多因子电网冰灾风险评估建模

Modeling for Multi-Factor Risk Assessment on Ice Disaster of Power System

为衡量电网冰灾风险,文章研究了灾害、电网和应急管理对风险的影响,挑选出以下选关键因子:年极值冰厚概率分布、当次冰厚、电网设计冰厚、融冰机台数和资源保障率,建立多因子电网冰灾风险评估模型。皮尔森Ⅲ分布用于体现灾害因素的气候极值,提出了包含融冰机台数影响的单位档距失效率模糊模型,冰灾风险由缺供电量的经济损失风险和修复成本风险构成;建立了应急管理中资源保障率对停电时间影响的模糊模型。某地区电网算例仿真结果表明,投入融冰机和增加电网设计冰厚能够明显地推迟故障,提高资源保障率也能较大程度降低冰灾风险。

To evaluate the power system risk due to ice disaster, the impacts of ice disaster, design parameters and emergency management of power grid on the risk are researched, and five key factors such as probability distribution of annual extremum of ice-thickness, extreme value of a certain ice disaster, the ice thickness specified in the design of power network, the number of de-icing devices and the ratio of guaranteed resources, are chosen to establish multi-factor model to evaluate power grid risk due to ice disaster. The Pearson type III distribution is utilized in climatic extremes to incarnate factors of disaster, on this basis a fuzzy failure rate modes of unit span, in which the impact of the number ofde-icing devices is included, is proposed, and the risk due to ice disaster is composed of the economic loss risk due to the shortage of power supply and the risk due to rehabilitation cost; and a fuzzy model for the impact of the ratio of guaranteed resources in the emergency management on the time of power supply interruption is built. Simulation results of a certain regional power network show that putting de-icing devices into operation and enlarging the specified ice thickness in the design of power network can obviously retard the occurrence of ice disaster and increasing the ratio of guaranteed resources can also lower the risk due to ice disaster considerably.