A Two-Layer Near-Optimal Strategy for Substation Constraint Management via Home Batteries

Abstract

Within electrical distribution networks, substation constraints management requires that aggregated power demand from residential users is kept within suitable bounds. Efficiency of substation constraints management can be measured as the reduction of constraints violations w.r.t. unmanaged demand. Home batteries hold the promise of enabling efficient and user-oblivious substation constraints management. Centralized control of home batteries would achieve optimal efficiency. However, it is hardly acceptable by users, since service providers (e.g., utilities or aggregators) would directly control batteries at user premises. Unfortunately, devising efficient hierarchical control strategies, thus overcoming the above problem, is far from easy. We present a novel two-layer control strategy for home batteries that avoids direct control of home devices by the service provider and at the same time yields nearoptimal substation constraints management efficiency. Our simulation results on field data from 62 households in Denmark show that the substation constraints management efficiency achieved with our approach is at least 82% of the one obtained with a theoretical optimal centralized strategy. NOMENCLATUREs EDN substation T s set of time slots for substation s U set of houses (users) t time slot (element of T ) u house (element of U ) T u set of time slots for house u; note that, for all notation depending on an house index u, if the house is understood, u is not shown T u,P set of time slots in T u in which the EV is plugged-in on house u τ l duration (in minutes

Design and Field Implementation of a Hierarchical Control Solution for Residential Energy Storage Systems

“…In a centralised solution, the aggregator hosts the entire controller. This may achieve optimal efficiency, but the full control of the ESS at the end-user premises would be hardly accepted [23]. Moreover, the real-time management of the local resources is very challenging, requiring a fast, reliable, and robust communication network, and specially when the aggregator is geographically located in a different place and operate the overall controller from a cloud control platform.…”

“…Distributed implementation solutions are gaining potential interest. While enabling to overcome the shortcoming of centralised and decentralised solutions, it offers a high level of flexibility for designing the control solution and path the way toward better integrating residential prosumers into the transactive energy market [23]. The concept is recently addressed, and the distributed implementation of a control solution for optimally managing residential prosumers' resources using sophisticated forecasting tools in the cloud is still an open topic.…”

“…A distributed implementation of two-layer control strategy of residential ESS for substation constraint management is proposed in [23].. The upper layer is designed to manage the aggregated power output.…”