Geomagnetic disturbance modeling results for the AEP system: A case study

Geomagnetic disturbances (GMDs) drive geomagnetically induced currents (GICs) into the power grid. These have the potential to cause half-cycle saturation of transformers and increase their reactive power consumption. This paper provides an illustrative assessment of GMD impacts on a bulk electric system such as the American Electric Power (AEP) East system. This is done by integrating GIC analysis into power flow studies of the system. Parts of the system likely to experience high GICs are identified, with a corresponding analysis of the impacts on system voltages. Some background on the GMD-integrated power flow modeling approach is provided.