Mitigation of snowstorm risks on power transmission systems based on optimal generation re-dispatch

A multi-step methodology is proposed in this paper to help prevent ice accretion on the power transmission lines exposed to severe ice and snowstorms. The goal is to use the heat gain due to resistive losses in the line to prevent ice from being formed. The proposed algorithm first attempts to re-dispatch the power generation units in such a way that it increases the flow of power through the at-risk lines. If this is not sufficient in preventing ice accretion, in the next step, an area-based forced outage scenario is determined through which one or more lines are intentionally de-energized in order to further increase the power flows through the at-risk lines. If none of the previous steps manage to bring these lines back into safety, a stochastic contingency constrained generation dispatch model is formulated as a last resort so as to maintain the continuity of supply to the loads subject to possible failure of one or more at-risk lines due to severe ice accretion. The IEEE 118-bus power system has been used as a case study to provide numerical results and evaluate the efficiency of the proposed methodology.