In an asynchronous electric motor, the rotor will always rotate with lower rotational rotation of the rotating field and therefore there will be current and torque or electromechanical torque induced. The relative difference between the rotor speeds and the stator rotating field dodge 076153 at the synchronous speed is known as “slippage”. If the motor rotates at a speed other than the synchronous speed, the winding of the rotor will cut the magnetic lines of force of the rotating field, and by the laws of electromagnetism, induced currents will circulate in it.
The higher the load, the greater the torque needed to drive it. To obtain a larger torque, the difference in speed between the rotor and the rotating field in the stator must be proportionally greater so that the induced currents and the fields produced are larger. Therefore, as the load increases, it falls to the engine speed. When the load is zero the rotor will generally rotate in synchronous rotation. The frequency of the induced current in the rotor is equal to the slippage by the frequency of the stator. At vacuum the sliding is very small, therefore, as in the rotor, its reactance and its induced electromotive force are all very small.