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MPaulHolmes · 08-23-2014, 11:47 PM

I have no official motor in mind. I'm just lying in wait, ready to pounce like a puma, once I save up enough money.

The beauty of those ring capacitors is, "occasional spikes over 600v are not a good reason to get a higher voltage ring cap." That's a quote from one of the SBE engineers. They were trying to push the 450v cap on me when I was going to run it at 300v. They don't need much derating at all.

The 3 phases to neutral are 120Vac. But I think that only makes sense when talking about filtered real life sine waves that are 120 degrees apart. Starting with DC, we are just getting pwm'ed square waves that instantaneously don't look like 120Vac from phase to neutral. They have to be filtered before looking like that.

EDIT: Or maybe it really is 120Vac sine waves, 120 degrees out of phase that are across each phase coil, but the phase coil voltage (to neutral) is not accessible to us. Sure, let's go with that! haha.

08-23-2014, 11:47 PM	#1000 (permalink)
MPaulHolmes PaulH Join Date: Feb 2008 Location: Maricopa, AZ (sort of. Actually outside of town) Posts: 3,832 Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000 Thanks: 1,362 Thanked 1,202 Times in 765 Posts	I have no official motor in mind. I'm just lying in wait, ready to pounce like a puma, once I save up enough money. The beauty of those ring capacitors is, "occasional spikes over 600v are not a good reason to get a higher voltage ring cap." That's a quote from one of the SBE engineers. They were trying to push the 450v cap on me when I was going to run it at 300v. They don't need much derating at all. The 3 phases to neutral are 120Vac. But I think that only makes sense when talking about filtered real life sine waves that are 120 degrees apart. Starting with DC, we are just getting pwm'ed square waves that instantaneously don't look like 120Vac from phase to neutral. They have to be filtered before looking like that. EDIT: Or maybe it really is 120Vac sine waves, 120 degrees out of phase that are across each phase coil, but the phase coil voltage (to neutral) is not accessible to us. Sure, let's go with that! haha. __________________ kits and boards Last edited by MPaulHolmes; 08-24-2014 at 12:24 AM..