Abstract
For the control system with the hysteretic characteristics on temperature, the combination of PID and fuzzy control were put forward and a fuzzy self-adjusting PID controller for heater system was built, in which fuzzy control rules are used for PID parameters self-tuning. By simulation and compared with other ordinary PID controls, it’s concluded that the method used in a hydraulic servo system can greatly improve the robustness and the dynamic static and properties of the system, which can achieve the desired effect of zero overshoot, short response time and high steady precision.