Management and modelling of battery storage systems inudmicroGrids and virtual power plants

摘要

In the novel smart grid configuration of power networks, Energy Storage Systemsud(ESSs) are emerging as one of the most effective and practical solutions to improveudthe stability, reliability and security of electricity power grids, especially in presenceudof high penetration of intermittent Renewable Energy Sources (RESs).udThis PhD dissertation proposes a number of approaches in order to deal withudsome typical issues of future active power systems, including optimal ESS sizingudand modelling problems, power udows management strategies and minimisation ofudinvestment and operating costs. In particular, in the first part of the Thesis severaludalgorithms and methodologies for the management of microgrids and Virtual PowerudPlants, integrating RES generators and battery ESSs, are proposed and analysedudfor four cases of study, aimed at highlighting the potentialities of integrating ESSsudin different smart grid architectures. The management strategies here presented areudspecifically based on rule-based and optimal management approaches. The promisingudresults obtained in the energy management of power systems have highlightedudthe importance of reliable component models in the implementation of the controludstrategies. In fact, the performance of the energy management approach is only asudaccurate as the data provided by models, batteries being the most challenging elementudin the presented cases of study. Therefore, in the second part of this Thesis,udthe issues in modelling battery technologies are addressed, particularly referring toudLithium-Iron Phosphate (LFP) and Sodium-Nickel Chloride (SNB) systems. In theudfirst case, a simplified and unified model of lithium batteries is proposed for theudaccurate prediction of charging processes evolution in EV applications, based on theudexperimental tests on a 2.3 Ah LFP battery. Finally, a dynamic electrical modellingudis presented for a high temperature Sodium-Nickel Chloride battery. The proposedudmodelling is developed from an extensive experimental testing and characterisationudof a commercial 23.5 kWh SNB, and is validated using a measured current-voltageudprofile, triggering the whole battery operative range.ud