Coordinative Optimization Model Based on MILP for Hydrothermal Power System

This paper develops a model for scheduling large-scale hydrothermal power systems based on the Mixed Integer linear Programming (MILP) technique. The advantage of this model is that the schedules can make coordinated decision for hydro and thermal units, take into full account the hydro unit constraints in achieving overall economy of power system operation. The planning problem is not decomposed into sub-problems for hydro and thermal units, instead hydro and thermal units are scheduled to find solution of global optimization. This paper concentrates on the solution methodology for hydro problem with electric quantity constraints and discrete hydro constraints, and coordinative optimization model of hydrothermal power systems on the basis of Security Constrained Unit Commitment (SCUC) and Security Constrained Economic Dispatch (SCED) are discussed in the paper. The model is illustrated by example of a provincial network power system. Numerical result based on this practical system show that this method is efficient and effective for dealing with hydrothermal systems.