Analysis And Control Of Dynamic Behavior Of Main Drive System Of Rolling Mill

Main drive system is an important part of rolling mill.The torsional vibration phenomena occurring in frequently rolling mill working processes will reduce the steel products' quality and yield efficiency,even destory the rolling equipments.The main drive system of rolling mill is composed of electric drive control system and mechanical transmission system.This topic regards the main drive system of rolling mill as the research object,and consider the coupling effect of electromagnetic parameters and mechanical parameters,then we get the nonlinear torsional vibration model.From the angle of electromechanical coupling,the nonlinear dynamic behavior of system instability is studied,and the nonlinear controller is designed by using the exact feedback linearization method.Firstly,consider the effects of system structure parameters(coupling effects of mechanical and electrical parameters),external disturbance and other factors.The nonlinear dynamical equation of electromechanical coupled torsional vibration system was built based on the Lagrange principle of generalized dissipative system.Secondly,the dynamic behavior of the electromechanical coupling system of the rolling mill main drive is analyzed.With the numerical analysis method,when the load amplitude decreases with the time change,the bifurcation diagram and the largest Lyapunov exponents of the system are obtained.By making the phase plane diagram,the Poincare section map,the time history diagram of the nonlinear system under one load amplitude,the motion state of the system is judged.At last,the controller of nonlinear system is established by using the method of accurate feedback linearization.Under the action of the controller,the system is changed into stable motion from the original chaotic motion.In the process of establishing the nonlinear controller,the system is linearized,but the process does not ignore any nonlinear term of the system.So it has a high precision.