Power compensation mechanism for AMB system in magnetically suspended flywheel energy storage system

Abstract

The active magnetic bearing (AMB) system is the core part of magnetically suspended flywheel energy storage system (FESS) to suspend flywheel (FW) rotor at the equilibrium point, but the AMB system needs power supply system to suspend FW rotor. The stable suspension of FW rotor cannot be guaranteed if the on-board power supply system fails to work, so the unstable FW rotor causes fatal damage to magnetically suspended FESS. Therefore, an off-board power supply system is designed to maintain the stable suspension of FW rotor when the on-board power supply system fails to work. Simultaneously, the dynamic braking of FW rotor is realized by discharge of magnetically suspended FESS, so dynamic displacements of FW rotor are kept at equilibrium status. Simulation and experiment are conducted to verify that the off-board power supply system timely restores AMB system, and dynamic displacements of FW rotor are timely returned to the equilibrium point.