Islanding detection method for PV grid-connected inverter based on dynamic reactive power disturbance

Island detection is the essential function of the distributed grid-connected power generation systems, and it is also the difficulty of the research. Active detection method such as frequency shift or sliding mode frequency disturbance, injecting harmonics to the grid, which influences the grid power quality, and there is a certain non-detection zone (NDZ). Therewith, a kind of island detection method based on reactive power disturbance has been put forward in this paper. Simulation and experimental results show that the reactive power of the disturbance of island detection method not only achieve detection with no non-detection zone, small harmonic content of output waveform, and closing a tiny change of reactive power, but also because the disturbances have little effect on the output power of photovoltaic power generation system.