In modern electric equipment,especially electric vehicles,inverter control systems can lead to complex shaft voltages and bearing currents.Within an electric motor,many parts have electrical failure problems,and among...In modern electric equipment,especially electric vehicles,inverter control systems can lead to complex shaft voltages and bearing currents.Within an electric motor,many parts have electrical failure problems,and among which bearings are the most sensitive and vulnerable components.In recent years,electrical failures in bearing have been frequently reported in electric vehicles,and the electrical failure of bearings has become a key issue that restricts the lifetime of all‐electric motor‐based power systems in a broader sense.The purpose of this review is to provide a comprehensive overview of the bearing premature failure in the mechanical systems exposed in an electrical environment represented by electric vehicles.The electrical environments in which bearing works including the different components and the origins of the shaft voltages and bearing currents,as well as the typical modes of electrical bearing failure including various topographical damages and lubrication failures,have been discussed.The fundamental influence mechanisms of voltage/current on the friction/lubrication properties have been summarized and analyzed,and corresponding countermeasures have been proposed.Finally,a brief introduction to the key technical flaws in the current researches will be made and the future outlook of frontier directions will be discussed.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51822505 and 51527901)Tsinghua University Initiative Scientific Research Program(Grant No.2019Z08QCX11)Beijing Natural Science Foundation of China(Grant No.3182010)
文摘In modern electric equipment,especially electric vehicles,inverter control systems can lead to complex shaft voltages and bearing currents.Within an electric motor,many parts have electrical failure problems,and among which bearings are the most sensitive and vulnerable components.In recent years,electrical failures in bearing have been frequently reported in electric vehicles,and the electrical failure of bearings has become a key issue that restricts the lifetime of all‐electric motor‐based power systems in a broader sense.The purpose of this review is to provide a comprehensive overview of the bearing premature failure in the mechanical systems exposed in an electrical environment represented by electric vehicles.The electrical environments in which bearing works including the different components and the origins of the shaft voltages and bearing currents,as well as the typical modes of electrical bearing failure including various topographical damages and lubrication failures,have been discussed.The fundamental influence mechanisms of voltage/current on the friction/lubrication properties have been summarized and analyzed,and corresponding countermeasures have been proposed.Finally,a brief introduction to the key technical flaws in the current researches will be made and the future outlook of frontier directions will be discussed.