Optimizing DER Aggregate Flexibility via Network Reconfiguration

TL;DR

This paper presents a novel method to optimize the aggregate flexibility of distributed energy resources by reconfiguring the distribution network, using advanced optimization techniques to significantly improve flexibility regions.

Contribution

It introduces a scalable Benders decomposition approach for optimizing network reconfiguration to enhance DER aggregate flexibility, with an exact convex reformulation and proven convergence.

Findings

Significant expansion of the aggregate flexibility region achieved

Method outperforms existing approaches in numerical simulations

Optimized topology improves flexibility across multiple scenarios

Abstract

The aggregate flexibility region of distributed energy resources (DERs) quantifies the aggregate power shaping capabilities of DERs. It characterizes the distribution network's potential for wholesale market participation and grid service provision at the transmission level. To enhance flexibility and fully exploit the potential of DERs, this paper proposes a method to optimize the aggregate flexibility region through distribution network reconfiguration. First, we formulate the ellipsoidal aggregate flexibility region characterization problem as a two-stage adaptive robust optimization problem and derive an exact convex reformulation with a large number of second-order cone constraints. By exploiting the problem structure, we propose a scalable Benders decomposition algorithm with provable finite convergence to the optimal solution. Finally, we propose an optimal reconfiguration problem for aggregate flexibility region optimization and solve it using the custom Benders decomposition. Numerical simulations on the IEEE 123-bus test feeder demonstrate that, compared to existing approaches, substantial improvements in the aggregate flexibility region can be achieved over multiple scenarios with the optimized topology.