Advantages and disadvantages of asynchronous motors
Asynchronous motor vibration and noise Asynchronous motors are widely used mainly because of their advantages: simple structure, reliable operation, easy manufacture, low price, ruggedness, high efficiency and quite good working characteristics.
The main disadvantage of asynchronous motors is that it is not economically smooth in a wide range and that it must absorb the lag of reactive power from the grid. In the motor, the main magnetic flux enters the air gap substantially in the radial direction and generates a radial force in the stator and the rotor, thereby causing electromagnetic vibration and noise. At the same time, tangential moment and axial force are generated, causing tangential vibration and axial vibration. In order to calculate the electromagnetic noise of the motor and analyze and control these noises, it is necessary to know the source of these noises and vibrations, that is, the force waves that generate vibration and noise. At present, the magnetic field of the motor can be calculated by CAE simulation analysis.
The vibration of the motor is the most concerned issue in the current motor structure design, which consists of three parts: electromagnetic vibration, mechanical vibration and gas vibration.
Electromagnetic vibration: It is the interaction of the magnetic field in the air gap of the motor, which produces electromagnetic force that changes with time and space on the rotor and stator, causing the motor to vibrate.
Mechanical vibration: Vibration caused by mechanical imbalances such as rotor imbalance, bearings, etc.
Gas vibration: Vibration caused by air flow or aerodynamic forces in the ventilation components of the motor.
