大干扰下主导低频振荡模式的鉴别

Prony方法是获取系统振荡模式特征的一种非常有效的方法，它可通过给定输入信号下的响应直接估计系统的振荡频率、衰减、幅值和初相位。基于Prony算法，作者提出了振荡模式能量级的概念，用于鉴别电力系统大干扰下的主导低频振荡模式，在8机36节点系统中应用本文所提方法准确识别出了主导低频振荡模式，验证了该方法的正确性，并与正则形理论研究低频振荡模式间的非线性相关作用的结果进行了比较，再次验证了大干扰中主导低频振荡模式对系统动态特性和稳定性有重要影响这一观点的正确性。

Identification of Critical Low Frequency Oscillation Mode in Large Disturbances

Prony analysis is a very useful method to acquire the feature of power system oscillation mode, by which the frequency, amplitude, attenuation, damping and relative phase of the oscillation can be directly estimated through response of given input signals. Based on Prony algorithm a concept of energy class of oscillation modes is proposed to identify the critical low frequency oscillation modes. By means of the proposed method, the critical low frequency oscillation mode in 8-machine 36-bus system under large disturbance is identified accurately, thus the correctness of proposed method is verified. Comparing the obtained result with that from the research on nonlinear interaction among low frequency oscillation modes by normal form theory, the correctness of the viewpoint that critical low frequency oscillation modes under large disturbance greatly affect the dynamic characteristics and stability of power grid is verified once again.