ENVIRONMENTALLY CONSTRAINED ECONOMIC-DISPATCH USING THE LAGRANGIAN-RELAXATION METHOD

This paper presents a general formulation of the environmentally const rained economic dispatch (ECED) problem based on the requirements of C lean Air Act Amendments of 1990 and others which may be imposed by loc al air quality regulations. The formulation considers multiple NOx con straints and incorporates the utilization of the affected units (those named in the legislation) along with SO2 constraints. It also propose s a new algorithm to solve the problem for large power systems. This a lgorithm has the ability to handle a large number of various types of linear and nonlinear environmental constraints. It is reliable, and vi able for both off-line and on-line applications. Test results on a lar ge size power system demonstrate the possible savings which can be rea lized by using the algorithm. Details of the problem formulation and t he solution technique are given in the paper.