Lagrange-dual-based fully distributed economic dispatch in smart grids with transmission line losses

Abstract

Economic dispatch constitutes an important element within the hierarchical control framework of smart grids. Its effective implementation is imperative for cost reduction in generation, enhancement of operational efficiency, and power systems stability. This paper tackles the distributed economic dispatch problem in smart grids with transmission line losses. First, the economic dispatch problem is transformed into its Lagrange dual problem using convex optimization theory, accompanied by a description of the strategy for addressing inequality constraints. Then, a fully distributed optimization algorithm is developed under free initial state through the fusion of nonsmooth analysis and the primal–dual method. Furthermore, based on this algorithm, a modified algorithm with lower communication overhead is presented. Finally, software simulations and hardware-in-the-loop tests are performed to verify the developed scheme.