基于线路运行可靠性模型的电力系统连锁故障概率评估

Cascading Failure Probabilistic Assessment of Power Systems Based on Operational Reliability Model for Transmission Lines

线路过载被认为是致使连锁故障进一步发展的主要原因。文中基于输电线路的运行可靠性模型,计算了反映系统运行状态的连锁故障风险指标。采用递归算法生成连锁故障树,记录连锁故障路径经历的每个状态及其相应的连锁故障风险指标。在运行可靠性评估框架的基础上,结合动态潮流计算,对IEEE RTS系统进行了连锁故障运行可靠性评估。分析了不同线路额定传输容量和负荷水平对该系统连锁故障风险的影响。计算结果表明,所提出的连锁故障风险指标能够较真实地反映系统状态和可能存在的薄弱环节,且能够向调度员提供预警信息。

Overload of transmission lines is considered as one of the most important factors which results in iurther deterioration of the cascading failures in power systems. Therefore, based on the failure probability model for transmission lines, the risk indices of cascading failures which reflect the operating state of the system is calculated. A recursive algorithm is used to＇build the cascading failure tree which can record every state on cascading failure path and its relevant risk indices. Based on tile operational reliability evaluation framework, combining with dynamic power flow calculation, a cascading failure operational reliability evaluation is carried for IEEE RTS test system. The risk indices of cascading failures under different transmission line rating capacities and load levels are calculated respectively. The calculation results illustrate that the indices can reflect the real system state and provide operators with early warning information which points out the weakness of the power system.