New costs optimization concepts for unit commitment and economic load dispatch in large scale power systems

Costs optimization in unit commitment (UC) and economic load dispatch (ELD) lead to remarkable saving in the power system operational cost. For this reason, UC and ELD main problems are to minimize the total fuel cost to obtain the maximum total profit and finding fast computation simulation time for the scheduling program. Lagrangian relaxation (LR) has become one of the best solution methods in solving the UC and ELD problems. This approach has been proved more efficient and easier than other methods in solving large-scale problems. When applying LR, the dual function needed to be updated at the higher level. Lately, bundling method (BM) is one of the best solution methods to Lagrangian dual problem. This paper presents combination of LR technique, BM and interior point method for solving the UC and ELD problems. It will also explore the best possible way of updating Lagrangian multipliers with minimum computation time using fast programming techniques.