Scheduling Post-Disaster Repairs in Electricity Distribution Networks

Abstract

Natural disasters, such as hurricanes, large wind and ice storms, typically require the repair of a large number of components in electricity distribution networks. Since power cannot be restored before the completion of repairs, optimal scheduling of available repair crews to minimize the aggregate duration of customer interruptions reduces the harm done to the affected community. While incorporating a switch on every line of a distribution network would maximize the outage management capability and resilience, cost concerns typically prohibit such an approach. In this work, we consider the fact that the number of switches is much smaller than the number of edges in the distribution network. This generalizes the problem adopted in our previous work [1]. Our modeling framework is analogous to a job scheduling problem with group soft precedence constraints on parallel identical machines to minimize the total weighted energization time. We propose a linear programming (LP) based list scheduling algorithm and a conversion algorithm and analyze their theoretical performances.

Distribution Systems Hardening Against Natural Disasters

“…In this section, we briefly review the problem of sequencing post-disaster repairs in distribution networks with a single repair crew. Further details, including scheduling with multiple repair crews, can be found in [33].…”

“…The set of edges in G ′ is the set of damaged edges in G, L D . The second graph, P , called a 'soft precedence constraint graph', is formally defined in [33]. An edge exists between two nodes in P if they share the same node in G ′ .…”

“…We begin with the following lemma, which states that sequencing post-disaster repairs in distribution networks with a single repair crew is equivalent to the scheduling problem 1 | outtree | n∈N w n C n , for which an optimal algorithm exists [2]. A proof of this lemma can be found in [33].…”

“…Physical damage to grid components must be repaired before power can be restored [20,34]. On the operational side, approaches have been proposed for scheduling the available repair crews in order to minimize the cumulative duration of customer interruption, which reduces the harm done to the affected community [7,22,33]. On the planning side, Kwasinski et al [16] reported that facilities that had been upgraded or hardened in Christchurch at a cost of $5 million, remained serviceable immediately after the September 2010 earthquake and saved approximately $30 to $50 million in subsequent repairs.…”

DER Allocation and Line Repair Scheduling for Storm-induced Failures in Distribution Networks

“…A key aspect of our formulation is that we allow for the partial DN operation in situations when the bulk power supply is no longer available, and it is beneficial to operationalize microgrids during the recovery period. Literature is now available on the allocation of repair crew and optimal response operations [8]- [11]. These contributions focus on resource limitations, failure uncertainties, and physical constraints.…”