Research And Application Of Model-based Gravure Printing Machine Nonlinear Control

Automatic register control is the core of the whole printers' control system; it is the key factor for deciding the printing precision. Many big disturbance factors will affect the register precision during the process. The whole process is nonlinear at the same time. Thus, high-level controllers are needed. Most of the high-precision automatic register control systems used in the concave printers are imported from abroad. But these control systems are very expensive. Domestic automatic register control systems only satisfy middle and low-level requirements. So developing homemade and high-precision automatic register control system has significant meaning.After deep survey about printing arts on field and reading lots of papers about register control, one basic mathematical model of printers is educed according to theoretic research. Ordinary PID controllers can not satisfy the needs for precise printing because of complexity and nonlearity of printers system. So auto disturbance rejection controller which has nonlinear control structure is introduced. It can overcome the disadvantages of PID controllers such as, contradiction between celerity and overrun, integration saturation and so on. Auto disturbance rejection controller based on models is proposed after combining auto disturbance rejection controller and the model. The compound controller has better performance after simulation and practical application compared with PID controller, ordinary auto disturbance rejection controller, such as good rapidity, little overrun, especially, when the disturbance is big, the stability is rather good.This paper first introduces unwinder, tension control, printing units, rewinder of concave printers in general, and then the core of control system -automatic register control is presented. It contains the correction part and decoupling part. Complete analyzing process for decoupling and correction is presented; subsequently one mathematical model of printers is obtained. It is revised in practice according practical test. After these knowledge, the register controller is put into practice on the basis of B&R's good-performance hardware, controller PCC, servo ACOPOS, human-machine interface POWERPANEL. The practical results are satisfied.