With the increasing use of AC motors, we should be aware of and prevent the following problems when Customized motor universal:
1. Causes of axial current: magnetic field asymmetry;There are harmonics in the supply current;Poor manufacturing and installation, uneven air gap due to rotor eccentricity;There is a gap between two semicircles of detachable stator core;The number of pieces of stator core with fan - shaped stack is not suitable.
Harm: the motor bearing surface or ball ball is corroded, the shape range is punctured microporous, the bearing operation performance deteriorates, the friction loss and the heat increase, finally causes the bearing to burn out.
2. Prevention: eliminate pulsating magnetic flux and power harmonic (such as installing AC reactor on the output side of frequency converter;When the motor is designed, the housing and base of the sliding bearing shall be insulated, and the outer ring and end cover of the rolling bearing shall be insulated.
3. Why can't general motors be used in plateau areas?
Altitude has adverse effects on motor temperature rise, motor corona (high voltage motor) and commutation of DC motor.Attention should be paid to the following three aspects:
(1) With high altitude, the higher the temperature rise of the motor, the smaller the output power.But when the temperature decreases with altitude, it compensates for the effect of altitude on temperature rise, the rated output power of the motor can be unchanged;
(2) Anti-corona measures should be taken when the high-voltage motor is used on the plateau;
(3) The elevation is not favorable to the commutation of the DC motor, so pay attention to the selection of carbon brush materials.
