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Summary Renewable sources of energy are used extensively in the distribution grid to meet the need for growing electricity demand and to resolve the global heating crisis caused by traditional energy sources. They offer many advantages like better efficiency, power quality, and lower air pollution. One of the vital issues with these integrations is islanding condition arising due to the sudden disconnection of grid because of some abnormal situations; however, the distributed generation (DG) retains the power supply to the local loads. Thus, efficient detection of islanding and quick detachment of DG are vital to prevent failure of equipments, grid safety disruption, and risks to personnel safety. In this context, this article represents a comprehensive review of islanding issues and different islanding detection methods (IDMs) that provide a detailed assessment for filling the research gap and thereby highlights the various issues related to island detection. A broad classification of IDMs is established based on the conventional and modern techniques such as local (Active, Passive & Hybrid) and remote IDMs with their detailed illustrations including both intelligent and signal processing‐based IDMs. Comparison of various IDMs based on their merits, demerits, and various performance analysis including the non‐detection zone, detection time, quality factor, power quality, effect on a microgrid, implementation cost, and applicability in multi‐DG system is provided. Hence, this review will provide an insight for the new researchers interested in the area highlighting the different islanding detection techniques with their relative merits and demerits.

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A novel soft-switched inverter topology in which three mutually coupled inductors at a time are involved in the resonance process is proposed. By the introduction of magnetic coupling between three resonant inductors, the zero-voltage instants for the inverter can be generated by one auxiliary switch. Also, the resonant energy can be recycled, and the maximum voltage stress on the auxiliary circuit diode components is confined to the DC-link clamp voltage level. The DC link can be clamped to 1.1-1.3 times the DC-source value. This is unlike the soft-switched inverter in which two mutually coupled inductors are at a time are involved in a resonance process [14], wherein the clamping diode experiences voltage stress of the order of 11 per unit when clamping the DC-link voltage at 1.1 per unit. The proposed inverter also provides pulse-width modulated operation. An analysis of this novel quasi-resonant DC-link inverter topology is presented to reveal its softswitching characteristics. Simulation and laboratory experiments are performed to validate the analysis.