When to island in the controlled islanding scheme to prevent imminent wide-area blackouts

In recent decades, blackouts spread around the world due to an increasing penetration of Distribution Generation (DG) and commercial benefits with maximizing utilization of transmission and distribution networks. Normally, blackouts are imminent when usual methods in the widely-used three-defence-line scheme fail, such as preventive control, emergency control and corrective control. An adaptive and controlled islanding scheme has already been proposed to be undertaken as a last-resort action to prevent imminent wide-area blackouts. In this paper, we present this controlled adaptive islanding scheme and investigate one crucial question “when to island”, which decides if the controlled islanding scheme could be successful. Finally, in order to create cascading failure scenarios in complicated power systems during dynamic simulation, which is the main nature of blackout, modeling of protection system for networks and generators are proposed to develop.