为了研究复杂电网连锁故障的传播机理,文中在综合考虑电力系统中过负载故障和隐性故障的基础上,构建了一种基于复杂网络理论的电力系统隐性连锁故障概率模型。该模型假设过负载邻接节点中负载率变化最大的节点和每轮连锁故障中负载波动最大的节点均为隐性故障可能发生节点。将该模型在IEEE300节点网络和Watts—Strogatz网络上进行仿真,仿真结果表明:电力系统隐性故障加剧了故障的传播范围,并且故障传播的范围将随着Watts—Strogatz网络边重连概率的增大而显著增大。最后,指出减小隐性故障的误动概率、降低小世界电网的随机连边概率、防止电网向随机网络演化,是抑制隐性故障在连锁故障中传播、提高电力系统安全性的有效途径。
To analyze the dynamic behavior and the propagation mechanism of cascading failures in complex electric power networks, a novel hidden cascading probability model is proposed, which considers overload faults and hidden faults comprehensively in the electric power system based on the complex network theory. For the overload adjacent nodes in the model, both the nodes whose load change rate is biggest and the nodes whose load fluctuation is biggest in every cascading process are assumed to be the nodes prone to hidden faults. And then the simulations are executed on both the IEEE 300-bus network and the Watts-Strogatz network. The simulation results show that the hidden faults in electric power system can aggravate the spread of the fault, and the spread range of the hidden faults will become appreciably wider with the increment of Watts-Strogatz network reconnected probability. Finally, it is pointed out that the methods of reducing the probability of hidden fault, reducing the edges reconnected probability in the small world network, and preventing power grids from evolving toward the random network, are effective ways to restrain the hidden fault' s propagation in cascading failures, and improve the safe performance of the electric power system.