考虑冰风载荷影响的输电线路运行风险评估方法*

Risk assessment method for transmission line operation considering influence of ice and wind loads

摘要:

为预防在极端冰灾环境下大规模停电事故的发生，提出1种考虑冰风载荷的输电线路运行风险评估方法。在极端冰风环境下，计算输电线路与杆塔所承受的总载荷，利用强度与应力干涉模型确定输电线路与杆塔的故障率，同时结合串联可靠性原理确定线路故障综合概率；利用非贯序蒙特卡洛法与线路故障综合概率设置预想故障集，结合直流潮流优化模型计算每条线路的失负荷量；综合考虑负荷等级与抢修恢复时间，确定线路失负荷的经济价值并定义为故障后果；将故障后果与线路故障综合概率的乘积定义为输电线路风险评估指标。以实际拓扑结构修正的IEEE30节点开展算例分析。结果表明：所提方法可对输电线路运行风险进行有效评估。

Abstract:

To prevent the occurrence of large-scale power outages under extreme ice disaster environments,a risk as-sessment method for transmission lines operation considering ice and wind loads is proposed.Under the ex-treme ice and wind environment,the total load borne by the transmission line and tower is calculated,the failure rate of the transmission line and tower is determined by using the strength and stress interference model,and the comprehensive failure probability of the line is determined by combining the principle of series reliability.Use the non-sequential Monte Carlo method and the integrated probability of line failure to set the expected failure set,and combine the DC power flow optimization model to calculate the load loss of each line.The economic value of line load loss is determined and defined as fault consequence by comprehensively considering load level and emergency repair recovery time.The product of fault consequence and line fault comprehensive probability is defined as transmission line risk assessment index.The calculation example analysis is carried out with the IEEE30 node modified by the actual topology structure.The results show that the proposed method can effectively evaluate the operation risk of the transmission line.