Research On Section-drive Multi-motor Synchronous Control System Of Paper Machine

Paper machine is an important study direction for the domain of automation control. With the development of computer control technology, network control technology, intelligent control technology and so on, the automation level of paper machine has been improving. At present, paper machine is moving in large, high-speed, efficient development. The plant of sync-drives control system for paper machine has characteristics of nonlinear and coupling, the complex running environment and many disturbances. So higher accuracy of speed-chain control, tension control and load distribution is needed. Though our paper machine has improved so much, there is a long distance to the best standard in the world. Therefore it is important to solve the key technology issues and develop new automation product with our owned literature privacy for our papermaking industry.This thesis classifies the paper machine control system according to the engineering requirements, studies the drive control system in depth discussion, and points out the development trend and analysis the key and difficult problems of paper machine. Some simulation and experiment were also done to support the study.The multi-motor synchronous control is a problem which needs to be solved urgently in large and medium paper machine. This thesis analyzes the requirements of paper machine in sync-drives control, introduces the auto disturbance rejection controller (ADRC), and improved the current sync-drives control method with ADRC. The speed chain based on ADRC which is applied to solve the problem was proved by simulation. Tension control and load distribution are key and difficult issues too. Their control strategies have been improved with the improving requirements. Their principle, important function and control strategies are analyzed in the thesis. There are three main tension control methods, sensor-based tension control, adjusting roll tension control and sensorless tension control. They have their own advantages. Sensorless tension control was proved by a experiment that it can be used in AC drives. Load distribution can choose torque control based control distribution or speed control based distribution dicided by the type of inverter. After the analysis of theoretical issues on paper machine drive control system, the B&R PCC used as the main controller, a hierarchical distributed contol system was developed for drive control system of 1880 fourdrinier multi-cylinder paper machine. Finally, speed chain, tension control and load distribution were realized by programming to hardware in the laboratory.