电力系统频域电压稳定测度的研究

STUDY OF POWER SYSTEM VOLTAGE STABILITY PROXIMITY INDICATION IN FREQUENCY DOMAIN

传统的电压稳定测度指标都把潮流方程雅可比矩阵奇异点作为系统电压失稳的临界点，而不考虑系统发生Ｈｏｐｆ分叉的可能性，因而使得相应的测度指标不可避免地具有一定的冒进性。文章利用Ｌａｐｌａｃｅ变换，提出了一种基于雅可比矩阵修正模型的电压稳定性频域测度。该测度是对以潮流方程雅可比矩阵奇异为前提所提出相应测度指标的修正，可同时计及系统发生Ｈｏｐｆ分叉和鞍点分叉的可能性。两个算例系统的计算表明，它具有较好的线性特性，因而对系统失稳的临界点具有较好的预见性。

Almost all proximity indictors of traditional power system voltage stability treat voltage stability critical point as the saddle node bifurcation point, while the Hopf bifurcation point is paid no attention to. Therefore, they are somehow optimistic in applications. In this paper, based on the modified Jacobian matrix model, an indictor in frequency domain is presented. It can be used to measure the proximity to voltage instability which is indicated by either Hopf or saddle node bifurcation. The results of two example power systems show that the proposed indictor can approach nearly 'linearly' to zero in a wide interval around the system critical point.