Islanding detection method for inverter-based distributed generation with negligible non-detection zone using energy of rate of change of voltage phase angle

A simple technique is proposed in this study, aimed at the islanding detection of an inverter-based distributed generation (DG). The main advantage of the proposed technique is its reliance on a simple approach for islanding detection with negligible non-detection zone and keeping the unchanged output power quality. This work attempts to detect islanding conditions through computing the rate of change of voltage phase angle (ROCOVPA) of the point of common coupling by phase-locked loop (PLL) in inverter controllers. Because almost all inverter systems are equipped with the PLL, its implementation for inverter-interfaced DGs is simple and economical. Simulation results show that the durability energy of ROCOVPA is different for islanding and non-islanding conditions. In fact, in non-islanding condition the energy of ROCOVPA reduces to a negligible value after a certain time, but in islanding conditions it has considerable variation. The proposed method is evaluated using the conditions dictated by the IEEE 1547 and UL 1741 standards. The simulation results are presented to highlight the effectiveness of the proposed technique. In addition, the proposed method is compared with several passive and intelligent methods and it is confirmed that the proposed method has better performance and more accuracy.