Power System Transient Stability Assessment Using Functions Generated by Simulation

电力系统故障引起的暂态现象非常复杂。为了准确地评估它们，必须使用仿真方法。但是，他们有以下问题。(1)为了掌握瞬态现象的整体特征，必须进行大量的模拟案例。(2)仅凭个别模拟案例的结果很难获得评价的整体前景。(3)当仿真条件发生变化时，必须从头进行仿真。本研究探讨了克服上述问题的方法。首先，考虑到暂态稳定主要受故障清除时间和负荷的控制，以暂态稳定这一最重要的特性为评估对象，重新定义了临界故障清除时间函数；其次，提出了利用临界故障清除时间函数评估暂态稳定的方法。最后，将该方法应用于模型电力系统故障暂态稳定性评估。应用结果澄清了以下事实。(1)该方法能准确、高效地评估电力系统暂态稳定性。(2)该方法能准确有效地评估设计因素（如系统构成、设备、控制和保护系统）对暂态稳定的影响。(3)该方法具有以上特点，可用于电力系统的实际规划。

Transient phenomena cased by faults of power systems are very complex. In order to assess accurately them, simulation methods must be used. But, they have the following problems.(1)In order to grasp the whole characteristic of transient phenomena, a great number of simulation cases must be carried out(2)It is difficult to gain the whole prospects of assessment based on results of individual simulation cases.(3)When simulation conditions change, simulation must be carried out from the beginning.This research investigates the method to overcome the above problems. At first, transient stability which is the most important characteristic to assess in power systems is adopted as the object one and critical fault clearing time functions are newly defined by taking notice of the fact that transient stability is mainly controlled by fault clearing time and load Next, the method to assess transient stability using critical fault clearing time functions has been developed. Finally, it has been applied to the transient stability assessment of faults in model power systems. Results of application have been clarified the following facts.(1)This method can accurately and efficiently assess power system transient stability.(2)This method can accurately and efficiently assess the effects of design factors (for examples, system constitutions, equipments, control and protection systems ) on transient stability.(3)This method can be used in the practical planning of power systems, for it has the above characteristics.