The induction electric motors have a single winding in the stator and this winding generates a magnetic field that alternates along with the alternations of the current. In this case, the triggered motion is not rotating.
In single-phase windings of the type fed by a current, a magnetomotive force is distributed spatially under a pole in the form of a ladder, martin best prices where by chance only one pole is represented. The same curve repeats for the other poles, alternating in turn the direction of the magnetic field, that is, negative poles alternate with positive ones. The field of most interest is that which is caused by the fundamental component of the ladder curve.
The three-phase windings of the three-phase induction motor (synchronous or asynchronous) have a winding consisting of three phase windings, ie a three-phase winding, the magnetic axes of which are offset by 120º in the space between them and are maintained by a balanced voltages, also out of phase with 120º electrical over time and with equal amplitudes. Both the stator and the rotor used in the motor are made up of sheets of ferromagnetic material with grooves, the winding of the rotor being of the squirrel cage type and the coiled or wound rotor type.