Research On Technology Of Isothermal Extrusion Of Aluminum Based On Iterative Learning Control

Iterative learning control (ILC) is accompanied by the application of computer technology gradually developed. Automatic control and artificial intelligence as a combination of a new type of control technology, iterative learning control is well suited for repeated periodic motion characteristics with the controlled system or the controlled object, can effectively achieve a certain time interval with arbitrary precision iterative tracking. Simple and effective control of its advantages, iterative learning control has been more and more attention of researchers, especially in recent years in various fields have a very wide range of applications. Thesis work aimed at achieving the right aluminum extruder outlet temperature of the desired precision tracking, to a large aluminum extrusion machine control system as the control object, research various types of iterative learning control algorithm in its application of the control process.The main contents covered in this paper are as followings:(1) Aluminum and aluminum production process and the development of the industry status quo, citing different models, the tonnage of aluminum extrusion machine, extrusion technology to give its corresponding profile; then summarizes the proposed isothermal extrusion technology and development, wrote a column isothermal extrusion technology, the basic principles and mathematical description, and isothermal extrusion technology at home and abroad to give brief.(2) Discusses the iterative learning control some basic principles, concepts and mathematical description, including the D-type, P-type, PID-type iterative learning law, as well as other open-loop and closed-loop iterative learning control form.For the D-type, P-type, PID-type iterative learning law, as well as other open-loop and closed-loop iterative learning conditions for the convergence of analysis and argumentation.(3) Based on open-loop and closed-loop iterative learning law such as a PID-type iterative learning control systems, and several types of controlled object iterative control simulation of MATLAB, the results show excellent tracking performance.(4) Analysis of isothermal extrusion of aluminum specific process, based on aluminum extruder outlet temperature control mechanism proposed-squeezing power (T-P) mathematical model, and use a complete method of least squares identify the model, a set of the actual production of the new real-time measurement data into the model validation of the (T-P) model can accurately describe the actual production process.(5) Based on open-loop and closed-loop PID-type iterative learning control law for the simplified model for simulation, in the last iteration for the desired trajectory tracking conducted to verify the iterative learning control not only has excellent control performance, but also in the fight against all kinds of interference with strong stability and robustness.The paper based aluminum extrusion machine operation mechanism, identify a simplified outlet temperature-squeezing power (T-P) mathematical model, has finally been based on iterative learning control isothermal aluminum extrusion type control, can effective in the MATLAB environment control of the controlled object to achieve the desired trajectory accurately track the aluminum extrusion isothermal extrusion process optimization and improved control methods with the help of guidance.