Condition monitoring of high-speed flywheel using modal analysis method

Due to the availability of new materials and enhanced production processes, compact flywheel energy storage systems will become a competitive alternative to battery systems in hybrid vehicles. These new high-speed composite flywheels are highly stressed on the rotor side and therefore require condition monitoring for a save and reliable operation. This paper presents a monitoring approach based on modal analysis. A cylindrical test object, representing the simplification of an external flywheel rotor, is analyzed. A numerical simulation of the test object is performed using Comsol Multiphysics software, and practical measurements are carried out to verify the basic assumptions underlying the proposed measurement approach. Simulation and experimental results are used to assess the applicability of the approach for condition monitoring of flywheel rotors. Flywheel, mechanical energy storage, modal analysis, condition monitoring.