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This article presents a new algorithm for fault detection in grid-tied microgrids with inverter-interfaced distributed generators (DGs). To support the Grid codes, the DGs require a low voltage ride through (LVRT) capability. The control strategy used in the DGs results in large changes in the fault characteristics of the microgrid. Hence, it is required to study the fault characteristics of the DGs in a microgrid under various operating conditions. The study presents fault detection for microgrids with PQ-controlled DGs having LVRT capability under different DG voltage and different fault conditions (high impedance and low impedance). The fault location has been identified using the phase change in the positive sequence current at specific DG voltages. The reliability of the proposed scheme has been validated under diverse fault conditions through extensive simulations in the Matlab/ Simulink environment, and the comparison with other fault detection techniques proves the efficacy of the proposed scheme for fault detection in microgrids. [ABSTRACT FROM AUTHOR]

• An efficient multi-objective algorithm has been proposed for optimized operation of DGs to reduce voltage unbalance at different buses. • The voltage unbalance limits for different buses can be customized according to the distinctive requirement of the consumers. • The negative sequence voltage has been reduced as much as possible. • The positive sequence voltage has been increased by incorporating LVRT capability in the DG control. • The DG output current is also optimised since the power interfacing converter consists of semiconductor devices which cannot withstand excessive currents. • Several case studies have been conducted and the performance of the proposed method has been tested in real time digital simulator. Voltage unbalance control plays an important role in maintaining the power quality standard in microgrid. This paper presents a multi-objective control strategy to realize optimal voltage unbalance compensation in a multibus microgrid, satisfying customized power quality requirement of the consumers at different buses. The distributed generators (DGs) in the microgrid share the compensation effort cooperatively to satisfy the power quality standard at different buses. Multi-objective Artificial Cooperative Search Algorithm (MOACS) has been proposed to solve the multi-objective pareto optimization problem. The algorithm assigns compensation reference to all the DGs so that the DGs can accordingly compensate the negative sequence voltage at different buses and thereby mitigate voltage unbalance. The effectiveness of the proposed scheme has been established through the results obtained from simulation and real time digital simulator. [ABSTRACT FROM AUTHOR]