Impedance Estimation and the Total Harmonic Distortion Methods for Islanding Detection

An islanding situation should be detected accurately soon after the island is formed. Because failure to trip the islanded distributed resource can lead to a number of problems for the resource and the connected load. Therefore, it is important to distinguish islanding and non-islanding situations and block the nuisance tripping effectively. This paper compares two islanding detection methods, during the load variation (non-islanding) and power imbalance closely match (islanding) conditions, the performance of these two methods are investigated.