How to solve the vibration problem of the motor?
Motor and all other machinery and equipment, in the operation process there is energy, heat, wear and tear, vibration and other physical and chemical parameters of the transfer and change, these changes in information directly and indirectly reflect the operating state of the motor, and vibration can be sensitive to reflect the operating state of the motor.
There are many factors that lead to motor vibration, including the quality of the motor itself, the matching of the motor and equipment, and the actual use of the working conditions and so on.
In terms of the motor itself, from the processing of parts, winding fixed, rotor balancing, parts and components with the link to control, can ensure that the inherent mechanical vibration characteristics of the motor to meet the requirements. In addition to the vibration caused by mechanical factors, electrical causes of vibration is also more common, such as stator and rotor air gap uneven vibration, stator and rotor core is not aligned with the axial runout caused by the power supply frequency caused by resonance and so on. Vibration analysis caused by electrical factors may be directly judged by cutting off the power supply.
In particular, it should be reminded that different conditions of use of the motor vibration requirements are not the same, which in turn requires the overall strength of the motor to put forward special requirements, therefore, the supply and demand sides of the full communication is particularly important.
Motor vibration cause analysis
● Rotor, coupler, coupling, drive wheel uneven street caused.
● Loose core support, oblique Jian, pin failure and loosening, wire-wound rotor lashing is not tight, rotor balance is not good, resulting in the rotating part of the imbalance.
The linkage part of the object system is not centered, the center line does not coincide, centering is not correct. The cause of this failure is mainly due to poor centering and improper installation during the installation process.
●The centerline of the linkage part is coincident in the cold state, but vibration occurs after a period of operation due to the rotor pivot point, deformation of its base, etc., and destruction of the centerline.
●The gears and couplings connected with the motor are faulty, the gears bite poorly, the gear teeth are badly worn, the coupling is skewed and misaligned, and the tooth coupling teeth are not in the right shape or pitch, and the clearance is too large or badly worn, which will cause a certain amount of vibration.
● Defects in the structure of the motor itself, such as oval journal, bent rotor shaft, excessive or small clearance between the shaft and the shaft tile, insufficient rigidity of the bearing seat, foundation plate, a part of the foundation or even the entire motor mounting base.
● Inadequate fixing between the motor and the foundation plate, loose foot bolts, looseness between the bearing housing and the foundation plate, etc.
● Excessive or small clearance between the shaft and the shaft tile can cause not only vibration but also abnormal lubrication and temperature of the shaft tile.
● Load-conducted vibration of the motor-drawn load. For example, vibration of fans and pumps dragged by the motor causes motor vibration.
● AC motor stator wiring error, wire-wound asynchronous motor rotor winding short-circuit, synchronous motor excitation winding turn-to-turn short-circuit, synchronous motor excitation line circular coupling error, cage-type asynchronous motor rotor broken bars, rotor core deformation caused by stator and rotor air gap is not even, resulting in air gap flux imbalance and thus causing vibration.
