基于支路模式振荡能量的低频振荡区域定位方法

Low-frequency Oscillation Area Location Method Based on Branch Mode Oscillation Energy

电力系统发生低频振荡时,参与振荡的机组通过网络中的支路交换振荡能量,故支路上蕴含丰富的振荡信息。针对系统不同模式下振荡区域的识别问题,该文提出一种基于支路模式振荡能量的低频振荡区域定位方法。首先,在推导满足能量守恒定律的电力系统能量函数基础上,定义从网络角度研究系统振荡规律的支路振荡能量;解析发现支路振荡能量由多个支路模式振荡能量叠加而成,并提出多模式下支路模式振荡能量的提取方法;随后,通过理论推导建立支路模式振荡能量与发电机状态变量之间的解析关系,为采用支路模式振荡能量研究低频振荡问题奠定了基础;最后,建立基于支路模式振荡能量的低频振荡区域定位方法,并通过仿真分析验证了该方法的有效性。

When low-frequency oscillations occur in a power system,the oscillating generators exchange oscillation energy through the branches in the network,so the branches contain rich oscillation information.Aiming at the problem of identifying the oscillation region in different modes,a low-frequency oscillation region location method based on the branch mode oscillation energy is proposed in this paper.First,on the basis of deriving the power system energy function satisfying the law of energy conservation,the branch oscillation energy is defined to study the system oscillation law from the perspective of network.It is found that the branch oscillation energy is superimposed by several branch oscillation modes,and a method for extracting the branch oscillation energy in multiple modes is proposed.Then,the analytical relationship between the branch mode oscillation energy and generator state variables is established through theoretical derivation,which lays a foundation for the study of low-frequency oscillation problems by using the branch mode oscillation energy.Finally,a low-frequency oscillation region localization method based on branch mode oscillation energy is established,and the effectiveness of the method is verified by simulation analysis.