Study on Relationship between Power Grid GIC (Geomagnetically Induced Currents) and Interplanetary Disturbances

Abstract

Geomagnetically induced currents (GIC) are very harmful to the power system and caused by the changes of geomagnetic field. The changing magnetic fields originate from the interplanetary space. Therefore, recognizing the relationship between GIC and interplanetary disturbances is significant for the prediction of GIC. In this paper, we collected 35 GIC events during 1999-2005 and the corresponding interplanetary data observed by ACE satellite to analyze the correlations of various interplanetary parameters with GIC. The results show that there is positive correlation between GIC amplitudes and interplanetary parameters. As a single factor, solar wind dynamic pressure (Pk) correlates best with GIC, while interplanetary electric field (Ey) and interplanetary magnetic field (|B|) also correlate well with GIC. In addition, we investigated the relationships between interplanetary parameters and GIC amplitudes for different intensities (GIC>10A, GIC>20A). Comprehensive analysis shows that Pk and Ey are the most closely parameters related to GIC.