Development of steady state and dynamic energy storage models for DIgSILENT PowerFactory

The importance of energy storage technologies is being recognised by more and more power system professionals lately. If properly designed, installed and operated, storage can provide flexibility, and be a valuable component of future electricity networks. Although regulatory and market conditions still have to be improved, the potential of energy storage is unequivocal. As power companies are seeking best practices of utilising storage units, a demand arises for accurate modelling. Present paper introduces steady state and dynamic modelling options for generic energy storage technologies, developed for DIgSILENT PowerFactory. Primary aim of the authors was to design a flexible and versatile structure that allows the user to implement arbitrary storage strategies and to compare the performance of different technological options. In the first part of the paper, an overview is given on existing models. As it is shown, majority of the models are only capable of simulating a single storage technology. In the second part of the paper, the steady state and dynamic models are detailed, emphasizing important differences compared to existing ones. Finally, selected case studies are shown to demonstrate the operation of the models under various circumstances.