Application of Synthetic Geomagnetic Storms on Transformer Thermal Assessment

The lack of extensive data on severe geomagnetic storms has necessitated the need to generate synthetic time-series electric field, particularly to assess and predict the im-pact of such extreme storms on the resilience of the electric power grid. Due to geomagnetic disturbances, geomagnetically induced currents (GIC) can lead to half-cycle saturation of the transformers, placing the equipment at the potential risk of experiencing increased hotspot heating. This paper describes a methodology for generating extreme synthetic geomagnetic storms through an iterative process of temporally and spatially varying the fragments of the NERC benchmark event by scaling the time duration, magnitude, and direction of the storm. In addition, the results of the thermal sensitivity of the transformers to the assumed quasi-de electric fields simulated on a large-scale synthetic electric grid are presented. Further engineering assessments may utilize the computed extreme GIC scenarios.