Anti-islanding detection method using Negative Sequence Voltage

This paper presents an active Anti-Islanding Detection (AID) method using Negative Sequence Voltage (NSV) injection to electrical grid through a three-phase photovoltaic (PV) inverters. Because islanding operation mode can cause a variety of problems, the islanding detection of grid-connected PV inverter is the mandatory feature. The islanding mode is detected by measuring the magnitude of Negative Sequence Impedance (NSI) calculated by the negative sequence voltage and current at the point of common coupling (PCC). Simulation and experiment are performed to verify the effectiveness of the proposed method which can detect the islanding mode in the specified time. The test has been done in accordance with the condition on IEEE Std 929–2000.