A Mixed Integer Linear Programming-based Distributed Energy Management for Three-phase Unbalanced Active Distribution Network

A mixed integer linear programming (MILP)-based distributed optimization of three-phase unbalanced active distribution network is proposed. Modern distribution networks have becoming more and more active with increasing deployment of microgrids, distributed energy resources (DERs) and flexible loads. Considering various ownership and control models of microgrids, DERs and loads, a distributed optimization was formulated and solved using the alternating direction method of multipliers (ADMM) algorithm. By ADMM, the distribution management system (DMS) and these active components are coordinated through price signals, which are adjusted from the nodal power unbalance per node per phase. To enable resolution of the ADMM-based distributed optimization using MILP solver, various linearization methods were proposed to linearize the augmented Lagrangian and other nonlinear terms. Results of case studies using a three-phase active distribution system with three microgrids and several DERs and flexible loads validated the effectiveness of proposed MILP-based distributed optimization. In addition, the capability of proposed method in mitigating phase power unbalance has been demonstrated.