节点势能架构下的电压脆弱性评估

Voltage Vulnerability Assessment in the Node Potential Energy Framework

考虑到系统电压主要受无功影响的特点,从节点势能的角度提出电压脆弱性评估方法。该方法以无功负荷、发电机无功出力、无功补偿等不同无功注入成分变化下的势能裕度为基准,根据通常的电压稳定指标和电压脆弱性的定义推导不同无功注入成分影响下的电压脆弱性评估的程度指标及趋势指标,探讨网络拓扑结构和无功注入成分变化下电压脆弱性评估指标的获取。该方法的优势是能统一量化节点电压在系统不同无功注入成分变化影响下的演变过程,并准确确定系统最薄弱点。在IEEE-30母线系统中的仿真结果及其与基于连续潮流法的传统电压稳定指标仿真结果的对比,验证该方法的有效性和可行性。

Considering the fact that the voltage is mainly influenced by reactive power, a method is proposed to assess voltage vulnerability. In this method, the potential energy margins, which were influenced by the different factors related to reactive power （such as reactive load, reactive production of generator and reactive power compensation） were first computed as the base values. And then, based on the common voltage stability index and the definition of voltage vulnerability, the assessment indexes were founded and discussed under the impacts of the different reactive power related factors and the network topology. Moreover, what needs to be emphasized is that the indexes can uniformly quantify the voltage profile with the changing of reactive power related factors and even identify the vulnerable region exactly. At last, comparing with the common assessment index calculated by continuous power flow （CPF）, the simulations results of this method in IEEE-30 bus system prove its validity and feasibility.