山火条件下特高压直流输电线路合成电场研究

特高压直流输电线路在山火中火焰高温、火焰高电导率、固体颗粒物等因素作用下,容易导致输电线路周围电场发生显著升高,从而引发输电线路跳闸。为此,建立了山火条件下特高压直流输电线路合成电场非线性数学模型,该数学模型能够准确计算输电线路走廊发生山火时是否会引发输电线路跳闸,并以云广特高压直流输电线路为例,采用Comsol软件,分析了山火条件、正常运行条件和饱和电晕条件下地面合成电场。算例计算结果表明,山火条件下地面合成电场可达到正常运行情况下的33.6倍以上。

Study on Synthetic Electric Field of UHV DC Transmission Line under Forest Fire Condition

Under conditions of high flame temperature and conductivity, solid particles in forest fire, electric field around the UHV DC transmission line increased sharply to cause the tripping of transmission lines. Considering forest fire, nonlinear mathematical model of synthetic electric field of UHV DC transmission lines was established, which can accurately calculate whether the transmission line corridor fires may cause tripping of transmission lines or not. Taking Yunguang UHV DC transmission line for an example, software Comsol was used to analyze ground synthetic electric field at the conditions of forest fire, normal operation and saturated corona. The results of example show that under the fire condition, the synthetic electric field can reach about 33.6 times of the normal operation of the situation.