Switched reluctance machine in a flywheel energy storage system for grid applications

The increasing insertion of intermittent energy sources into the energy grid is leading to new challenges in terms of stability and control of such systems. In this scenario, mechanisms capable to store energy can be employed to improve its quality. The use of a Flywheel Energy Storage System (FESS) is suitable for applications requiring high power density for short periods of time. This article presents the modeling, simulation and analyzes for the control of a Variable Reluctance Machine applied to a FESS, as well as its connection to the power grid through a back-to-back converter. The control of the DC-link is made by the grid side converter, while the machine side converter controls the current injected into the grid/consumed by the machine. Matlab/Simulink® was used in the modeling, and the results show bidirectional operation, with good performance of the designed controllers.