Chin. Phys. B Vol. 23, No. 10 (2014) 104502
Hopf bifurcation control for a coupled nonlinear relative
rotation system with time-delay feedbacks
∗
Liu Shuang(刘 爽)
a)b)
, Li Xue(李 雪)
a)
, Tan Shu-Xian(谈书贤)
a)
, and Li Hai-Bin(李海滨)
a)†
a)
Key Laboratory of Industrial Computer Control Engineering of Hebei Province, Yanshan University, Qinhuangdao 066004, China
b)
National Engineering Research Center for Equipment and Technology of Cold Strip Rolling, Yanshan University, Qinhuangdao 066004, China
(Received 15 March 2014; revised manuscript received 11 April 2014; published online 20 August 2014)
This paper investigates the Hopf bifurcations resulting from time delay in a coupled relative-rotation system with time-
delay feedbacks. Firstly, considering external excitation, the dynamical equation of relative rotation nonlinear dynamical
system with primary resonance and 1:1 internal resonance under time-delay feedbacks is deduced. Secondly, the averaging
equation is obtained by the multiple scales method. The periodic solution in a closed form is presented by a perturbation
approach. At last, numerical simulations confirm that time-delay theoretical analyses have influence on the Hopf bifurcation
point and the stability of periodic solution.
Keywords: relative rotation, coupled nonlinear system, bifurcation, time delay
PACS: 45.20.dc, 05.45.–a DOI: 10.1088/1674-1056/23/10/104502
1. Introduction
The study of rich nonlinear behaviors such as bifurca-
tion and chaos has become an important component in the
field of nonlinear system. The research on nonlinear behav-
iors can be found in dynamical system,
[1–3]
neural network
system,
[4–6]
financial system,
[7,8]
and biological system,
[9–11]
etc. The time delay, as a kind of basis nature of the physical
phenomenon, has a great influence on those rich nonlinear be-
haviors of nonlinear system.
[12–14]
For an SIS (Strategic Infor-
mation System) epidemic model
[15]
with time delays, the in-
fluence of time delay on the stability of equilibria is displayed.
The action of time delay in a non-autonomous system
[16–18]
is investigated. It is obtained that time delay may be used as
a simple but efficient ‘switch’ to control motions of a system.
There are many remarkable studies focusing on nonlinear be-
haviors control by using time delay. The band of the satura-
tion control in an auto-parametric dynamical system is inves-
tigated by using the linear delayed feedback.
[19–22]
Consider-
ing a forced Holmes–Duffing system, the effects of linear de-
layed velocity feedback on controlling the fractal eroded safe
basin are investigated.
[23]
The nonlinear delay feedback is ap-
plied to move the critical bifurcation point and stabilize the
periodic solution in a relative rotation system.
[24]
Although
many remarkable studies on uncoupled nonlinear system have
been done as mentioned above, researches on the nonlinear
delayed feedback control in nonlinear coupled systems have
rarely been proposed. The rolling mill system is a represen-
tative mechanical coupled dynamic system and a multi-degree
of freedom system in actual industrial production. Many re-
markable studies on uncoupled nonlinear system of rolling
mill with two masses have been done.
[25,26]
Wang et al.
[27]
investigated the time-delay neural network with two masses
and chaotic control of the complex networks by the method
of Open Plus Nonlinear Closed Loop (OPNCL) and the Time-
Delay Feedback Control (TDFC) respectively. However, the
researches on those dynamical equations with two masses are
not applied to the actual well in work conditions of multi-
degree of freedom. Therefore, in order to analyze thermody-
namical characteristics of this kind of multi-degree of freedom
system completely and effectually, we intend to apply a non-
linear time delay to the coupled system with three masses to
create a Hopf bifurcation and control the stability of periodic
solutions. The research results provide a theoretic basis and
a reference for suppressing torsional vibrations of the rolling
mill caused by nonlinear time delay. This paper is organized
as follows: The dynamical equation of the nonlinear coupled
relative rotation system of a three-mass rolling mill is estab-
lished in Section 2. With the application of the perturbation
technique, averaging equations of coupled system with pri-
mary and 1:1 internal resonances are presented in Section 3.
Section 4 outlines the effect of time-delay parameters on the
creation and stability of Hopf bifurcation. Numerical simula-
tions are performed to verify the analytical results in Section 5.
Finally, conclusions are given in Section 6.
2. Coupled nonlinear relative-rotation system
Considering a relative rotation system of a three-mass
rolling mill, the total kinetic and potential energy of the system
∗
Project supported by the National Natural Science Foundation of China (Grant No. 61104040) and the Natural Science Foundation of Hebei Province, China
(Grant No. E2012203090).
†
Corresponding author. E-mail: hbli@ysu.edu.cn
© 2014 Chinese Physical Society and IOP Publishing Ltd http://iopscience.iop.org/cpb http://cpb.iphy.ac.cn
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