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Confusion understanding induction motors

Confusion understanding induction motors

Confusion understanding induction motors

(OP)
Hi everyone,

Does anyone know of a good illustration, animation or video showing the CORRECT inner mechanism of induction motors?

I'm mainly trying to get my head around how induction motors are wound. I can't understand in 3D space, how Flemming's left hand rule aligns with the direction of the lines of flux, induced current and rotor bars in an induction motor (which I believe is a.k.a. asynchronous motor).

Too much info from the web has confused me. For example:
In this video (youtube.com/watch?v=LtJoJBUSe28) the lines of flux from stator windings are shown about axes PARALLEL to the shaft
But in this one, (../watch?v=HWrNzUCjbkk), the lines of flux are about axes PERPENDICULAR to the shaft.
According to this guy, (../watch?v=EWZkFX48vu0) rotor has coils. Where are the rotor bars gone?

Am I missing something?

RE: Confusion understanding induction motors

That video has a lot of problems...


"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington

RE: Confusion understanding induction motors

Quote:

In this video (youtube.com/watch?v=LtJoJBUSe28) the lines of flux from stator windings are shown about axes PARALLEL to the shaft
I spent (wasted?) time to watch the video and don't see what you're saying. They show current parallel to the axis and flux perpendicular (encircling) the current.

Quote:

According to this guy, (../watch?v=EWZkFX48vu0) rotor has coils. Where are the rotor bars gone?
Wound rotor induction motor has coils.
Sync motor rotor has coils (or wound poles for salient machines)
dc motor rotor has coils.
Squirrel cage induction motor rotor has bars.

=====================================
(2B)+(2B)' ?

RE: Confusion understanding induction motors

(OP)
Electricpete, your comments about coils have clarified some things. Thanks

But regarding your comment...

Quote:


They show current parallel to the axis and flux perpendicular (encircling) the current.

Thats's what I actually meant. Flux perpendicular (encircling) the current is the same as the flux runs "about" the line of current. In other words, the flux runs about the axis which is parallel to the shaft. (Because line of current is parallel to the shaft)

My main purpose was to say that the directions differ from one video to the other. So which is the correct one?

RE: Confusion understanding induction motors

Think of the flux path as circular with the plane of the circle perpendicular to the shaft. Part of the circle will be in the rotor and part of the circle will be in the stator. No usful flux parallel to the shaft.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Confusion understanding induction motors

That video is a shame. Don't watch it!

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Confusion understanding induction motors

Nice link Desertfox thumbsup2

RE: Confusion understanding induction motors

Hi flexoprinting

your welcome and thank you!

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