Real-Time Economic Dispatch and Reserve Allocation Using Merit Order Loading and Linear Programming Rules

Abstract

This paper presents a real-time economic dispatch algorithm suitable for on-line generation control and for study programs. The method is based on the rules of Linear Programming and the classical method of merit order loading. The basis for the algorithm is shown as a natural progression of classical optimization algorithms. Comparison with Linear Programming is included to exhibit the flexibility of the algorithm. The inclusion of a constraint for a unit or for a system wide margin (e.g., Spinning reserve) is shown. The procedure is fast, in part, since the Simplex Tableau is not explicitly stored. The method is shown in pseudo-code. This method is very suitable for real-time economic dispatch on any Energy Management System. The method requires little computer resource and is appropriate for personal computer implementation as part of a back-up automatic generation control system. The algorithm presented in this paper had been labeled the Merit Order Reduced Gradient (MORG) since it is a combination of the Merit Order Loading and the Reduced Gradient with Linear Constraints algorithms. The present implementation uses the linearized representation of the incremental heat rate curve. However, the Merit Order Reduced Gradient (MORG) algorithm can be used with any monotonically increasing incremental heat rate curve. The implicit handling of the sparse Simplex Tableau is accomplished by accounting for the contribution of each unit to each constraint.