A coordinated optimization method for system-wide power supply-demand balancing

Large-scale interconnection of power systems has provided the possibility of a wide-range better allocation of energy resources. This paper proposes a novel state-province coordinated pattern, model and method for power supply-demand balancing over the whole system. Balancing decision-making is performed based on historical contribution of provincial grids to stimulate power exchanges. Two power supply-demand balancing schemes are proposed, to minimize generation costs if power demand can be met, or otherwise, to achieve temporal and spatial equilibrium when facing power shortage. By taking the equivalent generation cost curves of provincial grids as the key optimizing information, coordinated optimization models are developed to optimize power exchange schedule between provincial grids and generation schedule of units, resulting in better allocation of energy resources. An algorithm is proposed to precisely take into account the extra cost due to limited energy output from thermal units. Computational results of 3-area IEEE RTS96 system and a large-scale real power system are presented to verify the effectiveness of the method. ©2015 State Grid Electric Power Research Institute Press