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Old 12-14-2014, 05:58 PM   #1461 (permalink)
MPaulHolmes's Avatar
Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
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Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
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Holy cow, I take a break from the internet for a day and I miss out on all sorts of stuff! haha. I modified an encoder that was for my old ACIM, but forgot that it has no index pulse, so it won't work. It's a shame too, because it was not easy doing what I did to get that thing to go on a larger post. The mods were extensive.

I don't really understand what the reluctance flywheel thing is, but it would be awesome to get it working and be inexpensive.

W.R.T. field weakening, here's what I did and it works well on the bench with a flywheel:

The allowable voltage can be thought of as a circle of radius R. Let Vd and Vq be the "direct" and "quadrature" voltages. When (Vd, Vq) lies outside that circle of radius R, you don't have enough voltage to allow Id--> IdRef and Iq--> IqRef. So, you figure out the scale factor to shrink (Vd, Vq) down to land right on the circle of radius R. Then, you multiply IdRef and IqRef by something proportional to that scale factor. That's the "field weakening" part. Then, allow IdRef and iqRef to ramp back to where they really want to be (what I call IdRefRef and IqRefRef).

kits and boards
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