Research On The Effects Of Different Intensities Geomagnetic Storms Affecting High-speed Railway Traction Network

The rapid variation in geomagnetic field caused by solar storms would induce earth surface potentials(ESP), which could disturb ground-based technological systems such as railways, power grids and pipelines in forms of geomagnetically induced currents (GIC) or ground potential. Some railway’s fault events in history, such as the serious failure occurred in signal and switching system of the New York Central Railroad, the red-light-strap failure in which some traffic lights of railways in southern Sweden, and the anomalies which are not related to technical reasons in Signalization, Centralization and Blockage (SCB) systems of Northern railway in Russia, have been proven to be caused by strong geomagnetic storms. Compared to traditional railways, the high-speed railways are not only improved significantly in speed, but also a fairly new high-tech vehicle. Thus, the more complex high-speed railway electrical systems, are more susceptible to external electromagnetic interference. Research on the effects of geomagnetic storms affect electrical systems for passenger dedicated line of high-speed railways is a major issue which related to railway transport safety. It is also a front subject on the effects of space weather on ground-based technological systems.This paper based on the mechanism analysis of geomagnetic storms affecting high-speed railway electrical systems, monitoring technique of GIC flowing in power grids and monitoring data analysis methods. Firstly, the effects mechanism of geomagnetic storms affecting traction network and track circuit is analyzed. Secondly, we utilized the GIC monitoring device installed in Hebi East traction substation of the Beijing Guangzhou High-speed Railway to collect the data during March 17th to 19th and June 22nd to 24th in 2015 when there are two strong geomagnetic storms. Then, the monitoring data and geomagnetic storm data which is collect from Shandong Province Malingshan Magnetic Observatory are performed comparative, statistical and correlational analysis. The results showed that GIC will flow in high-speed railway electrical systems. Thirdly, based on characteristic of traction network and the GIC research methods of power grids, equivalent models of traction network are set up. Finally, based on one-dimensional layered-earth conductivity model and geomagnetic storm data in March 17th, the earth surface electric field of resistive and conductive impedance model has been calculated respectively. Then, 0.2V/km,1V/km and 2V/km uniform Northward electric field and uniform Eastward electric field are selected as the hypothetical equivalent voltage source. And based on the GIC equivalent models of traction network, the geomagnetically induced current in traction network has been calculated by different equivalent voltage source The results showed that traction network of high-speed railway would produce several to tens of Ann’s GIC. So it may affect safety of high-speed railway traction power supply system.