The Argon Flow Control In The Process Of LF Bottom Blowing Argon

Furnance-LF-Casting has been used by many steel factories. Ladle furnace has been applied widely because of its beteer metallurgical results, wide range of steel application, simple opreation and so on. The bottom blowing argon technology becomes a crucial procedure of Ladle furnace because of its good metallurgical results for instance highly stirring, distributing ingredient and temperature, increasing the rate of chemical reactions, removing inclusions and so on. It is very important to research the argon flow control in the process of bottom blowing argon.The thesis researches the flow control of bottom blowing argon based on LF. First, the mathematical model is established. It is very difficult to establish it by using mechanism method because LF bottom blowing argon system is very complicated. So the test method is used to determine the mathematical model of bottom blowing argon system. By analyzing the structure of bottom blowing argon system and the situation under the present control method, LF bottom blowing argon system is designed. Bottom blowing argon is a system with time-varying parameters and nolinear hysteresis and big inertial. So Smith prediction control method which has the compensation to hysteresis is used to design bottom blowing argon controller. Because the model is gotten by the test method. It has indeterminacy and error. In order to overcome the weakness of Smith prediction which is sensitive to the model error, a betrer Smith predict control is advanced to design the LF bottom blowing argon. It can realize the good control to the bottom blowing argon system.Finally, the author uses the Simulink in MATLAB to build the simulation structure of system. The results show that the better Smith prediction control can solve the control hysteresis and overshooting in the process of LF bottom blowing argon and it can meet the control demands better to provide an effective protection for the flow control of blowing argon.