中文摘要：

主要研究了一类Roessler原型4系统的Hopf分岔行为及极限环幅值控制问题．首先，利用Hopf分岔理论讨论系统发生Hopf分岔的条件，利用规范形理论判定系统的Hopf分岔类型，并给出极限环幅值算式；然后，对系统施加非线性反馈控制器，判定受控系统的Hopf分岔类型，并给出极限环幅值算式，讨论控制参数对极限环幅值的影响．最后，对讨论结果进行数值仿真，通过理论与仿真结果得出结论：非线性控制器可以改变极限环幅值大小，但不能改变Hopf分岔位置．

英文摘要：

This paper is concerned with Hopf bifurcation analysis and amplitude control of the Roessler prototype-4 system. Firstly, the condition of Hopf bifurcation is dicussed based on Hopf bifurcation theory, and the type of Hopf bifurcation is studied based on normal form, thus the amplitude of limit cycle is obtained by calculation. Then a nonlinear feedback controller is applied to the original system, the type of Hopf bifurcation and the amplitude of limit cycle of controlled system are investigated, and the effect of control parameter on the amplitude of limit cycle is discussed. Finally, numerical simulation results supporting the theoretical analysis are given, the theoretical results and the simulations show that the amplitude of limit cycle of the nonlinear controller can be changed, but the point of Hopf bifurcation can＇t be changed.