Simulation of the Effects of the 13-14 March 1989 Severe Geomagnetic Storm on Today’s Electrical Power Grid using Contemporary Geoelectric Field Estimation Techniques

Abstract:

The severe geomagnetic storm of 13-14 March 1989 had well documented and significant impacts on the electrical power infrastructure over North America. Since that time, the power grid has continued to grow in complexity and interdependence; likewise the understanding and modeling of processes that physically link space weather disturbances to the induction of current in power systems has progressed significantly. We investigate the effects this storm would be expected to have on today’s power grid by running a simulation of the storm using an up-to-date approach for estimating the natural geoelectric field induced at the surface of the Earth during the event. Specifically, we take magnetic field time series from a network of 19 observatories in the U.S. and Canada, model the magnetic field variations on a regular ½ degree geographical grid using those inputs, and convolve the modeled magnetic field with electromagnetic transfer functions at locations where recent magneto-telluric survey data are available. The modeled geoelectric fields are interpolated to power line locations and integrated along the lines to determine induced voltages on each line. The induced currents are then derived using PSS®E simulation software which accounts for the relevant system parameters such as system geometry, connectivity, line resistances and grounding resistances. We examine and discuss details of the PSS®E simulation outputs to estimate how today’s power grid would respond to the occurrence of a geomagnetic storm similar in magnitude to the 13-14 March 1989 event. The sensitivity of these results to variations of the geoelectric modeling methodology will also be briefly considered.