An Efficient Hybrid Islanding Detection Method for Microgrids Using Kalman Filter

ABSTRACT Islanding condition gives rise to several problems in distributed generation networks, including power quality disturbances, equipment damage, interference with grid protection, and danger to the utility crews. During islanding condition, the distributed generator (DG) operates without its referenced utility source, which is connected to the DG at the point of common coupling (PCC). Anti‐islanding protection rapidly detects the islanding scenario, and the circuit breaker at the PCC is immediately tripped to de‐energize the DG. This paper proposes an efficient hybrid islanding detection method based on harmonic content estimation of the DG unit voltage and current using Kalman filter (passive section) and fault current monitoring (active section). The main task of loss of main (LOM) protection is assigned to the passive section because it is simple, fast, and does not affect the power quality. To avoid islanding detection failure of the passive section in case of a close matching between islanded generation units and loads, the active method is employed as a supplementary part. The performance of the proposed method is assessed on a microgrid using the IEEE benchmark system. Simulation with different conditions proves the validity of high speed and correct results in applying the proposed method.