电力系统静态电压稳定性在线监控(一)——一种可在线应用的计及负荷静态特性的电压稳定指标  

On-line voltage stability monitoring for electric power systemPart 1:On-line voltage stability index consideringload static characteristics

作　　者：傅旭[1] 王锡凡[1] 

机构地区：[1]西安交通大学电气工程学院,陕西西安710049

出　　处：《电力自动化设备》2005年第8期23-26,31,共5页Electric Power Automation Equipment

基　　金：国家重点基础研究专项经费项目(2004CB217905)~~

摘　　要：基于局部量测数据和负荷静态特性,提出了一种可在线应用的节点静态电压稳定指标。首先介绍了ZIP负荷模型,然后用戴维南等值电路简化系统,将线路电流表达式整理成实部和虚部,消去负荷有功后代入ZIP负荷模型中的无功表达式得二次方程式,用根判别式得到以无功表示的电压稳定指标VSIQ;同理得以有功表示的电压稳定指标VSIP;取两者中的较小值作为节点电压稳定指标VSI。比较各节点VSI,最小值对应的节点即为系统最薄弱节点。以IEEE14节点和IEEE30节点系统为例,仿真系统在不同负荷特性下VSI的变化曲线。结果显示:恒定功率分量所占比例越大则节点VSI越小,电压稳定性越差;恒定功率比重相等情况下,恒定电流分量比重越大,节点电压稳定性越差。Based on the load static characteristics and local measurements,a new index for on-line static voltage stability analysis is proposed.The ZIP load model is introduced and the equivalent line current is divided into real and imaginary parts based on Thevenin equivalent circuit.After eliminating the active power and substituting the reactive power of ZIP load for the imaginary part,a quadratic is obtained,which is processed by the root discriminant to deduce a voltage stability index VSIQ.Similarly,eliminating the reactive power,VSIP is derived.The smaller of VSIQ and VSIP becomes the bus voltage stability index VSI and the bus with the smallest VSI is the weakest one of system.The proposed index is tested on IEEE 14 - bus and IEEE 30 - bus systems,and the simulative results indicate that,the more the percentage of constant power is,the smaller the VSI will be.When the percentage of constant power is identical,the more the percentage of constant current is,the smaller the VSI will be.

关 键 词：电压稳定 节点电压稳定指标 负荷静态特性 

分 类 号：TM712[电气工程—电力系统及自动化]