考虑负荷时序特性的含主变配电网可靠性评估

摘要

针对现有配电网可靠性评估方法主要对不同电压等级进行独立评估,且未考虑实际电网运行过程中负荷的时序变化特性等问题,提出了一种高配电自动化水平下,考虑负荷时序特性的含主变配电网可靠性评估方法.首先,基于分区化简方法对中压配电网进行故障分析,确定多联络下基于负荷均衡度的分区转供模型;其次,提出了高配电自动化水平下主变故障后以最小隔离区为单位的负荷转供策略,并分析了考虑备自投的主变故障协同处理过程;最后,结合元件停运与负荷时序模型,提出了含主变的配电网可靠性评估序贯蒙特卡洛模拟流程.算例表明,所提方法更符合电网未来的运行实际,评估结果更加全面准确.%To solve the problem that the existing distribution network reliability assessment methods mainly evaluate dif?ferent voltage levels independently and do not consider the time-varying characteristics of loads during the actual opera?tion of the power grid,a method of reliability assessment on the distribution network with a main transformer is pro?posed considering the load timing characteristics under a high distribution automation level.First,based on the parti?tion reduction method,the fault analysis of medium-voltage distribution network is carried out to determine the district transfer model with multiple connections based on a load balance principle.Second,under a high distribution automa?tion level,a load transfer strategy is proposed after the fault of the main transformer,which adopts the minimum isola?tion zone as unit,and the main transformer fault coordination process is analyzed considering automatic bus transfer.Fi?nally,combined with the models of component outage and load timing,a sequential Monte Carlo simulation flow of the reliability assessment on the distribution network with a main transformer is proposed.A numerical example shows that the proposed method is more in line with the actual operation of the power grid in the future,and the assessment results are more comprehensive and accurate.