Geomagnetically Induced Current Model Validation From New Zealand's South Island
Geomagnetically Induced Current Model Validation From New Zealand's South Island
复制标题
新西兰南岛的地磁感应电流模型验证
DOI：
10.1029/2020sw002494
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发表时间：
2020
期刊：
影响因子：
3.7
通讯作者：
Divett T
中科院分区：
文献类型：
--
作者：
Divett T
空间天气事件期间的地磁感应电流(GIC)此前曾在新西兰造成变压器损坏。在2015年圣帕特里克节风暴期间，TRANSPOWER新西兰有限公司对新西兰南岛的23台不同变压器进行了可靠的GIC测量。这些观测到的GIC在空间上和变电站内显示出很大的变异性。我们将这些GIC与使用具有行业提供的线路、接地和变压器电阻的输电网络的网络模型根据建模的地电场计算的GIC进行比较。我们使用薄片模型，根据风暴期间测量的磁场变化频谱和地面电导计算了模拟的地电场。对于23台变压器中18台的大多数有效频率，建模和观测的GIC谱相似，相干超过95%的置信度阈值。敏感性分析表明，模拟的GIC对磁场输入的变化最敏感，其次是陆地电导率的变化。假设输电线路沿着直线，或者让网络电阻完全正确，这种假设就不那么重要了。将模拟的GIC时间序列与测量的GIC时间序列进行比较，表明该建模方法对于重建突然开始和亚暴期间GIC峰值的时间、持续时间和相对大小是有用的。然而，该模型严重低估了这些峰值的大小，即使对于具有良好光谱匹配的变压器也是如此。这是因为薄片模型适用的频率范围有限，严重限制了这种建模方法对GIC峰值的准确预测的有用性。
Geomagnetically induced currents (GICs) during a space weather event have previously caused transformer damage in New Zealand. During the 2015 St. Patrick's Day Storm, Transpower NZ Ltd has reliable GIC measurements at 23 different transformers across New Zealand's South Island. These observed GICs show large variability, spatially and within a substation. We compare these GICs with those calculated from a modeled geolectric field using a network model of the transmission network with industry‐provided line, earthing, and transformer resistances. We calculate the modeled geoelectric field from the spectra of magnetic field variations interpolated from measurements during this storm and ground conductance using a thin‐sheet model. Modeled and observed GIC spectra are similar, and coherence exceeds the 95% confidence threshold, for most valid frequencies at 18 of the 23 transformers. Sensitivity analysis shows that modeled GICs are most sensitive to variation in magnetic field input, followed by the variation in land conductivity. The assumption that transmission lines follow straight lines or getting the network resistances exactly right is less significant. Comparing modeled and measured GIC time series highlights that this modeling approach is useful for reconstructing the timing, duration, and relative magnitude of GIC peaks during sudden commencement and substorms. However, the model significantly underestimates the magnitude of these peaks, even for a transformer with good spectral match. This is because of the limited range of frequencies for which the thin‐sheet model is valid and severely limits the usefulness of this modeling approach for accurate prediction of peak GICs.
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新西兰的长期地磁感应电流观测：地球返回修正和地磁场驱动器
影响因子：
3.7
作者：
D. H. Mac Manus;C. Rodger;M. Dalzell;A. Thomson;M. Clilverd;T. Petersen;Moritz M. Wolf;N. Thomson;T. Divett
通讯作者：
T. Divett
DOI：
10.1002/2017sw001602
发表时间：
2017-10
期刊：
Space Weather
影响因子：
--
作者：
M. Butala;M. Kazerooni;J. Makela;F. Kamalabadi;J. Gannon;Hao Zhu;T. Overbye
通讯作者：
M. Butala;M. Kazerooni;J. Makela;F. Kamalabadi;J. Gannon;Hao Zhu;T. Overbye
瑞典地磁感应电流的区域 3D 建模和验证
影响因子：
3.7
作者：
L. Rosenqvist;J. O. Hall
通讯作者：
J. O. Hall
DOI：
10.1002/2017sw001697
发表时间：
2017-10
期刊：
Space Weather
影响因子：
--
作者：
T. Divett;M. Ingham;C. Beggan;G. Richardson;C. Rodger;A. Thomson;M. Dalzell
通讯作者：
T. Divett;M. Ingham;C. Beggan;G. Richardson;C. Rodger;A. Thomson;M. Dalzell
DOI：
--
发表时间：
2012
期刊：
影响因子：
--
作者：
J. Torta;L. Serrano;J. Regué;A. Sanchez;Elionor Roldán
通讯作者：
Elionor Roldán