EcoModder Forum My Random Eco(no)-Related Things Thread

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Firefly EV - '98 Pontiac Firefly EV
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Quote:
 The synchronous speed for an AC motor is determined by the power supply frequency, and the number of poles in the motor winding. The synchronous speed can be calculated as: n = f (2 / p) 60 (1) where n = shaft rotation speed (rev/min, rpm) f = frequency of electrical power supply (Hz, cycles/sec, 1/s) p = number of poles Electric motors - Synchronous speed vs. frequency and no. poles
I'd hazard it would only be running at like 600 rpm due to the number of coils in it. At 40rpm/v, it would only have 15v of back EMF, and the rest of the 208v or whatever it peaks at would have to be dissipated across the coils. It would get hot in a hurry.

The reasonable thing to do is to check the frequency of the output when spinning it. I'll do that next time I'm mucking around with it.

Edit:
1200rpm.

It's giving me 67hz at 1350rpm, which works out nicely to 1200 at 60hz.

Last edited by Stubby79; 03-08-2021 at 11:34 AM..

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 03-09-2021, 01:11 PM #42 (permalink) Somewhat crazed     Join Date: Sep 2013 Location: 1826 miles WSW of Normal Posts: 1,772 Thanks: 176 Thanked 492 Times in 420 Posts I love it when I say goofy things that make people do their own research
 03-09-2021, 01:59 PM #43 (permalink) Master EcoModder     Join Date: Sep 2012 Location: Victoria, BC Posts: 1,714 Firefly EV - '98 Pontiac Firefly EV 90 day: 107.65 mpg (US) Little Boy Blue - '05 Toyota Echo 90 day: 33.35 mpg (US) BlueZ - '19 Nissan 370Z Sport 90 day: 17.19 mpg (US) Thanks: 72 Thanked 551 Times in 413 Posts ARRG! I want that 30 seconds of my life back, you crook!
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