磁暴在单回交流输电线中感应电流的验证计算

Verification of Induced Currents in Single Return AC Transmission Line during Geomagnetic Storm

准确计算磁暴期间交流电网中的地磁感应电流(geomagnetically induced current,GIC)对评估磁暴对交流电网的影响至关重要。在研究磁暴对交流电网的影响时所应用的现有模型的基础上,以单回交流输电线为研究对象,将交流输电线、接地体和大地进行统一建模;并采用有限元法(FEM)进行求解。这种新模型既可以处理电导率复杂分布的大地模型,又可以将交流输电线及接地体对地表感应地电场分布的影响考虑在内。均匀选取磁暴期间地磁场变化频率0.000 1~0.1 Hz之间的特定频点,分别采用现有模型和新模型计算交流输电线中的GIC,通过对比验证,表明现有模型在频率0.000 1~0.1 Hz之间计算磁暴期间交流电网中GIC时是适用的。

Accurate calculation of geomagnetic induction current( geomagnetically induced current,GIC) in AC power grid during geomagnetic storms is crucial for assessing the impact of geomagnetic storms on AC power grid. Based on the existing models applied the impact of magnetic storms on AC power grid,take single return AC transmission line as the object,unified model of AC transmission lines,grounding bodies and earth,and the finite element method( FEM) is used to solve the problem. The new model can not only deal with the earth model with complex conductivity distribution,but also take into account the influence of AC transmission line and grounding bodies on the ground electric field distribution induced by geomagnetic storms. By using the existing model and new model,the GIC of AC transmission line is calculated at the specific frequency point between the frequency of0. 000 1 ~ 0. 1 Hz,by comparison and verification,it is shown that the existing model is applicable to calculating the GIC in AC power grid during geomagnetic storms between the frequency of 0. 000 1 ~ 0. 1 Hz.