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Due to the increase of load demand, the utility tends to utilize DG technology in recent years. The intentional islanding is an appropriate approach to enhance system performance such as reliability and operational flexibility. This research provides a new paradigm for intentional islanding to maximize the efficiency of the power system. The methodology is based on an advanced load shedding algorithm to achieve a load generation balance and control strategy to ensure a smooth transition from normal mode to island mode with high load power quality. Moreover, it is suggested to assess the small-signal stability of new islands to evaluate their performance and give priority among different alternatives. IEEE 33-bus system is taken as a case study to ensure the effectiveness of the introduced methodology. The analysis is performed for a case study with optimal DG locations and sizes. NEPLAN software is used for dynamics and small-signal stability investigations. [ABSTRACT FROM AUTHOR]

• Main features of fault response in DC microgrids are discussed. • The characteristics and settings of the proposed Smart Power-Voltage Relay are presented. • Different case studies are investigated to validate the effectiveness of the proposed relay. Microgrids are considered a prospective way towards improving electric service resiliency, reducing costs, and upgrading service reliability. DC microgrids offer many advantages rather than AC microgrids. In spite of the numerous features and advantages of DC microgrids, their protection faces significant challenges such as self-limited current of photovoltaic (PV) systems, long time constant of wind energy systems, dependability on communication systems, etc. The paper introduces a new protection scheme for DC microgrids using the rate of power (dP) and rate of voltage (dV) and mapping them as dP-dV profile. The new scheme is titled as smart power/voltage relay (SPV-Relay). The proposed scheme is applicable for all types of renewable energy sources (RESs) and energy storage systems independent of the power rating and configuration of the DC microgrid. The proposed concept of SPV-Relay is described and the method used for fault discrimination is explained. The relay characteristics are developed considering all the DC microgrid components. Three operating zones are identified on dP-dV profile to discriminate between various fault types and locations. The sensitivity and stability of the proposed relay are evaluated under different fault conditions as well as different control schemes and operational scenarios for DC microgrid. [ABSTRACT FROM AUTHOR]