As is well known, the structure of an electric motor consists of both electrical and mechanical parts, and it can also be said to be the convergence point of the two. So, its malfunction should be analyzed from two sides. The causes of motor vibration faults should also be divided into two parts. Generally speaking, motor vibration is caused by imbalance of the rotating part a, mechanical faults or electromagnetic reasons. The imbalance of the rotating parts is mainly caused by the imbalance of the rotor, coupler, coupling and drive wheel (brake wheel). The solution is to first find the equilibrium of the particles. If there are large drive wheels, brake wheels, couplings or couplings, they should be balanced separately from the rotor. Another cause is the mechanical loosening of the rotating parts. For instance, loose core brackets, failed or loose inclined keys and pins, and loose rotor binding can all cause imbalance in the rotating parts. The main mechanical part failures are as follows:
1. The shaft system of the linkage part is not aligned, the centerlines do not coincide, and the centering is incorrect. The main cause of this kind of malfunction is poor alignment and improper installation during the installation process. There is another situation where the centerlines of some interlocking parts are consistent in the cold state, but after running for a period of time, due to the deformation of the rotor support points, foundation, etc., the centerlines are damaged again, thus causing vibration.
2. There are problems with the gears and couplings connected to the motor. This kind of malfunction is mainly manifested as poor gear meshing, severe wear of gear teeth, poor lubrication of the mating wheels, skewing and misalignment of the couplings, incorrect tooth shape and pitch, excessive clearance or severe wear of the gear couplings, all of which will cause certain vibrations.
3. Structural defects of the motor itself and installation issues. This kind of fault is mainly manifested as an elliptical journal, bent rotating shaft, excessive or insufficient clearance between the shaft and the bearing bush, insufficient rigidity of a certain part of the bearing housing, base plate, foundation or even the entire motor installation foundation, loose fixation between the motor and the base plate, loose anchor bolts, and loose connection between the bearing housing and the base plate, etc. Excessive or insufficient clearance between the shaft and the bearing bush can not only cause vibration but also lead to abnormal lubrication and temperature of the bearing bush.
4. The load driven by the motor conducts vibration. For instance, the vibration of the steam turbine in a steam turbine generator, as well as the vibration of the fan and water pump driven by the motor, all cause motor vibration. Iii. Faults in the electrical part caused by electromagnetic reasons mainly include Incorrect wiring of the stator of an AC motor, short circuit of the rotor winding of a wound-rotor asynchronous motor, inter-turn short circuit of the excitation winding of a synchronous motor, incorrect connection of the excitation coil of a synchronous motor, broken bars of the rotor of a squirrel-cage asynchronous motor, and deformation of the rotor core cause uneven air gaps between the stator and rotor, resulting in unbalanced air gap flux and thus causing vibration. The causes of motor vibration are diverse. The above are just a summary of some actual faults encountered by Beidou Power during its operation.
For more questions about the generator set, please call the Beidou Power team. More than ten years of professional production and sales of power generation equipment experience, more professional engineer team to serve you, choose Beidou power is to choose rest assured, welcome on-site factory inspection.
Post time: Jul-16-2025