The Research On Tension Control System Of Gravure Printing Machine

Tension system of gravure printing machine is a nonlinear system with variable parameters, the change of this system is very wide, so the author uses frequency conversion motor as its executive body.This object build the model about tension of gravure printing machine according to analyzing the tension of gravure printing machine, establishing tension equation and the model about frequency conversion motor.The first,by making a math analysis about speed loop, using a method that the continuous systems use frequently, using typical-I-systems method, the author has designed the speed loop.The second,taking into account the gravure printing machine having many rolls, difference tension equation about every rolls, so the author analyze the tension loop model for example. The radius of receive roll is mutative, so the model of receive roll is a system with variable parameters, The author calculates the math model about tension loop by assuming the radius of receive roll, fixs the parameters of PID controller by experiment.There are many rolls in gravure printing machine, the speed of these rolls can lead to tension of the system to change, some of these rolls are driven by motor,the other are guide, so in my thesis, I make a research about tension system with three motors for example. Tension system in gravure printing machine has three parts: tension system of requested roll, speed system of guide roll, tension system of given roll. The speed of guide roll is standard speed of system coil stuff.Using fuzzy PID control method instead of tradition PID control because of variable radius of given roll and requested roll, this system can change its PID parameters follow the deviation of tension system. The adaptation of fuzzy PID control is much better than traditional PID control by simulation results in MATLAB, so fuzzy PID control is more suitable in tension of gravure printing machine.The tension system using PLC as a major controller, using PC as a Human-Computer Interaction, using PPI pact as a communicative method complies the tension system and makes the system convenient.