【作者】 殷明慧；

【导师】 邹云；

【作者基本信息】 南京理工大学 ， 电力系统及其自动化， 2002， 硕士

【摘要】 经济的发展和技术的进步使得传统电力系统沿着由区域供电向大规模电力系统互联的方向发展，这一发展趋势在带来巨大经济效益的同时也给电力系统的稳定性，尤其是暂态稳定性带来了严重的挑战。直接法是暂态稳定分析的重要方法之一，利用其进行故障后系统的稳定性分析与判定是电力系统研究的一个重要课题。虽然它在过去几十年的已取得了相当大的进展，但是在结构保持模型中的应用以及实际应用等方面仍存在许多问题。此领域内，本文在如下方面展开了研究： 首先，本文分析了结构保持模型中的外部跳变行为，并提出运用BLE方法对外部跳变方向进行判断，这对于获取正确的故障后系统初值是非常重要的。在此基础上，本文将传统Controlling UEP方法拓广至结构保持模型，并提出了新的直接法，扩展Controlling UEP方法。与传统方法相比，它需要进行两次暂态函数值的比较才能给出故障后系统稳定与否的判断，并且有时也给出较为保守的稳定估计。因此，为了提高ECUEP方法的有效性与准确性，本文引入有限的数值仿真代替部分的能量函数值的比较，从而提出了混合ECUEP方法。 其次，本文基于B—H结构保持模型，讨论了TCSC对远距离输电系统的暂态过程及暂态稳定性的影响。仿真结果表明串补度的不同可能会导致系统临界割集的改变。针对这一现象，运用Controlling UEP理论分析表明，TCSC的装设及串补度的变化使得故障后系统相关不稳定平衡点不对应，这解释了临界割集的改变。进一步仿真分析表明过大的串补度会引起支路(割集)暂态能量的不均匀分布，从而可能导致系统暂态稳定性的降低。更多还原

【Abstract】 With the development of economy and the advancement of the technology, the traditional power systems are experiencing a process along the way from the regional power supply to the large-scale connected power systems. This trend brings a great economic benefit, while at the same time, a serious challenge to the stability of the power systems, especially the transient stability. The direct method is one of the most important methods in the transient stability analysis. To Analyze and determine the transient stability of the post-fault system by the direct method is an important task for the research on power systems’ stability. Although great progress has been made over the last decades, there are still many problems to be explored thoroughly, such as applications to the network-preserving model, practical applications and so on. The main research work has been developed as follows:Firstly, this paper analyses the external jump behavior in the network-preserving model and gives the BLE method for determining the direction of the external jump. It is very important to acquire the right initial value of post-fault system. Based on the analysis of the external jump behavior, this paper extends the traditional Controlling UEP method to the network-preserving model and presents the new direct method, Extended Controlling UEP method. Compared with traditional Controlling UEP method, this method needs twice comparation of transient energy value before it identifies whether stability will be maintained or lost. Sometimes it also gives the conservative stability assessments. In order to improve the validity and accuracy of ECUEP method, the Hybrid ECUEP method is introduced.Secondly, this paper discusses the effect of TCSC on the transient process and transient stability based on long distance transmission systems using B-H network-preserving model. The simulation shows that the different series compensation degree will possibly result in the change of the critical cutset. Based on this result, this paper analyzes the reason of the change under the guidance of Controlling UEP theory. The reason is that the Controlling UEPs of different post-fault systems are not corresponding. Moreover the distribution of transient energy on lines (cutsets) will not be even because of too large series compensation degree. This will degenerate the transient stability of power system.更多还原