# where to get a good ac motor?



## frodus (Apr 12, 2008)

whats it for, thats the first question.


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## Microamp (Mar 8, 2010)

ok i'm planning to convert a toyota 4x4 (not sure what model!) but if i cant get hold of that one then i will be looking for some other gas monster to rehabilitate


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## Jan (Oct 5, 2009)

6.7 kW is less than 10 BHP. Maybe that will give you an idea?


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## Microamp (Mar 8, 2010)

Jan said:


> 6.7 kW is less than 10 BHP. Maybe that will give you an idea?


so, what would be a normal input for an ac motor?


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## Jan (Oct 5, 2009)

Microamp said:


> so, what would be a normal input for an ac motor?


That's not the issue. Have you any idea how many bhp a regular 4x4 has?


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## corbin (Apr 6, 2010)

Microamp said:


> where can i find a good ac motor?
> 
> (i thought a site like this might have a sticky with links for this kind of Q!)
> 
> ...


Hi Microamp,
I did an analysis of what is on the market not too long ago.

http://www.corbinstreehouse.com/blog/2010/04/plug-bug-ev-ac-drive-motor-controller-selection/

corbin


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## kaiseraw (Aug 11, 2010)

Have you found an AC motor for your project yet? If not, I have a new Azure Dynamics AC-90 motor and DMOC-645 Inverter for sale. Let me know if you are interested.


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## Microamp (Mar 8, 2010)

Hi, no i dont have the moteor yet, i'm just looking at the options, while i concentrate on getting the power system working. but thanks for the offer though, i'll certainly check out the details of that motor and see if it is still available closer to when i need it


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## tomofreno (Mar 3, 2009)

The conversion factor is approximately 746 W/horsepower. Google the specs for the 4x4 of your choice to see what horsepower the engine has, convert to kW to get an idea what motor might be appropriate. Torque is very important too, so look at that in the specs while you are there. Then look at Corbin's list to compare. Then do a lot more study/research, then questioning, before you buy anything.


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## JRoque (Mar 9, 2010)

Hey Tom, did you mean 746 Watts = 1 HP?

I'm not sure if this motor's 78kW rating is peak or sustained but at $7K, it might be the latter. 78kW = 105HP, not too bad. It does include the controller for that price so it's not unreasonably priced. Anyone know that motor?

JR


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## samborambo (Aug 27, 2008)

Microamp said:


> where can i find a good ac motor?
> 
> (i thought a site like this might have a sticky with links for this kind of Q!)
> 
> ...


I think everyone else is missing the point here. You already have a 6.5kVA inverter for a 400VAC motor. That's a start. If you're planning on converting a Toyota Hilux, google "a4x4kiwi electrolux". Mal did an AC induction motor conversion on a Hilux with a 160 or 180 frame motor.

As it has already been pointed out, 6.5kVA is not a lot of power but it could be made into a lot of torque. If you just want a 4x4 vehicle for off-road limited to 20mph then this set up may suit you fine. At least you'll learn a lot from a low power conversion.

Your battery pack is at least 620VDC with a max current draw of 15A for a 400VAC inverter and motor. That's sqr2 x 400VAC (the peak of RMS) plus a little extra for switching volt drop and battery internal resistance volt drop.

In three phase circuits there is a sqr3 relationship between the motor current, voltage and power. That is P = V x I x 1.73

Your inverter needs to be modified to bring out the DC bus for connection to the batteries. Also, your inverter needs to be capable for torque control rather than speed control.

Back to the motor. A standard 3p 5.5kW industrial AC induction motor will do the job. Aluminium frame motors are lighter but that's less important in your case. If you want to feed directly into the transfer case a 4 pole motor should be suitable for low ratio.

Good luck.

Sam.


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## tomofreno (Mar 3, 2009)

> Hey Tom, did you mean 746 Watts = 1 HP?


 Yes. Thanks. I edited the original.
That motor looks interesting, but there seems to be no info on it.


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## Microamp (Mar 8, 2010)

Thanks for all the info guys, you've given me a good place to start. i'll hope fully be getting enough components together soon to start the build so i'll keep you upto date! any other info on this topic is welcome!


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## Bowser330 (Jun 15, 2008)

I vote you sell your 6kw inverter for whatever you can get for it, and buy this....
http://currentevtech.com/Drive-Syst...ers/120KW-BLDC-Motor-and-Controller-p168.html

120kw peak, 161hp @ 460ftlbs, can rev to 5000rpm (similar profile to a diesel engine but with more torque earlier in the powerband)


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## JRoque (Mar 9, 2010)

> 120kw peak, 161hp @ 460ftlbs, can rev to 5000rpm


oh..ohh.ohh..ahh.... anybody got a tissue? 

Seriously, that's a monster motor... with a price tag that goes along with it. But did you see the other motors on Dave's page? Nice selection, good for him.

JR


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