Do I even have my nomenclature correct for this type of motor?
Yes and No
Is what I'm trying to build really a 3 phase AC synchronous motor?
No, You are building an Asynchronous motor. Synchronous motors need to be spin started to bring then up to sync speed. The starting motor is called a "pony" motor. Or a wound rotor can be used. These are not common because of the cost to build and the controls needed.
Or is it really an induction motor with 3 driving phases?
Yes, Because a EMF in induced at the rotor. In the US we speak of single and three phase, but what about two? This is what adds to the confusion. I would guess your water heater runs with two 120 volt legs, ths is really two phase. Look at vector diagrams for "delta" and "star" sometimes called "Y" to get a visual on it.
I did some more reading and it almost seems like an actual 3 phase AC synchronous motor has a powered rotor, with the 3 phases on the rotor and the 3 phases on the stator out of phase, and it's that out of phase that makes it turn.
Yes, see above.
And I'm still trying to get my head around how that 'shorted rotor' with all of its 'shorted' copper bars and wires actually generate that 'counter balancing magnetic force'... Got my left hand out with the 3 fingers pointing every which way...maybe I should use my right hand?
You may have to take your shoes off for this oneone hand will not work
I scaned a few pages from one of my books "Electrical Circuits and Machinery Volume 2 Alternating Currents" Copyright 1942.
I hope you will be able to read it as the pages are getting somewhat on the yellow side.
Again there are two ways of looking at this. Both using the "shorted" idea.
1- Because of the multiple shorted circuits a large current is produced on the rotor, giving a large magnetic flux. This causing the iron between the copper to become a magnet.
2- If an iron bar is placed in a magnetic field it will take on the prperties of the magnet with one end being "N" and the other being "S". If the maget is rotated the iron bar will rotate too. The large current between the iron bars on the rotor act as a shield so each piece of iron has properties independant of the other.
Visualize the setup from the end with four poles . Every 90 degrees around the stator at any point in time there will be N,S,N,S. Looking at the rotor as a whole, an inductor with multiple high current shorts.
The thing with 3 phase and 120 degress between each phase mahes a rotating field with lets say very small gaps. You might think of a stepper motor setup with very small steps.
Single and two phase motors need an extra winding to start to "throw things out of phase" and some times to keep things out of phase. ( built in phase converters ) Start caps and run caps are sometime hooked here.
I hope I am not making this more confusing.
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