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Summary According to IEEE std. 1547, islanding mode is “a condition in which a portion of an Electric Power System (EPS) is energized solely by one or more local EPSs through the associated Point of Common Coupling (PCC) while that portion is electrically separated from the rest of the area EPS”. Therefore, the dynamic instability due to islanding may result in power swing and finally loss of synchronism. Hence, many studies have been done for islanding detection and disconnection of distributed generation (DG) in an EPS. But, these conventional methods eventually lead to the disconnection of the DG units. To improve DG dynamic stability, superconducting magnetic energy storage (SMES) can be used effectively, because SMES have a high‐energy density and fast response. This paper proposes a new method to damp the power swing after DG islanding and to maintain synchronism conditions based on SMES. Hence, the disconnection of the DG units is not required. Also, new controllers are developed for SMES including voltage source converter (VSC), and DC‐DC chopper. The controller structures of VSC and DC‐DC chopper are of PI and fuzzy logic‐based type, respectively. Superconducting coil charging is controlled by the DC‐DC chopper. SMES sizing is performed, based on power swing equations. Hereupon, dynamic load model is considered. Performance of the proposed method is evaluated by defining 12 scenarios such as strong and weak networks with load changing simulated in PSCAD. Simulation results show that the islanded DG stabilization (IDGS) method has good performance to maintain stability margin in a weak network.

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SummaryThis paper proposes a single‐ended primary‐inductor converter (SEPIC)‐based DC‐DC converter with higher voltage gain, continuous input current, and lower voltage stress. Suggested converter uses three‐winding coupled inductors and voltage multiplier for boosting function. The proposed structure stores lower amount of energy due to lower current magnitudes of used inductors. Moreover, using voltage multiplier reduces the voltage stress of the elements connected to the output terminals of the proposed converter. By reducing the voltage stress, in addition to reducing the rating of output elements and costs, the overall efficiency will also be increased. Also, a clamping circuit is used to diminish the voltage stresses on power switch. In order to represent the advantages of the proposed converter over some other converters in the viewpoints of the number of the used elements, continuity of input current, voltage gain, the voltage stress on power switch, and output diode, a comparison study is provided. To validate the practicability of the proposed converter, a 200‐W prototype is implemented and the experimental results are provided.