Networked Microgrid Scheduling for Resilient Operation

The rapid development and wide acceptance of microgrids call for new methodologies to comprehensively model all the active components within microgrids and specifically focus on islanding requirements when the main grid power is not available. To ensure a high level of reliability of the interconnected microgrid (MG) network, an optimal scheduling model is proposed that minimizes the day-ahead cost of the MGs, while considering existing operational constraints. The original problem is decomposed into two main operating conditions, namely, grid-connected and resilient operations. The objective is to ensure a sufficient online capacity for all the MGs in the network in the case of an emergency islanding situation, such as during an extreme weather event. The exact time and duration of these events are generally unknown, thereby resulting in having to consider a number of possible islanding scenarios for each event. In this paper, optimal scheduling is determined to ensure feasible islanding for all the probable scenarios of the event, preserving load shedding as the last resort. The optimization model has been implemented on different layouts of the modified IEEE 123-bus test system for different events during a period of 24 hours. Besides proposing resiliency-oriented day-ahead scheduling for multiple MGs, cost analysis and comparison among all the test cases are also presented. The results obtained prove the proposed day-ahead scheduling algorithm to be beneficial for the MG owners, especially when networking with neighboring MGs.