Hydro unit commitment in hydro-thermal optimization
- Pacific Gas and Electric Co., San Francisco, CA (United States)
In this paper the authors develop a model and technique for solving the combined hydro and thermal unit commitment problem, taking into full account the hydro unit dynamic constraints in achieving overall economy of power system operation. The combined hydrothermal unit commitment problem is solved by a decomposition and coordination approach. Thermal unit commitment is solved using a conventional Lagrangian relaxation technique. The hydro system is divided into watersheds, which are further broken down into reservoirs. The watersheds are optimized by Network Flow Programming (NFP). Priority-list-based Dynamic Programming is used to solve the Hydro Unit Commitment (HUC) problem at the reservoir level. A successive approximation method is used for updating the marginal water values (Lagrange multipliers) to improve the hydro unit commitment convergence, due to the large size and multiple couplings of water conservation constraints. The integration of the hydro unit commitment into the existing Hydro-Thermal Optimization (HTO) package greatly improves the quality of its solution in the PG and E power system.
- OSTI ID:
- 492144
- Journal Information:
- IEEE Transactions on Power Systems, Journal Name: IEEE Transactions on Power Systems Journal Issue: 2 Vol. 12; ISSN 0885-8950; ISSN ITPSEG
- Country of Publication:
- United States
- Language:
- English
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