Development Of A New Type PID Thermostat

Measure and control of temperature is a daily problem in daily life and manufacture. The level of thermostat directly affects the productivity, the production quality even the safety of equipments and human's life in the domain of manufacture, aviation and spaceflight. Infrared sensor is the crucial device of infrared thermometer. There are many kinds of infrared sensors and the thermoelectrical infrared sensor is widely used. This kind of sensor is sensitive, swift and credible. It can be refrigerated rapidly and is very easy to use. Because of the sensor is easy to be influenced by temperature and few kinds of thermostat is aim at it. It is necessary to develop a kind of special thermostat with high accuracy.PID Control is the earliest control means. It has the simple construction, good robustness, and high credibility, and used wildly in industry control systems, especially where precision mathematics model can be established. Thanks to the development of microprocessors, intelligentized thermostats are getting smaller and powerful and they have been used more and more widely. Combine PID control with fuzzy control, the thermostat has both the accuracy of PID control and the facility of fuzzy control, and it can make perfect effect on the nonlinear or time varying systems.By develop the new type thermostat module which is specialized in the thermoelectrical HgCdTe infrared sensor, I have studied some advanced temperature control technique and mapped out a scheme of fuzzy PID control. The core of the thermostat is PIC16F873A MCU, with abundant on-chip peripheral equipment and the software. It has carried out some advanced function at least hardware cost such as the control parameter self-tuning, Sensor identification and failure diagnosis, and is very easy to use. The designing of the software used for reference of the working of operating systems, a system management program manages all the subprograms, each subprogram is extremely modularized and independence of each other. This structure improved the readability and maintainability of the program.This design has carry out the function of PID control parameters self-tuning...