Research And Design On The Autoleveller Control System In The Nonwoven

Nonwoven is one of today's fast-growing industries, which does not need fabric weaving and spinning, with simple process, high productivity; fast production speed, high output; a wide range of fibers to applied; kinds of processes, wide ranges of uses.Evenness is an important index of the nonwoven product quality, which has a direct impact on the product performance and the subsequent processing of end-use performance. Autoleveller has a great impact on the nonwoven evenness, but up to now, the study for the nonwoven autoleveller in China is far behind that in foreign countries.This project makes research and design for the nonwoven autoleveller on the basis of the nonwoven autoleveller made in China. Firstly, we analyze nonwoven equipment and process, and then make its maths model by means of autoleveller theory. Secondly, we set up nonwoven autoleveller DCS, combined with modern computer control technology and DCS. Thirdly, we propose nonwoven evenness control technology based on fuzzy-PID, and design an autoleveller control system. This research has a certain help for our nonwoven auotleveller made in China, and it is also a new try.(1)Research on the basis of model of nonwoven processNow the nonwoven evenness is not very satisfactory. Although some progresseshave been made by means of improving to the crosslapper process, the best effect cannot be reached. In this paper, the model on the carding machine is made, the way to control fiber CD direction evenness by changing the doffer's speed is proposed, and nonwoven autoleveller control system in the way of open loop and close loop combined is constructed to assure evenness by means of research on the nonwoven process.(2)Design of nonwoven autoleveller on the basis of Distributed Control SystemSIEMENS PCS 7 is chosen as control system on this subject to constructnonwoven DCS autoleveller control system by the study on the DCS. Experiment result shows that the control system based on the former theory has a great effect on improving nonwoven evenness.(3) Research on the nonwoven evenness control based on fuzzy-PIDBased on traditional PID control and fuzzy control theory introduced, and theirshortcomings analyzed. We introduce nonwoven autoleveller control technology based on fuzzy-PID. Simulation result shows that fuzzy-PID has better dynamic and static performance than traditional PID.