An effort to develop a unit commitment approach capable of handling large power systems consisting of both thermal and hydro generating units offers a large profitable return. In order to be feasible, the method to be developed must be flexible, efficient and reliable. In this paper, various proposed methods have been described along with their strengths and weaknesses. As all of these methods ...

In the single objective Unit Commitment Problem (UCP) the problem is usually separated in two sub-problems : the commitment problem which aims to fix the on/off scheduling of each unit and the dispatching problem which goal is to schedule the production of each turned on unit. The dispatching problem is a continuous convex problem that can easily be solved exactly. For the first sub-problem gen...

This paper proposes a novel technique for solving generation scheduling and ramp rate constrained unit commitment. A modified objective function associated with a new start-up cost term is introduced in this paper. The proposed method is used to solve generating scheduling problem satisfying SRR, minimum up and down time as well as ramp rate constraints. Two case studies are conducted to imp...

Everyday, electricity generation companies submit a generation schedule to the grid operator for the coming day; computing an optimal schedule is called the unit-commitment problem. Generation companies can also occasionally submit changes to the schedule, that can be seen as intra-daily incomplete recourse actions. In this paper, we propose a two-stage formulation of unit-commitment, wherein b...

We develop a two-stage stochastic programming model with integer first-stage and mixed-integer recourse for solving the unit commitment problem in power generation in the presence of uncertainty of load profiles. The solution methodology rests on a novel scenario decomposition method for stochastic integer programming. This method combines Lagrangian relaxation of non-anticipativity constraints...

An efficient Unit Commitment (UC) plays an important role in the economic operation of a power system. The generation planning mainly concerns with the short-term generation scheduling, i.e. unit commitment, which determines the optimal set of generating units to be used over a time horizon of a day or a week. The UC problem has commonly been formulated as a nonlinear, large-scale, mixed-intege...

The unit commitment problem is to find the production scheduling of a set of electric power generating units, and the generation levels for each unit, over a short term, typically from 24 hours to one week. The objective is to find the optimal schedule which meets the energy demand forecast at a minimum cost, and satisfy technological constraints such as the minimum up and down times for the un...

This paper solves reliability constrained unit commitment problem (UCP) for a composite power system network using network equivalent technique. Here, the integration of generation and transmission system reliability forms a composite power system model. The inclusion of load forecast uncertainty for the solution of unit commitment problem will give more accurate assessment of spinning reserve ...