电力系统小干扰稳定分析的最小特征轨迹法

Minimum characteristic loci method for power system small disturbance stability analysis

提出了一种基于Nyquist特征轨迹的多输入-多输出系统小干扰稳定分析方法,可以量化原动机-调速器回路及附加励磁控制回路对稳定裕度的贡献。首先通过框图变换得到了一种便于分析的简洁形式的Heffron-Phillips模型,然后根据广义Nyquist曲线和特征轨迹的关系定义了新的稳定裕度。基于前述模型推导了稳定裕度的线性解析表达式,该线性表达式包含了原动机-调速器回路以及附加励磁控制回路,从而能够清晰地看出二者对稳定裕度的影响。除此以外,所提方法还可以作为控制器参数的设置。最后通过多个算例证明了所提方法的准确性和有效性。

A small disturbance stability analysis method based on Nyquist characteristic loci for multi-input multi-output system is proposed,which can quantify the contributions of turbine-governor loop and additional excitation control loop to stability margin.Firstly,a concise Heffron-Phillips model is obtained through block diagram transformation,and then a new stability margin is defined according to the relationship between the generalized Nyquist curve and characteristic loci.Based on the model mentioned above,a linear analytical expression of the stability margin is derived,which includes the turbine-governor loop and the additional excitation control loop,so that their influence on stability margin can be shown clearly.In addition,the proposed method can also be used as the controller parameter setting.Finally,the accuracy and effectiveness of the proposed method are proved by several cases.