Islanding detection method based on a new approach to voltage phase angle of constant power inverters

Abstract

This study presents a new islanding detection approach using the notion of active methods. A difference between the instantaneous and nominal voltage phase angle (VPA) of a distributed generation (DG) is applied to inverter-based interface control. After the islanding phenomenon, currents id and iq will be changed by adding the variation of the point of common coupling VPA to input of d–q transformation block of currents. This subsequently causes the voltage and frequency deviations using for detecting island. Active islanding detection techniques usually leave adverse effects on power quality. The considerable advantages of the proposed method include insignificant negative effects on the power quality in the normal operation of the power system. The performance of the proposed islanding detection method is evaluated by some common test presented in UL1741; in addition, the results of some tests are presented for multiple DGs that show the proposed method does not cause significant interference between two DGs in the operational mode. Analogous to the case of a single DG, the island was also detected well in the case of multiple DGs.