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  #21  
Old 03-02-2012, 11:35 AM
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Default Re: Why are DC motor modifications so costly?

It was inspired by my Z4 conversion.
Maybe you know that K11" 250V only handles 210A continuous at 250V.
This was irritating me a lot so we made this motor that is something like 50-53kW/230V/5600rpm/90Nm continuous. For overload purposes one can use a 250-288V battery so rpm stay high under overload conditions.

I was also unhappy with the standard shaft mounted fans as ventilation was rpm dependent. I.E. if you have 1/3 of nominal rpm, your ventilation is like 3 times weaker. Further the standard fans tend to make lots of whining noise at 4000+ rpm. So we re-introduced the specially shaped back flange that you see on the picture to allow forced air cooling to pump more air through the motor.

As this back flange makes it impossible to use it for mounting, we added machined platforms with threads in the motor case so one can hang the motor on those - there are 4 platforms/8 threads in total.

The motor can also come with an SKF sensor bearing producing 80 pulses per revolution - it is automotive class (used in car ABS systems) and is extremely reliable and maintenance free (unfortunately Soliton/Zilla cannot read it ).
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Last edited by Plamenator; 03-02-2012 at 11:32 PM.
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  #22  
Old 03-02-2012, 12:00 PM
Batterypoweredtoad Batterypoweredtoad is offline
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Default Re: Why are DC motor modifications so costly?

Planetmotor-can you post more info about this motor in its own thread or maybe on this one: http://www.diyelectriccar.com/forums...d=1#post288288

I am really curious about it. Will it handle 1000Amps for any length of time? Do you have the motor performance graphs? Etc...
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  #23  
Old 03-02-2012, 12:13 PM
somanywelps somanywelps is offline
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Default Re: Why are DC motor modifications so costly?

Quote:
Originally Posted by Plamenator View Post
It was inspired by my Z4 conversion.
I thought you were doing something using AC?
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  #24  
Old 03-03-2012, 01:08 AM
Duncan Duncan is offline
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Default Re: Why are DC motor modifications so costly?

Quote:
Originally Posted by somanywelps View Post
Understood, my car is nothing more than a parts list at this point

Primary objective is to make sure I don't wind up blowing up something.
As opposed to my philosophy of expecting to blow things up and then replace them with stronger ones
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  #25  
Old 03-03-2012, 03:43 AM
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Default Re: Why are DC motor modifications so costly?

Quote:
Originally Posted by Batterypoweredtoad View Post
Planetmotor-can you post more info about this motor in its own thread or maybe on this one: http://www.diyelectriccar.com/forums...d=1#post288288

I am really curious about it. Will it handle 1000Amps for any length of time? Do you have the motor performance graphs? Etc...
No performance graphs for the moment as I am still wondering how to market it. I.E. be realistic or adopt the methods of our competition and claim a ridiculous figure like 288-300V
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  #26  
Old 03-03-2012, 03:49 AM
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Default Re: Why are DC motor modifications so costly?

Quote:
Originally Posted by somanywelps View Post
I thought you were doing something using AC?
I wanted to use a dual AC motor at the beginning. Like 2 of those:
http://kostov-motors.com/tractionmot...controllerkit/

But the 1238R is very limiting with its 650A/96VDC.
A dual motor would have been only 100kW peak and I wanted 150kW so opted for Soliton1+K11" 250V.

Funny enough but finally I ended up with 90kW peak as the 90Ah Winston cells I chose only give me 500A peak
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  #27  
Old 03-03-2012, 06:38 AM
Batterypoweredtoad Batterypoweredtoad is offline
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Default Re: Why are DC motor modifications so costly?

Quote:
Originally Posted by Plamenator View Post
No performance graphs for the moment as I am still wondering how to market it. I.E. be realistic or adopt the methods of our competition and claim a ridiculous figure like 288-300V
I like how you do it in your "Why Interpoles" explanation on your website. I would love to see a continuous rating (S60?) and then lower time limits all the way down to 1 minute rating with heat gain for each.
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  #28  
Old 03-03-2012, 10:01 AM
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Default Re: Why are DC motor modifications so costly?

Our dyno is high voltage but only goes to 600A.
60min is 260A while 500A are 4min.
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  #29  
Old 03-03-2012, 10:58 AM
efan efan is offline
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Default Re: Why are DC motor modifications so costly?

Quote:
Originally Posted by Plamenator View Post
I wanted to use a dual AC motor at the beginning. Like 2 of those:
http://kostov-motors.com/tractionmotors/kostovevmotors(ac-dc)/3-phaseacmotorsforelectricvehicles/10ac9motor-controllerkit/

But the 1238R is very limiting with its 650A/96VDC.
A dual motor would have been only 100kW peak and I wanted 150kW so opted for Soliton1+K11" 250V.

Funny enough but finally I ended up with 90kW peak as the 90Ah Winston cells I chose only give me 500A peak
this is a bit off topic, but I wanted to see if Plamenator could enlighten us on the pricing of the low power AC systems that are available to the diy community.
I realize that the AC package offered by Kostov motors is at a better price and I am sure equivalent quality to the HPCG AC-50...and I give you credit for that. But for ~$3600 one can purchase a Soliton jr and K9" -220v motor for much better performance.
So why is the AC system at half the power (or worse) of the DC so costly? is the controller the expensive component? or is the motor more complex and costly to produce compared to a DC one? at this price we are looking at $12,000 for 150kw package...not much better than a UQM or AC Propulsion System.
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  #30  
Old 03-03-2012, 05:34 PM
somanywelps somanywelps is offline
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Default Re: Why are DC motor modifications so costly?

Quote:
Originally Posted by Batterypoweredtoad View Post
I like how you do it in your "Why Interpoles" explanation on your website. I would love to see a continuous rating (S60?) and then lower time limits all the way down to 1 minute rating with heat gain for each.
This would be infinitely useful.
Quote:
Originally Posted by Plamenator View Post
I wanted to use a dual AC motor at the beginning. Like 2 of those:
http://kostov-motors.com/tractionmot...controllerkit/

But the 1238R is very limiting with its 650A/96VDC.
A dual motor would have been only 100kW peak and I wanted 150kW so opted for Soliton1+K11" 250V.

Funny enough but finally I ended up with 90kW peak as the 90Ah Winston cells I chose only give me 500A peak
Is that peak a limit of the controller or the motor (or both)?

Would something like this be more appropriate?: http://www.tritium.com.au/products/TRI74/index.html
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