应用功角空间降维变换的相轨迹判别系统暂态稳定性

Transient Stability Detection Using Phase Trajectory Obtained by Dimension Reduction Transform of Power Angles

随着广域测量系统的广泛运用,出现了利用相轨迹几何特征在线判别电力系统暂态稳定性的方法,针对这些方法依赖于分群结果的缺点,该文提出了一种基于功角空间降维变换的相轨迹判稳方法。首先对系统的功角运动轨迹在功角空间中进行降维变换,将轨迹投影为一维坐标轴上的运动,分析了其物理意义;基于这种降维变换后的运动参数,构成新的相平面,并在数学推导证明的基础上利用新的相轨迹凹凸性来判断系统的暂态稳定性。对新英格兰10机39节点系统的仿真实验证明了所提方法的有效性,并指出该方法比普通的分群后直接构成相平面的方法更优越。

With the widespread deployment of wide area measurement system, the method for online identifying power system transient instability according to geometric features of trajectory in phase plane was proposed. The disadvantage of the method is that it is dependent on the clustering results of generators. Given this fact, a transient stability detection method using the trajectory in phase plane obtained by dimension reduction of power angles in power-angle space was proposed. After the dimension of the power angle trajectory was reduced in power-angle space, and the trajectory was projected in a one-dimensional coordinate axis, its physical significance was analyzed. Based on the motion parameters obtained by dimension reduction, a new phase plane was formed. By mathematical deduction, it is proved that the transient stability can be judged by the convexity of trajectory in the new phase plane. To demonstrate the effectiveness of this method, the simulation resutts of the New England 39-bus system were presented. It was shown that this method is better than the method using trajectory in phase plane based on the clustering results of the generators.