Tension control in unwinding system based on nonlinear dynamic matrix control algorithm

The paper presents a novel method to control tension in unwinding web systems. In unwinding web systems, the processing flow of the unwinding and winding rolls is continuously carried out. With the diameter of roll changing, the tension of the film changes as well. If the tension is too small, the film relaxation will produce lateral drift, to the contrary, the tension will cause the film to wrinkle or even break if it is too large. Therefore, keeping tension stable is an important prerequisite to ensure alignment accuracy. Hence, a Nonlinear Dynamic Matrix Control (NDMC) algorithm is proposed to control tension based on a math model of dynamic unwinding tension. The algorithm has a better performance than the PID algorithm, the validity of the means is tested through computer simulation and discussion.