山火条件下的架空输电线路停运概率模型

A Probabilistic Model of Overhead Transmission Line Outage due to Forest Fire

由于输电走廊经常经过山区、农区等山火易发地带,山火已对输电线路可靠性产生重要影响。目前考虑山火状况对输电线路可靠性模型方面的研究较少,为此,以山火地表火行为数理模型为基础,将模型得出的山火状况作为输入量,引入输电线路可靠性计算中。基于山火导致输电线路空气间隙被击穿的原因,建立了相应的停运概率模型,预测相地放电与相间放电2种情况的停运概率。算例计算了某山火发生后将影响到线路运行的时间,并给出了典型的输电线路在不同山火状态下的停运概率,结果表明模型能够正确反映山火对输电线路可靠性的影响。

Some overhead transmission corridors pass through fire-prone regions such as mountain and rural areas, and forest fire greatly affects on transmission line reliability. At present, in the research on reliability model of overhead transmission line the condition of forest fire is seldom taken into account. Utilizing mathematical model of surface fire behavior caused by forest fire, the forest fire conditions obtained from this model are taken as input variables and led into the computation of reliability of overhead transmission line. Based on the reasons causing breakdown of air gap of overhead transmission line, corresponding probabilistic model of overhead transmission line outage is built, in which the air gap breakdown mechanism under forest fire is considered, to predict the outage probability due to phase-to-ground discharge and that due to phase-to-phase discharge. In case studies the affected times of overhead transmission line operation after the occurrence of forest fire are calculated and the outage probabilities of typical overhead transmission line under different forest fire conditions are given. Calculation results show that the proposed model can reflect the affect of forest fire on overhead transmission line reliability correctly.