Islanding behaviour of grid-connected PV inverters operating under different control schemes

This paper compares the islanding behaviour of different inverter implementations, which have current source or voltage source characteristics. Measurements were made on a number of commercially available inverters, and simulation models were developed to enable further investigation of the influence of the type of control system on islanding operation. Additionally, a modified active-frequency-drift detection method is presented which reduces the amount of distortion introduced to the grid compared with the conventional approach often described in the literature.