Stochastic optimization for hydro‐thermal power systems

Abstract

SUMMARYA suboptimal stochastic optimization method for the long-term scheduling of a hydroelectric reservoir is described. The objective of the optimization is to minimize thermal station fuel costs, in a mixed hydrothermal power system, over a one-year horizon. Exact stochastic and deterministic solutions, obtained by dynamic programming (DP) for a simple one-reservoir model, are compared. The two solutions differ significantly, indicating that deterministic solutions to the problem are inadequate. Stochastic DP is not computationally feasible for a multi-reservoir system. A suboptimal linear feedback controller with nonGaussian reservoir water storages is then developed. It approximates the stochastic DP solution for one reservoir very well and is capable of extension to a multi-reservoir version.