共查询到19条相似文献,搜索用时 109 毫秒
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在混沌有益时,有目的地产生混沌已经成为混沌学研究的热点问题,本文提出直接延迟反馈实现混沌的反控制,在非混沌系统中产生了混沌.该方法与间接延迟反馈控制方法相比,控制更加简单,更易于实现.该方法与Pyragas提出的延迟反馈混沌控制方法的控制器结构相同,因此,这种直接延迟反馈控制方法可以在需要混沌时产生混沌,不需要混沌时控制混沌,实现混沌控制和反控制的统一,为设计者提供最大的灵活性.针对参数处于非混沌区的Chen系统和Lorenz系统的仿真结果表明了该混沌反控制方法的有效性.
关键词:
混沌
反控制
直接延迟反馈 相似文献
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提出了基于稳定性准则的延迟非线性反馈控制混沌的方法,即SC延迟非线性反馈控制法. 通过对混沌系统的适当分离,得到一个特殊的非线性函数,并利用混沌输出信号与其延迟信号的非线性函数的差,构造了连续反馈输入干扰,以控制混沌轨到某一期望的不稳周期轨上. 该方法继承了延迟反馈控制方法的优点,实现了自-控制过程. 另外由于该方法基于线性系统的稳定性准则,保证了控制的有效性. 控制过程可随时开始,具有简便、灵活性. 给出耦合Duffing振子的例子,数值模拟结果显示了SC延迟反馈方法控制的有效性.
关键词:
稳定性准则
混沌控制
延迟反馈
干扰 相似文献
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参数共振微扰法是一种简单的非反馈混沌控制方法,它十分适合非自治系统的混沌控制.研究了这种方法在电流模式控制Boost变换器混沌控制中的应用,并通过对扰动相位进行优化 ,达到最优的混沌控制结果.同时对参数共振微扰法及其优化方法在Boost变换器混沌控制中的作用进行了理论分析,推导并计算了各种电路参数变化对有效的混沌控制所需的扰动的影响.
关键词:
Boost变换器
混沌
混沌控制
参数共振微扰法 相似文献
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Controlling chaos to unstable periodic orbits and equilibrium state solutions for the coupled dynamos system 总被引:1,自引:0,他引:1 下载免费PDF全文
In the case where the knowledge of goal states is not known, the controllers
are constructed to stabilize unstable steady states for a coupled dynamos
system. A delayed feedback control technique is used to suppress chaos to
unstable focuses and unstable periodic orbits. To overcome the topological
limitation that the saddle-type steady state cannot be stabilized, an
adaptive control based on LaSalle's invariance principle is used to control
chaos to unstable equilibrium (i.e. saddle point, focus, node, etc.). The
control technique does not require any computer analysis of the system
dynamics, and it operates without needing to know any explicit knowledge of
the desired steady-state position. 相似文献
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We demonstrate that chaos can be controlled using multiplicative exponential feedback control. Unstable fixed points, unstable
limit cycles and unstable chaotic trajectories can all be stabilized using such control which is effective both for maps and
flows. The control is of particular significance for systems with several degrees of freedom, as knowledge of only one variable
on the desired unstable orbit is sufficient to settle the system onto that orbit. We find in all cases that the transient
time is a decreasing function of the stiffness of control. But increasing the stiffness beyond an optimum value can increase
the transient time. We have also used such a mechanism to control spatiotemporal chaos is a well-known coupled map lattice
model. 相似文献
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A system of three disk dynamos with six degrees of freedom has been analyzed numerically. It exhibits rich behaviours which are limit cycles, T2-tori and two kinds of chaos. A doubling of T2-torus, frequency lockings and transition from T2-torus to chaos are observed. 相似文献
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E. Gravier X. Caron G. Bonhomme T. Pierre J. L. Briançon 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,8(3):451-457
The various dynamical regimes of collisional drift waves in a magnetized plasma column are experimentally studied. These unstable low-frequency electrostatic waves are related with strong modulations of the ion and electron density. The angular velocity of the rotating plasma column is the control parameter of the dynamics: regular, chaotic and turbulent regimes are obtained. The spatial extension of the system allows for the occurrence of spatiotemporal chaos. The time-delay auto-synchronization method of controlling chaos [K. Pyragas, Phys. Lett. A 170, 421 (1992)] though purely temporal is successfully applied. A numerical study using coupled nonlinear oscillators exhibiting chaos is compared to the experimental results. The control method is tested on this model. 相似文献
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In the preceding paper, we used the mean-field approximation to formulate the time evolution equations for two coupled unidirectional photorefractive ring resonators. Linear stability analysis based upon the steady-state solutions of the mean-field equations showed that the coupled system may become unstable in the unstable off- and steady-state operation regimes. In this paper, we investigate the temporal behavior and nonlinear dynamics of the coupled system. The results indicate that the coupled system exhibits self-pulsation and chaos in the unstable off-state and steady-state operation regimes. The instability is explained in terms of the competition between the nonlinear gain and loss. Numerical results of the transient equations are presented and discussed. The coupling between unidirectional ring resonators is extended to explain the instability in self-pumped phase conjugators. 相似文献
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耦合双稳映象格子模型的时空混沌控制 总被引:1,自引:0,他引:1
变量反馈技术实现了耦合双稳映象格子模型的时空混沌控制.数值实验结果表明,利用不同的反馈技术和不同的反馈强度,可以将双稳映象系统的混沌及耦合双稳映象格子模型的时空混沌控制到不动点或周期轨道.变量反馈控制法除了局域双稳映象系统的定态点外,不需要先获取耦合双稳映象格子时空系统的动力学信息,它对抑制耦合双稳映象系统中的湍流具有一定的指导作用. 相似文献
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Control of chaos via an unstable delayed feedback controller 总被引:7,自引:0,他引:7
Pyragas K 《Physical review letters》2001,86(11):2265-2268
Delayed feedback control of chaos is well known as an effective method for stabilizing unstable periodic orbits embedded in chaotic attractors. However, it had been shown that the method works only for a certain class of periodic orbits characterized by a finite torsion. Modification based on an unstable delayed feedback controller is proposed in order to overcome this topological limitation. An efficiency of the modified scheme is demonstrated for an unstable fixed point of a simple dynamic model as well as for an unstable periodic orbit of the Lorenz system. 相似文献
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声光双稳系统混沌的控制 总被引:8,自引:0,他引:8
对声光双稳系统的混沌态提出参数连续延时反馈的控制技术。数值分析表明,在一定的控制强度下,这种控制使系统在原混沌区具有负的最大李亚普诺夫指数,并且能够保证控制的目标状态是原系统的失稳不动点中稳定周期轨道。文章通过与实验结果的比较,验证了本控制方法的有效性。 相似文献