A clipping-off interior-point technique for medium-term hydro-thermal coordination

This paper presents a clipping-off interior-point algorithm for hydro-thermal coordination which allocates hydro and thermal resources in order to minimize the cost. The clipping-off algorithm basically consists of setting the control variables to their upper or lower bounds if certain conditions are met, and eliminating them as variables from the problem formulation thereafter. The number of FLOPS and iterations to obtain the problem solution is considerably reduced as compared to a standard interior-point solution; however, the solution obtained by either method is the same. Based on the hydro-thermal power system of Spain, computational examples are presented; these examples are used to compare the proposed clipping-off predictor-corrector log-barrier algorithm with the standard predictor-corrector and the standard log-barrier algorithms.