Decision support tool for optimal dispatch of tertiary control reserves

A decision support tool helping the transmission system operator (TSO) dispatchers to minimize the costs for the load–frequency control is proposed in this paper. Dispatch of tertiary control reserves is done primarily with an aim to ensure secure operation of the transmission system, while the costs associated with utilization of the control reserves are traditionally of less importance. The mixed-integer linear programming based optimization tool proposed in this paper suggests such activation of tertiary control reserves which minimizes the costs for the control reserves utilization and ensures secure operation of the transmission system at the same time. Through a case study comparing the control based on the decision support tool with historical control performed manually by the TSO dispatchers, it is demonstrated that the costs for the load–frequency control could be reduced.