Aluminum Electromagnetic Continuous Casting And Rolling Of Composite Magnetic Field Optimal Control Strategy Study

The technology of electromagnetic casting-rolling addselectromagnetic field and strong cooling temperature field to the metalsolidification-transmogrification area of casting-rolling, creats thespecial environment, controls the condition of crystal andtransmogrification, products high-powered sheet metal, and a newtechnology with innocuity, low cost. At present, this technology ofAluminum electromagnetic casting-rolling keeps ahead all over theworld.The paper analyses the functional mechanism of electromagneticroll-casting and the forming principle of compound magnetic field. Andbased on the electromagnetic theory, the expression of theelectromagnetic force in the molten aluminium agitated by the travelingmagnetic field was deduced by complex vector method. In order tomatch the requirements, the variable frequency converter which is aAC-AC converter is adopted in the system.Input filters are usually adopted between power and frequencyconverter in the design of main circuit to meet the requirement ofelectromagnetic compatibility(EMC). The design principle of input filterand its affection to input and output performance were discussed, and amodulation method with input power factor correction was presented.In order to solving the system of complicated non-linearity, the badcapability of adaptive, an active disturbance rejection controller-thecontrol system of electromagnetic roll-casting is proposed and realized.On the basis of theoretical research, a prototype of electromagnetic roll-casting compound magnetic field is proposed, including hardware andsoftware design. The hardware design includes the schemes of pulsetrigger, input filter and the control board based on the DSP and CPLD.Aiming at the system real-time commanding, the embeddedreal-time operating systemμC/OS-Ⅱis imported.μC/OS-Ⅱistransplanted to TMS320F2407A DSP according to its characteristics.The interrupt management, multitask based on management and messageexchanging,μC/OS-Ⅱare realized. The flow chart of main tasks are also presented.Finally, this paper makes some conclusions, and presents someissues for future research.