冲击接地电阻模型对输电线路耐雷水平的比较研究

Study on Impulse Grounding Resistance Model to Lightning Withstand Level of Transmission Line

对规程法冲击接地电阻模型、火花效应接地电阻模型以及暂态接地电阻模型等三种不同的接地模型进行了分析。结合220 kV双回输电线路,在ATP/EMTP中建立了相应的输电线路耐雷水平模型。在该耐雷模型中,使用无损多波阻抗模拟输电线路杆塔,同时考虑了工频电压对耐雷水平的影响。分别在工频电压初相角为0°、60°、120°、180°、240°以及300°等6种情况下计算了模型的反击和绕击耐雷水平。仿真结果表明:在相同的条件下,反击耐雷水平从高到低依次为火花效应模型、规程法模型、暂态电阻特性模型,而这三种接地模型下的线路绕击耐雷水平一样。随着电源初相角的改变,输电线路耐雷水平也随之发生相应改变。

Impulse grounding resistance has a big impact on transmission line lightning withstand level. Three models of the impulse grounding resistance such as procedure method model, spark discharge model and transient resistance model are discussed. Combined 220 kV double transmission lines, a model of transmission line lightning withstand level in ATP/EMTP is made, in which lossless multi-wave impedance is used to simulate transmission line tower, and the effect of power voltage is also considered. Respectively, the initial phase of 0°,60°,120°,180°,240°and 300°, etc., is considered to calculate the lightning withstand levels of counterattack and shielding failure. It is shown that under the same conditions, the counterattack withstand level from high to low in turn, the order is spark discharge model, procedure method model, transient resistance model. The shielding failure lightning level of these three models is almost the same. With the change of the initial phase of power voltage, the withstand level also change accordingly.