Study of a Dynamic Predictive PID Control Algorithm

The large delay system is common in the process of industrial production at the same time it is difficult to control. Most systems have characteristics that their transfer functions vary with load. By using traditional PID control algorithm, the control effect has large overshoot, long adjusting time, it is hard to get an ideal control effect and hard to ensure the control quality. Therefore, in order to solve the control problem of large delay system a dynamic predictive PID control algorithm is proposed in this paper. The control strategy of this method is to apply a prediction model to traditional PID control system. In this way, the characteristics of large delay control object are reflected to controller in advance, then according to prediction error the controller sends out control signal, controller´s control function is just acting on the controlled object after system inherent delay time. This proposed algorithm is applied to control superheated steam temperature on the full-scope simulator of 600MW power generating unit. Experimental results show that dynamic predictive PID control algorithm can solve the control problem of large delay system, and can effectively improve the control quality.