On optimal coordinated dispatch for heterogeneous storage fleets with partial availability

TL;DR

This paper develops a scalable optimal dispatch strategy for heterogeneous storage fleets with availability constraints, providing explicit feedback policies and a characterization of feasible demand profiles for improved grid management.

Contribution

It introduces a novel feedback policy for feasible scheduling and scalable methods to maximize operational time or minimize unserved energy in heterogeneous storage fleets.

Findings

Explicit feedback policy ensures feasible scheduling.

Scalable procedures optimize fleet performance.

Time-domain characterization of feasible demands.

Abstract

This paper addresses the problem of optimal scheduling of an aggregated power profile (during a coordinated discharging or charging operation) by means of a heterogeneous fleet of storage devices subject to availability constraints. Devices have heterogeneous initial levels of energy, power ratings and efficiency; moreover, the fleet operates without cross-charging of the units. An explicit feedback policy is proposed to compute a feasible schedule whenever one exists and scalable design procedures to achieve maximum time to failure or minimal unserved energy in the case of unfeasible aggregated demand profiles. Finally, a time-domain characterization of the set of feasible demand profiles using aggregate constraints is proposed, suitable for optimization problems where the aggregate population behaviour is of interest.