Opposites attract! – If AC motors could talk, this is what they’d be saying all day long and the reason for it is very strong. Mainly, AC motors base their work on magnetic fields that are specifically controlled as to urge the main magnet to follow the surrounding ring of electromagnetic coils, thus creating rotation.
In order for this rotation to keep going, the north and the south poles of the magnetic fields need to be facing each other so that attraction can be created. We can call this attraction “the chase”, since we need to constantly change the status of one magnet’s end to provoke the main one to keep up with the pace.
As the middle, arrow-like permanent magnet rotates, the north end of a magnet is attracted to the south, the south end is attracted to the north, whereas the south repels the south and the north repels the north. So, the magnet in the middle will desperately try to align itself with the opposite end and while the alteration of current is not letting it align, it will go on rotation and this is basically the simplest and the best introduction to AC motors. The only difference between this simplified explanation and its more complicated version is that instead of rotating any components, AC motors use alternating current. The alternating current is to be wrapped around a magnet, creating a set of electromagnets.
The initial alignment is triggered by positive current that is coming through one of the wires. This is how the center magnet that’s on a pin tries for the first time to align itself with two electromagnets of one of the sets. Since AC currents operate on a loop, the electromagnets that initially attracted the one in the middle need to be deprived of their power. But the central magnet mustn’t stay in that position, therefore, once more we’ll need to witness the change of current and yet a new creation of opposite poles – the ones that were deprived of current will again enter their magnetic prime. On the other hand, the current in the other two coils needs to be increased. This equals brand new north-south pole creation, thus changing the direction of the magnet in the center.
Just as with all types of motors, AC motors comprise a stator and a rotor for obtaining electromagnetic induction – the rotor being placed inside the stator as the stator creates magnetic field that forces the rotation of the rotor.
Just as much as life itself, the existence of AC motors is a consequence of constant change and rearrangement and to know what’s in the core of them is what a true introduction to AC motors really is.
