Market mechanism to enable grid-aware dispatch of Aggregators in radial distribution networks

TL;DR

This paper introduces a market-based optimization framework enabling Aggregators to compete for capacity in distribution networks, ensuring grid safety while maximizing flexible resource revenue through a convex approximation approach.

Contribution

It proposes a novel grid-aware capacity allocation mechanism that incorporates AC constraints and adapts transmission market concepts to distribution networks.

Findings

Effective capacity allocation in IEEE test networks

Maintains network constraints while maximizing aggregator revenues

Demonstrates scalability and practical applicability

Abstract

This paper presents a market-based optimization framework wherein Aggregators can compete for nodal capacity across a distribution feeder and guarantee that allocated flexible capacity cannot cause overloads or congestion. This mechanism, thus, allows Aggregators with allocated capacity to pursue a number of services at the whole-sale market level to maximize revenue of flexible resources. Based on Aggregator bids of capacity (MW) and network access price ($/MW), the distribution system operator (DSO) formulates an optimization problem that prioritizes capacity to the different Aggregators across the network while implicitly considering AC network constraints. This grid-aware allocation is obtained by incorporating a convex inner approximation into the optimization framework that prioritizes hosting capacity to different Aggregators. We adapt concepts from transmission-level capacity market clearing, utility demand charges, and Internet-like bandwidth allocation rules to distribution system operations by incorporating nodal voltage and transformer constraints into the optimization framework. Simulation based results on IEEE distribution networks showcase the effectiveness of the approach.