Electrical energy storage systems and electric vehicles for provision of fast frequency response

The last years have seen a swift increase in the proportion of connected renewable energy sources (RESs) in modern power systems to lessen unsafe levels of CO2 in the atmosphere and cut fossil fuels dependence. Despite the environmental gains of a decarbonised power system, a higher proportion of RESs could affect the grid's safe operation in at least two ways, i.e.reduce the amount of rotational inertia and increase the uncertainty of the energy balance. As RESs typically lack storage capabilities and are connected to the grid through power electronic converters (PECs), they are decoupled from the mass of synchronously rotating generators that provide inertia and counteract frequency changes, leading to quicker frequency dynamics. Furthermore, the intermittent nature of wind and solar PV makes energy balance requirements less predictable. [Continues.]