Two-Layer Optimal Electricity Trading Method for Distribution Networks with Multi-MG

Abstract

This paper proposes a distributed trading strategy for microgrids based on a Stackelberg game to enhance the operational benefits of distribution networks (DNs) and microgrids (MGs) while reducing microgrid energy costs. First, we establish a multi-objective two-layer optimization trading model for DN-MG interaction based on the Stackelberg game. In this model, the upper layer focuses on maximizing agent profits through a DN trading model, while the lower layer aims to minimize operator costs through an MG energy optimization model. Next, the Karush–Kuhn–Tucker conditions are applied to reformulate the two-layer model into a single-layer model. Subsequently, linear transformations are used to convert the model into a mixed-integer linear programming model. The transformations aim to address the nonlinear issues arising from multivariable coupling between the upper and lower-layers trading models. Simulation results indicate that the proposed trading strategy significantly increases the profits of DN agents while lowering the operational costs of MGs. This approach offers valuable insights for decision-making in electricity markets that involve microgrids.