Affiliations: [a] Key Laboratory of Industrial Computer Control Engineering of Hebei Province, Yanshan University, Qinhuangdao, Hebei, China | [b] National Engineering Research Center for Equipment and Technology of Cold Strip Rolling, Yanshan University, Qinhuangdao, Hebei, China
Abstract: Bifurcation control for electromechanical coupling torsional vibration
in rolling mill system driven by DC motor is studied in this paper.
Considering the electromechanical devices under unsaturated magnetic
circuit, the dynamical equation of electromechanical coupling
vibration in rolling mill drive system is deduced by using the
dissipation Lagrange equation. Analysing the system equilibrium
point and characteristic roots. Choosing the torsional rigidity of
rotating shaft as a bifurcation parameter and the necessary and
sufficient conditions of Hopf bifurcation are given. The bifurcation
characteristics of the system is investigated and the Washout filter
is adopted to control the Hopf bifurcation, then the effect of the
filter's time constant and the linear gain on the location of
bifurcation point is analyzed. The Normal Form factor is obtained by
using the Direct Normal Form method. It is revealed that, the
nonlinear gain can modify the periodic solution's amplitude and Hopf
bifurcation type. Numerical simulations are also performed, which
confirm the analytical results.
Keywords: Main drive system of rolling mill, electromechanical coupling, Hopf bifurcation, Washout filter, Normal Form
