A systematic gain setting method of the positive feedback anti-islanding scheme for inverter-based distributed generators

This paper proposes a systematic gain setting method for the positive feedback anti-islanding scheme which is designed to protect the interconnected inverter-based distributed generators (DGs) from islanding operation. Two main factors affecting the performance of the anti-islanding scheme are investigated when the positive feedback gain is tuned. One is the stability impact of the anti-islanding control on distributed generation (DG) systems and the other is the islanding detection time of the anti-islanding scheme. The small-signal model and the electromagnetic transient simulation model of an inverter-based DG system are developed to facilitate the realization of the proposed gain setting method. This method provides a practical and reliable tool for DG planning engineers.