PID arithmetic is found, which is the parameter of PID controller can not adapt the variety of object. So the control precision is limited when the object is time-variational. The fuzzy control theory is applied in many fields because of its robustness and insensitivity. Therefore the two arithmetic are combined to be a fuzzy self-adapting control arithmetic, which is proved by the emulator that can improve the normal PID's adaptability and precision.The mechanical structure of the box is designed and the program of the temperature measurement and control is compiled according to the demand of the project. By the mechanical design, the air in the box turn to be a piston distribution, which makes the temperature's equality is improved. The program is combined the strongpoint of Matlab and Labview, which uses the Matlab script in the Labview to improve the ability of data operation in the program. So the advanced control arithmetic can be applied in the Labview G program.The different tactics are applied in the constant temperature box control system. The experiment data shows that the stability is less than 0.05 ℃, which proves the rationality and the validity of the fuzzy self-adapting control arithmetic and the constant temperature control system design.