Power System Economic Dispatch

Economic dispatch (ED) is at the heart of economic operation of a power system. In addition to maintaining the system reliability, meeting the forecasted system load at the lowest possible cost is one of the key goals in power system operation. The ED problem primarily depends on the generating unit cost function. However, the cost versus power relationship can be represented in four different types of curves: input‐output curve; fuel cost curve; heat rate curve and incremental cost curve. Mathematically, the ED problem can be formulated using the constrained static optimization problem. For simplicity, the losses can be initially neglected, then P
_L
= 0. The problem can be considered without the network, where all generators and loads are connected to a single bus bar. This chapter presents three methods to solve the ED problem: lambda iteration method, Newton‐Raphson method and reduced gradient methods.