Fast $\lambda$ -Iteration Method for Economic Dispatch With Prohibited Operating Zones

This letter presents a new method, the fast λ-iteration (FλI) method, to solve the economic dispatch (ED) problem considering the prohibited operating zones (POZs) and ramp rate limits of generation units. Necessary conditions for the optimal solution of the ED problem are presented and proved. The efficiency of the method has been verified on a 15-unit system and a Korea 140-unit system.