 |
Center for Nonlinear Studies |
During geomagnetic disturbances (GMDs), the variations in electrojet can drive geomagnetically induced currents (GIC) along transmission lines and through transformer windings to ground. The quasi-DC GIC flow in transformer windings can cause half-cycle saturations of transformer cores, resulting in increased transformer hotspot heating, accelerated aging of the cellulosic insulation and gas generation. This can dramatically impact the reliability of Bulk-Power Systems. In this work, we propose an optimization model for the transmission grid considering GIC produced by different levels of GMD events. The problem is formulated as an AC optimal transmission switching problem (AC-OTS) during GMD, in which the DC current induced by the GMD event is decoupled from the AC optimal power flow. Furthermore, we generalize our model to account for multiple GMD events as a two-stage stochastic program by using different directions and intensities. We present preliminary computational results and demonstrate the significance of the direction of GMD event on the IEEE-96 test case.
Host: Jeffrey D. Hyman/ Russell Bent