Modeling And Control Of The Speed-up Phase In Gravure Printing Machine Shaft-less Chromatography System

The shaft-less gravure printing machine is widely spread in modern printing industries. With the improvement of life quality, there is an increasing need for the printing machines with high speed and precision, and the acceleration process of gravure printing machine is a necessary process to achieve this demand results. Yet so far, research on acceleration process of the shaft-less gravure printing system is extremely scarce. Therefore, this thesis aims to build the dynamic model in the acceleration process of the shaft-less gravure printing system, and study the control algorithm based on the model.This thesis sets up the mathematical model between web tension and register error during the acceleration process based on the principle of mass conservation and torque balance; and the undetermined parameters used in the model are identified by the open-loop experimental data curves; and finally, the correctness and applicability of the mathematical model is validated with contrast of the simulation and experimental results.This thesis proposes a feedforward compensation fuzzy PD control algorithm based on the model, which is successfully applied to a 7-color industrial gravure printing system. The industrial experimental results show that the proposed method features register accuracy to ±0.1mm during the acceleration process without any waste web. Moreover, the proposed feedforward compensation fuzzy PD control is compared with industrial common experience PD control, and the experimental results show that, the absolute maximum register error is reduced from 0.25 mm to 0.08 mm and the average register error is decreased from 0.06 mm to 0.03 mm in the acceleration process. In the final part, the application of the feedforward compensation fuzzy PD control in other printing units in the industrial printing system is revealed. The experimental results indicate that the proposed control approach is effective.