Anti-islanding protection using a twin-peak band-pass filter in interconnected PV systems, and substantiating evaluations

The authors have successfully developed and industrialized a new frequency-shift anti-islanding protection method using a twin-peak band-pass filter (BPF) for grid-interconnected photovoltaic (PV) power systems. In this method, the power conditioner has a twin-peak BPF in a current feedback loop in place of the normal BPF. This new method works perfectly for various kinds of loads such as resistance, inductive and capacitive loads connected to the PV system. Furthermore, because there are no mis-detections, the system enables the most effective generation of electric energy from solar cells. A power conditioner equipped with this protection was officially certified as suitable for grid-interconnection