Optimal energy dispatch of the power distribution network during the course of a progressing wildfire

Abstract

Summary Wildfires are natural phenomena that play a crucial role in many forest and grassland ecosystems. Under favorable conditions, that is, extreme heat, availability of fuel, and high winds, they may spread beyond control and approach city limits. Power lines are vulnerable to wildfires in their vicinity, mainly because of increased conductor temperatures as a result of ambient temperature rising. This may lead to conductor annealing and/or increased sag. A violation of safety clearances of the lines could in turn lead to possible flashovers and onset of cascading failures. To address the situation, the operator may dynamically alter the ratings of the lines in the affected areas in order to reduce the flow of current through them, thereby assisting with conductor cooling. However, with reduced line capacities, the utility may not be able to supply all the loads from the main substation anymore, which may increase the risk of unserved load and load shedding. A solution is put forth in this paper that enables the system operator to dispatch distributed generators, demand responsive loads, and microgrids in order to supply loads under such emergency conditions. Because of the uncertain spread/severity of wildfires, the problem is stochastic in nature and is therefore modeled as two‐stage stochastic optimization. First‐stage variables determine the generation capacity to be purchased before the onset of the event, while second stage variables represent generation dispatch commands. The efficiency of the proposed solution is verified on a modified version of the Institute of Electrical and Electronics Engineers (IEEE) 123‐bus test system. Copyright © 2014 John Wiley & Sons, Ltd.

Optimal resilient power grid operation during the course of a progressing wildfire

“…In contrast to [11], we assume a time horizon of a single period, i.e., T ¼ 1. The reason is that the presented formulation (14)- (26) (as well as the formulation presented in [11]) decouples with the periods, t. In other words, there is no coupling of the stages.…”

“…Just like in [11], the operator can take one or more of the following actions during emergency conditions in order to reduce the total load on its network:…”

“…The goal of the proposed optimization framework in [11] is to find a dispatch of energy resources, which allows for the optimal operation of the power grid during the course of a wildfire event.…”

“…The mathematical programming model investigated is based on the two-stage stochastic optimization model proposed by Ansari and Mohagheghi [11]. The disaster is modeled as a decrease in transmission capacity (at a single line).…”

“…We use the same test system as in [11] which is a modified version of the IEEE 123-bus test distribution system [22], equipped with four Microgrids, cf. Fig.…”