考虑故障不确定性和保护动作性能的电网连锁故障模式搜索

电网连锁故障可能导致大规模停电事故并造成严重后果.由于电网的故障模式较多,故障参数(包括各种连续参数和离散变量)形式各异,且搜索连锁故障需要模拟保护动作性能和紧急控制措施,因此连锁故障模式的搜索和后果分析十分困难.文章综合确定性和概率分析方法的优点,提出了利用混合方法搜索连锁故障模式,由人工指定系统的原发性短路故障,随机抽样确定故障参数和保护动作的特性,考虑多种紧急控制措施和由于故障线路切除后潮流转移造成的过负荷保护动作,交替执行稳定和潮流计算,自动快速筛选出后果严重且较易发生的连锁故障模式.对IEEE-RTS系统的计算结果显示了本文方法具有良好的在线应用前景.

SEARCH OF POWER SYSTEM CHAINED FAILURE MODE CONSIDERING UNCERTAINTY OF ELEMENT FAULT AND PERFORMANCE OF PROTECTIVE RELAYING

Chained failures may cause large scale blackout and lead to serious consequences. Because there are many kinds of fault modes occurred in power network and the parameters of the faults, including various continuous parameters and discrete variables possessing different forms, and it is necessary for searching chained failures to simulate the action of protective relayings and emergency control measures, therefore, it is rather difficult to search the modes of chained failures and analyze the consequences. Synthesizing the advantages of certainty and probabilistic analysis, it is put forward to search the chained failure modes by mixed method, that is, artificially specifying the primary short circuit fault, the fault parameters and the action features of the protective relayings are determined by random sampling. Considering the actions of various emergency control measures and the protective actions for the overload caused by power flow transferring after the faulty line is disconnected, the system stability and power flow should be alternatively calculated. Then the chained failure mode which easily takes place and may cause serious consequence can be automatically and quickly screened out. The calculation results of IEEE-RTS system show that the on-line application of this method is available.