Nowadays static UPS systems are preferred for low-power applications, although rotary UPS systems offer some interesting advantages. The rotary UPS now having only high end applications and is not available for, hospitals-critical loads like operation theatre and ICU’s, utility, small collocations, military applications- data centers , telephone equipments - mobile towers, storage devices and various data centers. In this paper, simulation investigations for a diesel rotary UPS system have been carried out using MATLAB / SIMULINK for possible implementation of this system to feed the critical loads as described above uninterruptedly. A rotary UPS uses the inertia of a high-mass spinning Flywheel (Flywheel energy storage) to provide short-term ride-through the time of power loss. The Flywheel also act as a buffer against power spikes and sags, since such short-term power events are not able to appreciably affect the rotational speed of the high-mass Flywheel, Flywheel-based UPS systems typically provide 10 to 20 seconds of protection before the Flywheel has slowed and power output stops. The name Flywheel energy ride through came from the operation of Flywheel in the rotary UPS. Flywheel is the kernel of the system described above.
A, S. N., & Ansari, M. Z. A. (2013). Simulation Investigations on Flywheel Energy Ride Through Systems. International Journal of Environmental Science : Developement and Monitoring, 4(2231), 57–62.