考虑网络演化的直流潮流停电模型与自组织临界性分析

Analysis on Cascading Failure and Self-organized Criticality in Evolving Power Grids

直流潮流停电(OPA)模型及其改进模型能模拟连锁故障停电过程,并能从宏观上揭示大停电的自组织临界性,但没有考虑电网结构变化对大停电的影响。文中在OPA模型基础上,考虑了慢动态过程中电网结构的演化特征,建立了考虑网络演化的OPA模型。对2个典型复杂网络演化方式的仿真表明:按小世界方式和无标度方式演化的电网都会自组织到临界状态;小世界电网特有的高聚类系数和低特征路径长度易扩大连锁故障的广度和深度,其平均损失负荷大于无标度电网;无标度电网通过小规模的线路连锁开断,释放系统压力,减少大停电概率。研究结果对未来的电网建设及大停电的整体预防有一定指导意义。

Traditional OPA model and its improved models can simulate the cascading failures and reveal the macro-scale of self-organized criticality of the power grid, but lack for considering the effect of the evolvement of topology of the power grid. For the purpose of studying the mechanism of blackouts, an improved OPA model is proposed, in which the structure evolvement of power grid is added to the slow dynamics. Simulation results from two typical complex networks show power grid always organizes itself to criticality in evolving model of small-world network as well as scale-free network. Moreover, from the comparison results between the power grids with two different growth ways, it can be found that the characteristic of small-world power grid makes power loss larger than that in scale-free power grid, and cascading failure in scale-free power grid often lead to lines outage in small scale and ends with little power loss, which can help to release the system stress and decrease the probability of large blackouts. These results can be beneficial in major disturbance mitigation and system planning and upgrading.