Ramp‐based scheduling vs. energy‐block scheduling in day‐ahead market (DAM)

Abstract

It has been recently reported that conventional unit commitment approach, which is based on energy-block, may not be capable of guaranteeing that the resulting energy schedule is feasible for dispatch [1, 2, 33, 41, 65-67]. Moreover, due to some underlying accepted assumptions widely used in Unit Commitment (UC) formulations, inefficient deployment of resources and ramp constraint violations could take place, with resulting increases in system operational costs; furthermore, security of the entire power system could even be jeopardized. Thus, this thesis has applied a newly proposed UC formulation proposed by Germán in [1, 2], which draws a clear distinction between power and energy, trying to identify the benefits of using power-based UC scheduling, instead of energy-blocks scheduled on an hourly basis. Piecewise-linear power trajectories are used for modeling both demand and generation. Moreover, startup and shutdown power trajectories are also taken into account, to obtain more efficient scheduling. A realistic system ― ERCOT is used as a case study to conduct experiments. Between power-based UC scheduling and traditional UC formulation, lots of comparisons are made in the thesis. A brief introduction and literature review about unit commitment and short term planning is given at the beginning of this thesis. The differences between the two UC formulations are presented afterwards. Finally, numerical results and tables, along with discussions and comparisons are shown at the end, giving conclusions as evidential support.