Coronal mass ejections ( CMEs ) are vast eruptions exploded from the solar atmosphere, which can affect the life of our human being. The geomagnetically induced current which is driven by coronal mass ejection can damage the power transmission system, especially for an extra-long distance electric power transmission system. We have analyzed the coronal mass ejection (CME) data from SOHO / LASCO, the geomagnetically induced current data and the geomagnetic storm data, which are from the North China Electric Power University and the Finnish Meteorological Institute.We have studied the characteristics and physical properties of all halo coronal mass ejection, which are related to geomagnetically induced currents. This thesis is structured as follow: In chapter one, coronal mass ejections, geomagnetically induced currents, magnetic storm, prediction method for solar activity and wavelet transform are introduced. In chapter two, the relationship between geomagnetically induced currents and coronal mass ejections, magnetic storm, geomagnetic field variation have been analyzed. According to their symmetry, the observed halo CMEs are classified into three types: complete symmetry, brightness asymmetry, and outline asymmetry We found that the brightness asymmetric halo CMEs have the maximum possibilities to cause the major damage to the transmission system. The geomagnetically induced current also has a good correlation to the time variation of the geomagnetic field dB/dt. The geomagnetically induced current events that are driven by three different types of halo coronal mass ejection have different characteristics in intensity, duration and period. In chapter three, the conclusion and prospect are presented.
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