What does the no-load loss of asynchronous motor include and what is its impact

What does the no-load loss of asynchronous motor include?

The no-load loss of an asynchronous motor refers to the power loss when the motor is not loaded and the rotor is idling, including the following aspects:

Core loss: Power loss due to hysteresis and eddy current effects in the electromagnet core.

Friction and windage losses: The power consumed by the mechanical friction and gas friction generated by the internal operation of the motor.

Resistance loss of rotor conductor: power loss caused by the existence of conductor resistance when current flows in the rotor conductor.

Induction loss: Power loss caused by the induced current in the stator due to the rotating magnetic field.

Although these losses are small when no-load, they still cause considerable power loss in large motors. Therefore, in order to improve the efficiency of the motor and reduce power loss, the no-load running time of the motor should be minimized.

What is the impact of no-load loss on asynchronous motors?

The no-load loss has a relatively small impact on the motor, but if it runs in a no-load state for a long time, it will cause the motor to overheat, increase the motor current, and reduce the motor life. Therefore, in order to save energy and extend the life of the motor, you should try to avoid running the motor in a no-load state for a long time.

How to check the no-load loss of asynchronous motor

The no-load loss of asynchronous motors can be found in the motor's technical parameters or performance curves. Usually the motor manufacturer will list the motor's no-load power and rated power and other parameters on the motor nameplate or manual, from which the motor's no-load loss can be calculated. In addition, the actual no-load loss of the motor can be calculated by measuring the motor's current and voltage, combined with the motor's rated power.