Flywheel energy storage systems (FESS) are considered environmentally friendly short-term energy storage solutions due to their capacity for rapid and efficient energy storage and release, high power density, and long-term lifespan. These attributes make FESS suitable for integration into power systems in a wide range of applications.
Moreover, flywheel energy storage system array (FESA) is a potential and promising alternative to other forms of ESS in power system applications for improving power system efficiency, stability and security . However, control systems of PV-FESS, WT-FESS and FESA are crucial to guarantee the FESS performance.
To solve the lack of inertia issue, this paper proposes the method of using flywheel energy storage systems (FESSs) to provide the virtual inertia and frequency support. As compared with batteries, flywheels have a much longer lifetime and higher power density.
By regulating the speed of the flywheel in proportion to the grid frequency, the flywheel serves as an energy buffer that absorbs and releases its kinetic energy to provide inertia support. Furthermore, the design methods of the virtual inertia emulated by FESSs are described in detail.
Flywheel energy storage (FES) works by accelerating a rotor (flywheel) to a very high speed and maintaining the energy in the system as rotational energy.
There are losses due to air friction and bearing in flywheel energy storage systems. These cause energy losses with self-discharge in the flywheel energy storage system. The high speeds have been achieved in the rotating body with the developments in the field of composite materials.
OverviewPhysical characteristicsMain componentsApplicationsComparison to electric batteriesSee alsoFurther readingExternal links
Compared with other ways to store electricity, FES systems have long lifetimes (lasting decades with little or no maintenance; full-cycle lifetimes quoted for flywheels range from in excess of 10, up to 10, cycles of use), high specific energy (100–130 W·h/kg, or 360–500 kJ/kg), and large maximum power output. The energy efficiency (ratio of energy out per energy in) of flywheels, also known as round-trip efficiency, can be as high as 90%. Typical capacities range from 3 kWh to 1…