Sequence-Based Hybrid Technique for Islanding Detection for Microgrid With RES

In this work, the detection of islanding of a microgrid having different types ofRES (DGs) has been presented. It proposes a technique that uses two new developed criteria; 1) Discrimination factor of islanding (DFI) and 2) superimposed angle of positive sequence impedance (Delta phi(1Z)), for the true discrimination between islanding and non-islanding events (NIEs). The technique utilizes the developed criteria in hybridization to complement each other. The efficacy of the proposed hybrid technique has been tested on a 7-bus microgrid test system for illustration and has also been verified on a modified IEEE 34 bus system. All the simulations have been carried out in the RTDS/RSCAD environment. The proposed technique distinguishes the islanding from NIEs in the 9 ms even at the 0% power mismatch; therefore, restricts the undesirable tripping due to the various kinds of non-islanding events. The islanding has been determined considering each type of DGs as targeted distributed generator (DG) in various cases. Acomparison of the obtained results has also been performed with the existing methods to show the superiority of the proposed technique. The effects of quality factor of load, sampling frequency and noise have also been studied.