电力系统在线暂态稳定分析方法

A Method for On-Line Analysis of Power System Transient Stability

提出了一种电力系统在线暂态稳定分析方法。结合故障时域仿真,建立了一个2维1阶微分方程组。该微分方程组描述了相点在一维坐标轴上的运动,可用于观察电力系统的功角稳定性。在此基础上提出的功角稳定判据可以方便地判断电力系统的功角稳定性。该方法有效地简化了暂态稳定分析过程,且避免了因功角差阈值选取不当造成误判的问题。文中还研究了针对相点运动构造的能量函数,利用故障后的最小动能定义了描述故障严重程度的稳定指标。2007年华北电网的算例说明了上述方法的有效性。

A new method for on-line analysis of power systems transient stability is presented. According to the result of time-domain simulation of fault, a two-dimension first-order differential equation system is established which describes the motion of phase point on tmidimensional coordinate axis, so it can be used to observe the angle stability of power system. On this basis, an angle stability criterion is proposed by which the angle stability of power system can be conveniently judged. The proposed method can simplify the process of transient stability analysis effectively, and the misjudgment due to inappropriate selection of the threshold of angle difference can be avoided. In this paper the energy function that is constructed according to the motion of phase point is studied, and by use of the post-fault minimum kinetic energy the stability index describing the severity of fault is defined. The effectiveness practicability of the proposed method is verified by case study of North China power grid in 2007.