Islanding detection of grid connected distributed generation using symmetrical components

Network fluctuations occurring at different situations impact the accuracy of islanding detection method. An islanding detection method based on the theory of symmetrical components is proposed. A single variable threshold limit for islanding detection may lead to incorrect results and a new mathematical formula with more than one variable is proposed. Simulation studies with the proposed method for various operating conditions, such as connecting and disconnecting different types of loads, tripping of other DG and applying both symmetric and asymmetric faults at different location on the distribution system, verify that the proposed method correctly detects the islanding operation and does not mal-operate.