电网复杂性及大停电事故的可靠性研究

从电网连锁故障的近似整体模型的统计分析、动态特点和风险评估入手,探讨了近期关于电网复杂性和连锁故障机理的一些研究进展。众多学者对北美电力可靠性协会(NERC)提供的北美地区15年的事故数据进行分析,发现其事故概率和事故规模近似服从幂指数律,并具有集群特性。学者们提出了多种连锁故障模型来阐释连锁故障的机理。进一步研究发现,电网是一个具有自组织临界特性的网络,其网络演变特性必然导致系统趋向临界状态,而系统临界负荷状态下连锁大停电事故的风险大大增加。要削减和预防电网连锁故障的发生,就需要寻找降低系统风险的作用力, 并建立一个综合评估框架来进行分析和研究。

Survey of the Research on the Complexity of Power Grids and Reliability Analysis of Blackouts

A comprehensive account of a complex systems approach to large blackouts caused by cascading failure is given from the viewpoint of the statistics, dynamics and risk of series of blackouts with approximate global model. According to the analysis of a 15-year record of power outages occurred on the North American power grid provided by NERC, it suggests that the frequency of large blackouts is governed by a power law, and a more reasonable clustering property is also revealed. This result stimulates many theoretical models to come forth which are used to explain the mechanism of cascading of the blackouts in power gird. Moreover, inspired by concepts from self-organized criticality, we suggest that power grid operating margins evolve slowly to near criticality and the critical loads at which blackout risk sharply increase is an vital element to the risk of power system. To mitigate and prevent the blackouts, a new synthetical evaluation framework of power system risk must be established and we should try our best to find the force to reduce the risk of power system.