A scalable power-line-signaling-based scheme for islanding detection of distributed generators

Power-line-signaling-based schemes are regarded as promising solutions to the problem of anti-islanding protection of distributed generators (DGs). These schemes broadcast dedicated signals from the distribution substation to the downstream DGs and, therefore, transform the detection of islanded DGs into the determination of the signal presence at the DG sites. This paper presents an improvement to a published power-line-signaling method. With this improvement, the signaling device can be located anywhere between the substation and the DG sites, creating the opportunity for designing customized anti-islanding arrangements for various DG interconnection scenarios. Simulations and laboratory tests show that the improved scheme can work reliably.