Are High-voltage Motors More Prone To Vibration Problems?

Are High-voltage Motors More Prone to Vibration Problems?

Compared with low-voltage motors, high-voltage motors, especially high-voltage asynchronous motors, are mostly based on cage-shaped rotor structure. During the manufacturing and operation of the motor, due to the inappropriate cooperation of mechanical structural parts, the motor may cause serious vibration, which may be radial vibration or axial vibration.

The uneven air gap between the stator and the rotor is a key factor in the vibration of the motor. In the production and processing process, when the motor base, stator core, and rotor parts have different shafts, the air gap of the motor will be uneven. After the motor is energized, it will cause electromagnetic vibration of the motor due to unilateral magnetic tension. The vibration caused by this reason, in addition to mechanical vibration, is also accompanied by low-frequency electromagnetic sound.

For motors in operation, especially those that have been repaired, due to long-term operation, the diameter of the motor bearing, bearing chamber, and bearing position may have some dimensional deviations, resulting in unreasonable cooperation between each other, resulting in motor vibration problems. For the mating parts of the inner and outer rings of the bearing, when there is a serious loosening of the mating problem, the fatal qualitative failure of the bearing heating until it burns out will also occur in a short period of time due to the bearing running ring.

For the rotor part of the motor, the rotor body loses balance due to the deformation of the rotor guide strip that occurs during the operation of the motor and the failure of the original equilibrium state. This is a common cause of failure during the operation of high and low voltage motors.

For high-voltage motors, especially those with sliding bearings, the misalignment of the magnetic centerline is the fundamental cause of the axial vibration of the motor. This is the key that must be controlled during the installation and use of high-voltage motors. In order to prevent the occurrence of similar problems, for cage-type high-voltage motors, the control of the starting process is particularly important, and it is necessary to prevent the difficulty of starting the motor due to insufficient power supply capacity.

In the analysis and inspection of motor vibration problems, the necessary project inspections should be passed to clarify the root cause of vibration. Some motor repair units are more inclined to replace bearings. Objectively speaking, bearing non-compliance will cause motor vibration problems, but bearing compliance may not solve the motor vibration problem, so in-depth comprehensive analysis is more conducive to the solution of the problem.

For electromagnetic reasons, the asymmetry of the windings and the electrical quality failure of the windings will all lead to uneven magnetic field of the motor, which will also lead to electromagnetic vibration of the motor. This vibration is more manifested as severe shaking and accompanied by a serious dull sound. There is still a difference from mechanical vibration, which can be clearly distinguished during the analysis process.