基于风险理论的配电网静态安全性评估指标研究

摘要

从配电网供电安全性角度出发,在考虑配电网结构灵活这一特性的基础上,指出配电网静态安全分析需要不同于输电网的安全性评估指标和相应分析手段.以风险理论为基础,结合K(N-1+l)准则和效用理论提出了配电网失负荷风险指标、过负荷风险指标和电压越限风险指标,进而从不同侧面对系统的安全性进行'分诊",并进一步应用层次分析法(AHP)得出系统的总风险指标,作为配电网静态安全分析的基础,以达到"会诊"的目的.还对风险评估方法的应用进行了探讨,并利用算例对不同系统的各项安全指标进行了计算、分析和比较.算例表明提出的配电网静态风险评估方法是可行的,它能够定量地刻画不同假想事故的后果严重程度,准确地反应同一假想事故后不同转供方案下系统安全性的相对高低,为配电网静态安全分析的研究提供了一些有益的参考.%Based on the flexibility of distribution network and starting with power supplying security of distribution network, by comparing distribution network with transmission network, the paper indicates that static security analysis of distribution network needs security indices and analysis method, which is different from that of transmission network.Based on risk theory, it proposes the risk indicators of load loss, overload and voltage limit violation combining with the K(N-1+1) criterion and utility theory.Using this method, the paper gives a sub-diagnosis of the safety for system from different aspects, and makes use of Analytic Hierarchy Process (AHP) to draw the whole risk indicator of system as the foundation of the static security analysis.So we can get the integer indicator of the whole system.The paper also discusses the application of risk assessment, and compares the security indicator of different systems using an example.The example shows that the static risk assessment of distribution network is feasible and can calculate the severity of the consequence of accident quantitatively.This index system can reflect the level of system security, and provide the reference for analyzing static security of distribution network.