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stator question
Flux:
You would find life very much simpler if coils had no legs, arms,feet or anything else.
A coil is a loop of wire and emf is induced in it when flux links it. The emf depends on the magnitude of the flux linkage and the rate of change. This is all you need to understand.
Thinking in terms of legs goes back to that stupid equation for the emf induced in a conductor moving through a uniform magnetic field, it is correct but doesn't apply in the real world of electrical machines. It becomes complicated to adapt it to real life and you have got yourself in a right muddle trying to come to terms with it.
Don't get back emf mixed up with all this, it applies to morors and electromagnets and is the base of Lenz's law but you needn't worry about it here.
Flux
artv:
Flux ....as the rotor (magnets) approach the coil(s) flow is induced ,......when mags exit,.... field collapses.............this is back emf..........trying to get a clear understanding...........thanks.........artv
artv:
This may be old to you ,but it's new to me,....
As electrons flow from one end to the other (regardless of direction) in the coil ,....each wire in that coil produces ,..an EM field around it (around its' outer circumfrence of each turn).......kinda link a spiarel..........
When you spin dual rotors.....you create a spinning magnetic field, on two sides...............
Introduce a conductor into ,that field , it causes electron flow.....inside the conductor.................
When the wire starts conducting it produces the same EM field...
Any time you use a wire to work your wasting the EM field...........Unless you can catch it some how ???
ghurd:
It is not 'wasted'. It just happens.
If you light a candle to make light, it gets hot. Same idea.
If you light a candle to make heat, it makes light. Same idea.
You might want to look up "super conductor",
G-
seilertechco:
ARTV, As the north pole of the magnet approaches the coil the wave form will go up on the positive side. When the coil is directly above the north pole, the wave will peak out. As it moves away from the north pole, the wave form will go down (that's half of a cycle). Then at exactly half way between the north pole and the approaching south pole the wave form will be at the zero or starting point. Then as the south pole approaches the wave will go negative. When the coil is directly over the south pole it will reach the bottom of the wave form and turn upward. Once again at the midpoint between the south pole that just passed and the next north pole approaching, it will be at the zero position. That's one complete cycle, passing both north and then south poles. And do it all over again for every set of poles per revolution.
Bridge rectifiers use diodes to take the bottom half of the wave form and mirror it to the opposite side of the neutral line, so instead of electrons going backward, they flow only in one direction. A diode is like a check valve in a water system, permitting flow in only one direction. Google bridge rectifiers. In single phase, the wave form returns to the neutral line as it passes each magnet and reaches the midpoint to the next and opposite pole. This gives a rough but workable flow of electrons in only one direction (dc). The wave looks like a series of bumps, but all in the positive direction.
Three phase has that same series of bumps but they are offset 120 degree. That gives a top of the waveform that has three bumps, but never returns to the zero line. It eliminates the pulsing of going from peak to neutral or from full speed to a full stop in flow terms.
I want to point out that when the direction of flow changes as in alternating current, one needs laminations to control heat from the change in direction of electron flow, but with DC, the electrons always flow in one direction and do not re-orient polarity (180 degree), thus laminations are not a necessity. In my case, combining electromagnets and permanent magnets, the flow is dc so laminations are not a requirement and I'm using regular old cold rolled steel. Google electro-permanent magnets for more info. Of course the power coils will be seeing ac so that does require laminations to limit hysteresis derived heat.
Perhaps this explanation makes some sense to you.
Best regards, Toby
seilertechco
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