Decentralized Voltage Optimization Based on the Auxiliary Problem Principle in Distribution Networks with DERs

This paper addresses the problem of optimizing voltage profile radially-operated distribution systems by acting on active and reactive powers provided distributed energy resources (DERs). A novel optimization procedure is proposed adopting a decentralized control strategy. To this aim, centralized (VOP), minimizing distance all nodal voltages from their reference values, firstly formulated as strictly-convex quadratic program. Then, VOP rewritten partitioning network into zones (VCZs) with pilot nodes. overcome lack strictly convexity determined reduction to nodes, dual working augmented Lagrangian function reformulated iteratively solved method multipliers. Finally, fully-distributed solution obtained applying algorithm based auxiliary principle, which allows for solving in each VCZ programming small dimension drive solutions toward overall optimum an iterative coordination process that requires exchange among VCZs only scalar values. The effectiveness feasibility have been demonstrated via numerical tests IEEE 123-bus system.