基于暂态能量裕度的电力系统脆弱性评估  

Power System Vulnerability Assessment Based on Transient Energy Margin

作　　者：卢锦玲[1] 朱永利[1] 

机构地区：[1]华北电力大学电气工程与电子工程学院,保定071003

出　　处：《电工技术学报》2010年第6期96-103,共8页Transactions of China Electrotechnical Society

基　　金：中央高校基本科研业务费专项基金资助项目(09QG060)

摘　　要：电力系统暂态失稳是引发系统灾难性事故的一个重要方面,从暂态稳定角度分析系统的脆弱程度是不可或缺的。电力系统的脆弱水平往往受到天气条件、负荷水平、随机故障的影响,必须合理考虑这些不确定性因素。本文建立了计及气候因素的故障概率模型,提出了从暂态能量裕度角度对电力系统脆弱性进行评估的思想。为避免严重程度高但发生概率小的事故被忽略掉,提出使用概率和能量裕度两个指标来评估系统的脆弱性。借助暂态能量函数定义了事故的能量裕度指标的计算公式,它能反映负荷水平的影响。利用各事故的脆弱性裕度指标还可以识别系统的薄弱环节。借助概率理论和范数理论,利用各事故脆弱性的概率指标和能量裕度指标分别推导出计算整个系统综合脆弱性的概率指标和能量裕度指标的模型,并在此基础上提出了电力系统脆弱性的评估算法。通过算例分析,本文建立的故障概率模型、提出的系统综合脆弱性指标体系以及评估算法是合理有效的。Losing transient stability is an important aspect leading to a disastrous accident in a power system, so analysing power system vulnerability from the viewpoint of transient stability is indispensable. The vulnerability level of a system is often affected by weather condition, load demand level and random faults in the system, so these uncertain factors must be reasonably considered. In this paper, contingent faults’ probability models taking the weather factor into account are set up, and the idea of evaluating a power system’s vulnerability based on the system’s transient energy margin is proposed. In order to avoid a serious fault of smaller occurring probability is ignored, the idea of using both probability index and energy margin index to evaluate a system’s vulnerability is put forward. The formula to calculate the energy margin index of a fault is defined based on the transient energy function, which can reflect the influence of load demand change to the system＇s vulnerability. The weak components in the system can be found by means of energy margin indices relating to faults. Moreover, based on probability theory and Norm theory, the models to calculate compositive probability index and energy margin index of power system are derived. The models’ parameters are probability indices and energy margin indices of all possible faults in the system. Based on the models, an assessing algorithm for a power system vulnerability is proposed. By doing vulnerability analysis of an example power network, the feasibility and effectiveness of the above proposed models and assessing algorithm is proved.

关 键 词：暂态能量裕度 电力系统脆弱性 天气条件 脆弱性指标 范数理论 

分 类 号：TM712[电气工程—电力系统及自动化]