Research On Distributed Control Design And Sliding Mode Control For Vibration Displacement System Of Continuous Casting Mold

Continuous casting process is an important link in steelmaking.In order to ensure the efficiency of steelmaking and the quality of cast slabs,the production mode of multi-strand is usually adopted in practice,and the mold in each continuous casting strand is required to vibrate according to a given vibration waveform.The key to ensure the quality of slab is that the mold can track the desired displacement curve.Multi-strand continuous casting has higher requirements on the safety and reliability of the system.In addition,uncertainty disturbance in the system will affect the tracking effect of displacement.With the aim of ensuring the safety and stability of multi-strand production,and ensuring that the mold accurately track its desired displacement,the distributed control design and sliding mode control research are carried out.The main research work is as follows:Firstly,in view of the problem of insufficient safety and reliability of centralized control mode,a design scheme of mold vibration distributed control system is proposed.Each continuous casting strand in this scheme is individually controlled by a Siemens high-performance motion controller SIMOTION D425.The continuous casting strands are independent of each other,so as to avoid the situation that affect the production of all strands due to the failure of some part of the central controller and improve the safety and reliability of the system.Secondly,taking one of the multi-strand as an example,the mathematical model of the system is established.Aiming at the problem that the output equation of the continuous casting mold vibration displacement system is a nonlinear equation,which is not conducive to the design of the displacement tracking controller,a nonlinear processing algorithm is proposed to facilitate the follow-up displacement tracking control research.Thirdly,for the mold vibration system with disturbances such as model uncertainty and the initial deviation of the eccentric shaft zero position,the simplified model of the system is obtained by equating the servo motor speed closed-loop control system as a second-order oscillation link.By combining the homogeneous continuous control law and the adaptive super-twisting sliding mode control law,an adaptive high-order sliding mode controller is designed to achieve tracking of the expected displacement of the mold.Finally,aiming at the problem of large and fast time-varying load interference in the mold vibration system,the load disturbance is estimated in real time by designing an observer and its value is compensated to the controller to enhance the anti-interference performance of the system and improve the displacement tracking accuracy.