Scarlett asked in Science & MathematicsPhysics · 2 years ago

# What is in a electric motor?

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• 2 years ago

There are many different types of motor.

The most basic DC types have a set of coils along an iron core (the armature) which is fitted inside a casing that has permanent magnets.

http://www.dynamicscience.com.au/tester/solutions1...

The coil connections go to copper segments on the commutator (the smaller cylindrical section) and as the armature rotates, the carbon brushed that bring in power are continuously connected to different coils, always in the right orientation so the power through them keeps pulling the armature around.

More powerful or special purpose motors can have electromagnet coils in place of the permanent magnets to provide the "field".

Many AC motors only have field coils, called stator in that case.

https://i.stack.imgur.com/gULnx.jpg

Some kind of arrangement is used to make the magnetic field rotate.

That can just be three phase power, which rotates inherently, or a capacitor system that provides a phase shift from one winding to another.

Some (Shaded pole motors) use small thick copper shorting bands, which cause an "eddy current" and gives a rotating effect.

They are common in low-load things like fans and record players.

http://www.edisontechcenter.org/ElectricMotors/sha...

With all those type of AC motor, the rotor is a "Squirrel cage" design, with copper (or sometimes aluminium) bars along it, all connected together at each end.

The power to produce the magnetic field in the rotor comes from the stator, with the coil(s) on that and the loops in the rotor acting like a transformer and inducing a current in the rotor conductors.

The squirrel cage arrangement is set in to or cast directly in to an iron frame, to increase the magnetic fields. See the source links.

There are other types such as "Brushless DC, which have a stator similar to a three phase motor but with a permanent magnet as the rotor. Applying power to the correct combination of coils can force the rotor to any angle - and with many types, a sensor on the rotor tells the control electronics exactly what the rotor angle is, so the electronics can apply power to turn it as needed.

• oubaas
Lv 7
2 years ago

Stator, rotor with shaft, end shields , bearing/s , terminal box

• Anonymous
2 years ago

A coil of wire that spins inside some magnets.

• Mark
Lv 7
2 years ago

Strands of insulated copper wires wound around a magnet.