A Novel of Two-Degree-of-Freedom Smith Predictor Based on Fractional Order PID Controller in Paper Basis Weight Control

The work aims to solve the paper basis weight distribution uniformity via long time delay process control strategy. According to the characteristics of large time-delay, time-varying nonlinear in paper basic weight control, a novel Smith predictor is proposed in this paper. Fractional order PID controller is applied in the design of a two-degree-of-freedom Smith predictor. It has the capability to control the set value track and load disturbance independently. Set point tracking adopt traditional Smith controller. Fractional order PID controller with strong anti-interference and robustness is served for load disturbance. Simulation results show that the two-degree-of-freedom Smith predictor can effectively restrain the damage of the delay time on the stability of the system, and improves the robustness effectively when the model mismatched. In practical application, paper basic weight deviation can be controlled effectively.