Research And Implementation For Fuzzy PID Temperature Control System Based On ARM

Thermal Analyzer temperature control system has characteristics of non-linearity, time-variance and time-lag. However, for such system, conventional PID controller can not meet a wide range of precision temperature control requirements. Fuzzy control is an intelligent control method. It has the characteristics of a simple structure while doesn't need a precise mathematical model. Fuzzy control has been applied such as televisions, video camera, washing machines, refrigerators, rice cookers, air conditioners, cameras, photocopiers and many other aspects. In order to improve a wide range of temperature control accuracy, by combining fuzzy and PID control methods a fuzzy PID temperature control system of the thermal analyzer based on ARM microprocessor is designed and implemented.In this paper, the hardware has been designed by using 32-bit ARM7 processor LPC2368 as the core. The system selected the temperature sensor of Platinum-Rhodium thermocouple. The zero-crossing detection opt coupler devices and TRIAC make up the implementation unit. Human-computer interaction interface composes of the key and LCD. The system software includes PC and LPC2368 programs. PC program is developed using C++ language under C++ Builder 6.0 development environment. It achieves receiving data and sending command from LPC2368 by RS232, and then displays real-time results in the main form, and other functions; LPC2368 controller program is developed using C language under ADS1.2 integrated development environment. It achieves task as: system initialization, receiving command, filter processing, realization of control algorithm, outputting the controlled results, sending data and so on.The fuzzy PID controller design algorithm is studied in this paper. The hardware platform of the thermal analyzer temperature control system is designed. The simulation analysis is carried out with MATLAB tools for the conventional PID and fuzzy PID control method. The experiment is carried out in the actual designed system platform. The experimental results show that fuzzy PID has a better dynamic response and steady state characteristics, and has stronger anti-interference ability and good robustness. These results also show that the temperature control system of the thermal analyzer can satisfy the requirements of a wide range of temperature control accuracy.