Hello Again,
This time I am reading another nice book about SYNCHRONOUS MACHINES.
48550 Electrical Energy Technology Chapter 6.Synchronous Machines
And in page 15 is this nice Image called:
The mmf of a distributed winding on the rotor of a round-rotor generator
[IMG]
[/IMG]In the explanation of the above picture it reads...
Rotor Magnetic Field Using the method of superposition on the mmf's of the coils which form the rotor winding, we can derive that the distributions of the mmf and hence the flux density in the air gap are close to sine waves for a round rotor synchronous machine with uniform air gap, as illustrated above.
Description of the two images above: We can clearly see the rotor Magnetic Axis at top and bottom images, where bottom image is a linear spread from above image rotor with the matching numerical sequence of coils conductors (seen as a dot with crosses on right side, meaning leaving screen direction of currents, numbered 1.2.3.4.5 and small dots to the left side of screen reflecting currents entering screen and numbered 6,7,8,9,10)
We can clearly notice at the bottom image center rotor magnetic axis leads exactly to the perfect sinewave peak center values, based on mmf (magneto motive force)
In page 16 it concludes this part by the following text:
In the case of a salient pole rotor, the rotor poles are shaped so that the resultant mmf and flux density would distribute sinusoidally in the air gap, and thus the induced emf in the stator windings linking this flux will also be sinusoidal.
Regards to All
Ufopolitics
















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