Application of grey linear programming to short-term hydro scheduling

An approach using linear programming based on grey constrained interval is applied to solve the short-term hydro scheduling problem. A characteristic feature of this approach is that the errors in the forecast hourly loads and natural inflows can be taken into account by using grey number notation, making the approach superior to the conventional linear programming method in which the hourly loads and natural inflows are assumed to be exactly known and there are no errors in the forecast loads and natural inflows. To reach an optimal scheduling under the uncertain environment, a grey linear programming model in which the hourly loads, the hourly natural inflows are all expressed in grey number notation, is developed. The developed grey linear programming approach is applied to schedule the generation in the Taiwan power system. It is found that the proposed approach is very effective in obtaining proper hydro generation schedules in uncertain conditions. (C) 1997 Elsevier Science S.A.