Flywheel energy storage system for city railway

This article makes an effort to explain practice using of stationary energy storage system based on flywheel (FESS). We are introducing two fundamental methods of utilization of the FESS for the tram transportation or trolleybus lines. The main goal of these methods is to save non-utilized energy from the DC railway and use it for covering the consumption peaks and to decrease the total power load of the traction substation from the viewpoint of the power grid. The ideal case is complete smoothening of the course of used energy. The principle of these methods is demonstrated on real data measured during the operation of the tramcar in Liberec.