GAMS Environment Based Solution Methodologies for Ramp Rate Constrained Profit Based Unit Commitment Problem

The convergence of the electric power industry toward the competitive framework throughout the world has led to a market environment replacing the traditional monopolistic scenario. It has given rise to more efficient production and distribution of electricity, provided a better choice to market participants while maintaining the security and reliability of the power supply. Earlier power utilities had been producing electrical power with the objective to minimize the costs and demand, as well as reserves, were met. Under the new structure, generation companies (GENCOs) schedule their generators to maximize profit. This paper uses a new approach to deal with profit-based unit commitment (PBUC), considering the conditions of power and reserve. The proposed method allows GENCO to decide how much power and reserve should be sold in the markets to achieve maximum profit. For the PBUC problem, three computational techniques, namely ANTIGONE, COUENNE, and BARON in general algebraic modeling system (GAMS), have been applied on three test case studies comprising three, ten, and hundred thermal units in a day-ahead power market. The uncertainty in the energy spot price has been considered using Monte Carlo simulation approach. The various diversified constraints such as system energy load, spinning reserve, ramp rate, unit up and downtime imposed on the PBUC problem have been considered while solving the problem. Simulation results demonstrate that the BARON method has provided better results and has outperformed over the ANTIGONE and COUENNE methods and previously existing techniques reported in the literature in terms of solution quality, the satisfaction of constraints, and an ability to solve large-scale test system.