Development and Operation Control of a Switched-Reluctance Motor Driven Flywheel

Abstract

This paper presents the development of a switched-reluctance machine (SRM) driven flywheel system, its charging/discharging controls, and performance evaluations. By properly setting and tuning the winding commutation instant, the same SRM can be operated as a motor and a generator in the SRM-driven flywheel system with satisfactory performances. Moreover, the hysteresis current controlled pulsewidth modulation scheme with hard freewheeling and the commutation angle dynamic shift controller are proposed to enhance the flywheel discharging generating performance. For interfacing the flywheel system to the dc microgrid, a half-bridge bidirectional dc-dc interface converter is developed. It is operated in a buck mode under flywheel charging and in a boost mode under flywheel discharging. The dynamic modeling and controller design are conducted to yield well-regulated dc output voltage under varying flywheel-driven switched-reluctance generator (SRG) speed. Finally, the measured results are given to verify the performances of the established flywheel and its interconnected operation to a wind SRG-based dc microgrid.