Week-Ahead Dispatching of Active Distribution Networks Using Hybrid Energy Storage Systemsorks Using Hybrid Energy Storage Systemsweek-Ahead Dispatch

The increasing penetration of stochastic electricity generation, along with the subsequent displacement of classic reserve providers has increased the interest in the control of flexible balancing assets. In this context both daily and weekly time horizons have to be considered. To address the issues associated with uncertain stochastic generation, this paper presents a week-long scheduling approach for active distribution networks (ADNs) hosting hybrid energy storages, composed by a hydrogen energy storage system (HESS) and a battery energy storage system (BESS). The intraday control of these assets is realized by a multi-level MPC. Specifically, the inclusion of a pressurized HESS allows to balance energy over longer time periods. We also discuss the computational challenges associated with the weekly time horizon and the use of a HESS that exhibits different dynamics than a BESS. The optimal schedule consists of an active power trajectory at the grid connection point (GCP), called the dispatch plan, and the unit commitment schedule of a PEM fuel cell and electrolyzer system interfacing the electricity network with the HESS. In the tracking stage, the upper layer MPC computes a storage target accounting for the full problem horizon, while the lower layer computes the controllable resource setpoints to minimize the dispatch tracking error in each period. A numerical experiment shows the effectiveness of the proposed scheduling and control to accurately compute and track a dispatch plan over a full week.