Research of PID Parameter Self-Tuning Applied in Temperature Control System

A new PID parameter self-tuning algorithm is proposed, which adapts to single plant. Guaranteeing the stabilization of closed loop systems and satisfying the conditions of self-tuning, we can use recursion least squares method and estimate the change of model parameter of the plant online. The PID self-tuning control algorithm is applied to control and research the real-time temperature of the resistance furnace. The conditions of the PID self-tuning: When the difference of the real-time temperature and the hypothesis temperature lesplusmn 1degC, stop the identification, turn to the conventional PID control. If the difference gesplusmndegC, then online identify each PID parameter. Looked from the control result, this algorithm has the good adjustment and the track performance, constant temperature error lesplusmn0.5degC, Track temperature lesplusmn2degC, also the algorithm is simple and easy to transplant.