Experimental Ball Bearing Impedance Analysis Under Different Speed and Electrical Conditions

Ball bearings are commonly used in inverter-driven electrical machines, where they can be subject to high-frequency common-mode currents that accelerate their degradation. This article investigates the impact of shaft speed, voltage amplitude, and frequency on bearing impedance, including during discharges, with aim provide an experimentally validated approach model behavior as a function operating conditions. analysis help development improved models predict electric drives. A dedicated experimental setup, completely isolated from ground, is presented. It proposes dielectric plate bolts insulate support (which connected ground), coupling dyno bearing, sheets brush holder ground. Different amplitudes applied between inner outer raceways for several speeds. The measured impedance amplitude phase, currents, voltages Due large amount data, statistical proposed studying bearing. simple presented interpretation measurements. shows have significant discharge ball bearings, especially certain speeds strongly affecting phase breakdown state.