REDUCED ORDER MODEL OF A FLYWHEEL ENERGY STORAGE SYSTEM FOR EFFICIENT ELECTROMAGNETIC TRANSIENT SIMULATION

In this paper, a reduced flywheel energy storage system (FESS) model for efficient EMT-Type simulation in developed in the PSCAD simulation environment. The developed model considers an average value converter model for the grid side converter while a first order model representation of the flywheel is used for the machine side. The developed reduced model preserves speed and dc link voltage regulation, usually only considered in a detailed flywheel model, allowing the tracking of the FESS state of charge. The origin of minor discrepancies observed between results obtained with the reduced and detailed FESS models are also discussed. The gains brought by the simplistic FESS representation, in terms of computing efficiency and numerical stability for long time-steps, is assessed by comparing simulation results with a detailed implementation of a FESS in a time-restricted environment.