Identification and visualisation of circular flows in a superior cluster‐graph display for operational control.

Large interconnected power grids like the European transmission system tend to increase their power interchange as a result of the liberalisation of the electricity market as well as the increasing integration of intermittent power resources such as wind farms and photovoltaic. As a consequence of this, undesired circular power flows (loop flows) may occur, which means circulating active power between the control‐areas of several transmission system operators (TSOs). A superior survey of the occurrence of such phenomena in the context of operational control seems to be very useful, because uncontrolled power exchange reduces the transfer capabilities of power corridors and may cause unnecessary and avoidable line congestions or even overloads. This study demonstrates how the depth‐first search algorithm from graph theory can be adopted together with a superior cluster display of control areas in order to identify and visualise such kind of flows and to facilitate common situation awareness for operational control in control centres of TSOs in large interconnected systems. [ABSTRACT FROM AUTHOR]