基于事故链风险指标的输电脆弱度在线评估方法

Online Transmission Vulnerability Assessment Method Based on the Fault Chain Risk Index

电力系统中的脆弱输电环节对系统大停电事故有着重要的影响,同时也是动态监测和控制分区策略的重要依据。为了辨识这些脆弱输电环节,在事故链在线生成的基础上,提出了基于事故链风险指标的输电环节脆弱度评估方法。事故链风险由事故链发生概率和产生的后果描述,风险指标综合了造成事故链中间环节触发的各种失效概率和触发后造成系统电压、频率变化和潮流转移的后果函数。根据事故链风险重要度,进一步提出输电环节脆弱度在线评估函数,用以定量分析事故演化过程中较为危险并对电力系统稳定影响较大的输电环节。IEEE39节点系统的仿真结果表明该方法的计算简单有效,有在线应用前景。

Critical segments have serious impact on large scale blackouts and they provide element for dynamic monitoring and emergency control. In order to identify the critical segments, the vulnerability assessment method using fault chain risk index is proposed. The fault chain risk index is described by probability and severity of fault chain. It integrates the various fault probabilities of influencing factors of fault chain segments and severity functions of voltage, frequency and load transfer. On the basis of the fault chain risk, the transmission vulnerability function is proposed to assess the vulnerable degree of transmission segments, which are dangerous and infective. The test on IEEE 39 power system demonstrates the validity and prospect for online application of the proposed method.