Optimal Transmission Line Switching under Geomagnetic Disturbances
Abstract
In recent years, there have been increasing concerns about how geomagnetic disturbances (GMDs) impact electrical power systems. Geomagnetically-induced currents (GICs) can saturate transformers, induce hot spot heating and increase reactive power losses. These effects can potentially cause catastrophic damage to transformers and severely impact the ability of a power system to deliver power. To address this problem, we develop a model of GIC impacts to power systems that includes 1) GIC thermal capacity of transformers as a function of normal Alternating Current (AC) and 2) reactive power losses as a function of GIC. We use this model to derive an optimization problem that protects power systems from GIC impacts through line switching, generator redispatch, and load shedding. We employ state-of-the-art convex relaxations of AC power flow equations to lower bound the objective. We demonstrate the approach on a modified RTS96 system and the UIUC 150-bus system and show that line switching is an effective means to mitigate GIC impacts. We also provide a sensitivity analysis of optimal switching decisions with respect to GMD direction.
Keywords
Cite
@article{arxiv.1701.01469,
title = {Optimal Transmission Line Switching under Geomagnetic Disturbances},
author = {Mowen Lu and Harsha Nagarajan and Emre Yamangil and Russell Bent and Scott Backhaus and Arthur Barnes},
journal= {arXiv preprint arXiv:1701.01469},
year = {2017}
}