Research On Synchronous Control Of Production Line For Double-shaft Continuous Extrusion Cladding

Double-shaft continuous extrusion cladding is mainly for the production of aluminum-clad cable products.In the actual production line,due to uneven shape of material cross section,and slippage of materials in extrusion wheel,linear velocity of extruding products often fluctuates.Besides,extrusion speed needs to be adjusted according to the different conditions,so it is necessary to keep velocity of pulling products synchronization with the linear velocity.If the pulling speed is too fast,plastic deformation will occur in the aluminum tube even may snap;If too slow,fold of aluminum tube will cause,and wall thickness may be bigger.These will affect the final quality and performance of the coated products.Commonly control way used in the industrial production is PID control,and the traditional PID control is suitable for deterministic control system which can built an accurate mathematical model,besides,the method of parameter setting is complex and the system has poor adaptability to the scene of the actual production.In view of these,use the genetic algorithm combined with PID control for speed control on the tractor.Firstly established control system according to the characteristics of continuous extrusion cladding,and the experimental method was adopted to establish the mathematical model of the system,at the same time combined with industrial commonly used model to calculate the transfer function of the system;Based on genetic algorithm and conventional PID control,genetic algorithm PID control technology was established,using genetic algorithm to optimize PID parameters;Conventional PID control and genetic algorithm PID control were simulated by using MATLAB software,where the unit step response,anti-interference and robust performance were compared respectively.The result of simulation showed that the genetic algorithm PID is better than conventional PID about the effect of control.Using Siemens S7-200 PLC as controller to control the production line;Using PC ACCESS as OPC server,WinCC7.0 used as development platform to build configuration screen for real-time monitoring;PLC and upper computer equipped with WinCC7.0 applied the Ethernet communication mode for data exchange by PC ACCESS;Optimizing program of genetic algorithm was written in WinCC C-script editor,and the optimized PID parameters was transferred to PLC for speed control of tractor,so traction linear velocity and extrusion linear velocity of products would keep matching.After several experiments,the final result showed that this method can realize the on-line intelligent setting of PID parameters,and the control effect is better.