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Discussion Starter · #1 ·
I’m trying to do my first ev build on a Geo Metro I recently got. I ran into a industrial motor for cheep. here are the specs.
122697

I was impressed by the hp rating but it is super heavy and the amount of amps and rpms seem really low to me. My goal is to reach at least 55mph. I’m just getting into ev builds so I don’t know if this will work. Can I use this motor for my build?
 

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It’s 3 phase so theoretically yes you could use it for some sort of EV

That said I highly doubt it’s useful enough to drive a Geo Metro 55 mph

It’s rated RPM and power curves + continuous rating really aren’t what you need in an over the road car
 

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The rated speed is a direct result of the drive frequency, which is 60 Hz because that's what utility AC power is. It could certainly be driven much faster, but of course there is no indication of how well it would work (electrically), or what speed it can stand (mechanically). To some point, it might be able the same current (and thus produce the same torque if appropriately controlled) at higher speed, thus producing more power, and you would need to do that to make it a practical EV motor; however, there are two issues:
  1. the maximum current at higher speed is unknown
  2. significantly higher speed would require significantly higher voltage

The "AC-" motors from HPEVs are typical industrial induction motors vaguely like this, but wound for much lower voltage operation.
 

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I’m trying to do my first ev build on a Geo Metro I recently got. I ran into a industrial motor for cheep. here are the specs.
I was impressed by the hp rating but it is super heavy and the amount of amps and rpms seem really low to me.
My goal is to reach at least 55mph. I’m just getting into ev builds so I don’t know if this will work. Can I use this motor for my build?
Yes if you can
1) Fit it in with the current gearbox/transmission (you would drive it in 3d and 5th gear mostly I would think)
2) Find an inverter that you can adapt to this motor to increase the rpm to at least 2500 RPM in field weakening
3) Keep the total weight of the vehicle under 1300 kg.

This seems to be a 4 pole motor which should give you a decent torque up to 30mph (50 km/h) after that you will struggle a bit to accelerate.
It will do about up to 60 mph under ideal conditions (no hills, no wind, 1 passenger/driver)
You should be able to cruise with 50mph, assuming points 1)-3) are fullfilled
 

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Discussion Starter · #5 ·
Yes if you can
1) Fit it in with the current gearbox/transmission (you would drive it in 3d and 5th gear mostly I would think)
2) Find an inverter that you can adapt to this motor to increase the rpm to at least 2500 RPM in field weakening
3) Keep the total weight of the vehicle under 1300 kg.

This seems to be a 4 pole motor which should give you a decent torque up to 30mph (50 km/h) after that you will struggle a bit to accelerate.
It will do about up to 60 mph under ideal conditions (no hills, no wind, 1 passenger/driver)
You should be able to cruise with 50mph, assuming points 1)-3) are fullfilled
do you have any recommendations on an inexpensive inverter that would work? What kind of voltage should I run it at?
 

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do you have any recommendations on an inexpensive inverter that would work? What kind of voltage should I run it at?
I would suggest that you contact Johannes Huebner at openinverter.org, he has done a conversion with an open source inverter and a standard induction motor quite similar to your project, you can find the thread here in the forum and also here Customer Projects - openinverter.org - Open Source AC motor inverter.
Edit: Regarding the voltage I would start with 208-230V, then you can start with a smaller battery pack.
 

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You might consider running it with a VFD. There are a bazillion of them on eBay

Your biggest problem is going to be cooling it. Its cooling system is designed for it to work at rated RPM. At rated HP, it'll want to get rid of a space heater worth of heat (around 1100W).

With 15HP, about 12kW, you're not getting up any hills with that thing at speed - with a gearbox, maybe go up at 15-20mph. For around town, flat, it'd be ok - a double speed golf cart, pretty much
 
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