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Old 06-30-2009, 06:31 PM
pneuphysics pneuphysics is offline
Join Date: Jun 2009
Posts: 44
To MileHigh

MileHigh > For your unrectified waveform: Start below the second "0" in the fist "30.02Hz". That's the beginning of your "sine wave", it's not the middle of a folded-down peak like you think.

Me > I had no such thought - sine wave measurement IMHO starts as the wave crosses the zero point upward to the first peak and continues until the following negative peak comes up through the zero point. I can only assume you missed my point on the paper doll exercise.

MileHigh > Suppose the coils are starting to see "N-S" here. The spike you see slightly left of center of the "2" is the positive peak of your sine wave. Then you see the zero-cross and the negative peak of your sine wave. The next sine wave starts below the "H" and this time it is upside-down because the rotor has rotated by 180 degrees and now the coils see the beginning of the opposite polarity, "S-N". Since the magnetic polarity is now reversed, you see a mirror-image sine wave, almost like you swapped the leads. In this case you swapped the polarities.

Me > Yes this is my take too.

So that's the waveform: sine wave, inverted sine wave, sine wave, etc. I am using the term "sine wave" very loosely here.

Me > Yes this is my take too.

If you are scratching your heads here I suggest that you do some Wikipedia reading up on this stuff. For example, do you know why it barely resembles a sine wave? You would be much better with your future research if you understand this important concept first. I am too tired to go any further...

Me > I understand my design - i was just struct by the visual i tried to convey by the drawing exercise.
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