Dynamic Analysis and Control of an Energy Storage Flywheel Rotor with Active Magnetic Bearings

Flywheel energy storage is a promising technology for providing intermediate energy storage. An energy storage flywheel is supported by active magnetic bearings (AMBs) to achieve high speed running and increase energy efficiency of the energy storage system. The configuration of the flywheel rotor is complex and its rotor dynamic behavior influences the running of the AMB rotor greatly, including its strong gyroscopic effects and bending vibration modes whose frequencies are within the rotor's operation speed range. Careful dynamic analysis was performed for the flywheel rotor. Based on the analysis results, an effective controller design for the AMBs was performed. An advanced controller with local damping enhancement and cross feedback technologies was successfully designed. The controller could well restrain the negative influence from the gyroscopic effects, suppress the bending mode vibration and achieve a stable suspension of the rotor in the whole operation speed range. Experimental results were provided and proved the effects of the analysis and the controller.