In AC machines the stator is generally in the form of a cylindrical tube, with a certain wall thickness. A based on stacked crowns of magnetic sheet with a toothed on its inner circle are formed the slots where the coils are housed. In the continuous current machines the stator is formed by a solid steel cylindrical frame. This frame has polar poles or pieces with corresponding coils attached to it.
Depending on the configuration of a rotating electric force device, this stator can act as a magnet (through the electromagnet effect), reacting with the armature to produce movement. In addition, the stator can also act as an armature by accepting inductors of a moving field coil located in a rotor.
The first DC generator, known as a dynamo, and the current electric motors place the field coil in the stator, while the power generation or the motion reaction coil is placed in the rotor. This is especially important because a switch in constant motion is required to ensure that the field is correctly aligned along the rotating rotor. A higher-order converter is required if the power amplification increases.
The stator for this type of device can be composed of permanent or electromagnetic magnets. If the stator is an electromagnet, the coil that drives it is known as a field coil. An alternator is also capable of generating power through multiple multiplication coil generators that have high power amplifiers. These amplifiers are connected in parallel without the need for a converter.