from the deterministic power flow in these lines considering data presented in [ 12 ]). Table VII shows the CLs and BBs obtained for a number of operating scenarios. Based on the results shown in Table VII for the 16 differ- ent operating scenarios, the minimum number of CLs required to realize all scenarios results from taking the union of all
This article has been accepted for inclusion in a future issue of this journal. Content is final as presented, with the exception of pagination. NASSAR AND SALAMA: ADAPTIVE SELF-ADEQUATE MICROGRIDS USING DYNAMIC BOUNDARIES 7 TABLE VI DG S R ATINGS , T YPES , AND L OCATIONS TABLE VII B OUNDARY L INES FOR A V ARIETY OF O PERATING S CENARIOS TABLE VIII CL S AND BB S FOR A LL S CENARIOS CLs obtained. The union of these CLs and the BBs obtained for all scenarios are shown in Table VIII . These CLs and BBs then determine the building clusters available as shown in Fig. 9 . However, these borders are factious and will be utilized dur- ing emergencies. In case of emergency, the system will be divided to the islands determined by the factious boundaries nevertheless during normal operations the system is intercon- nected. Hence, these factious boundaries are changed during normal operation (system is interconnected) based on the operating scenario and will be used during emergencies. According to the CLs and BBs obtained, as presented in Fig. 9 , there are 14 CLs that create 15 building clusters (step 5). These building clusters and their virtual borders are shown in Fig. 9 . The number of agents that must be allocated Fig. 9. PG&E 69-bus system with CLs and BBs. Fig. 10. Allocated agents and building cluster boundaries. is 15 (A1–A15), as shown in Fig. 8 (step 6). The locations for the isolation switches are also determined based on the CLs selected. The activation and deactivation of the agents during the operation stage then form the self-adequate micro- grids; this feature preserves self-adequacy during a variety of operating conditions. Adaptive self-adequate microgrids are produced by merging the building clusters. The size of the microgrids therefore can- not be changed by a node step because the step size is limited by the building clusters available (Fig. 10 ). However, to pro- vide the ultimate degree of freedom and a minimum step size, an agent and an isolation switch should be allocated for each node. This design is unacceptable in practical applications. For this reason, the work presented in this paper establishes a framework for allocating a reasonable number of isolation switches and agents to represent the system with a limited degree of freedom that is determined based on the number of building clusters. The system under study has 16 operating scenarios (Table V ). For each scenario, the status of the agents (A1–A15) determines the borders of the microgrids. The sta- tus for each agent is set so that self-adequate microgrids are formed for that scenario. However, the agents allocated pro- vide the operator with the ability to maneuver by overriding the
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