Starting new build: BMW 3-series (E46) - high-performance electric - Page 2 - DIY Electric Car Forums
Go Back  

DIY Electric Car Forums > EV Conversions and Builds > All EV Conversions and Builds

Register Blogs FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #11  
Old 06-15-2011, 02:57 PM
Bowser330 Bowser330 is offline
Senior Member
 
Join Date: Jun 2008
Posts: 1,682
Bowser330 is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Quote:
Originally Posted by Yabert View Post
Hey! be careful.

You don't have enough battery power because your voltage is too low!

800 x 0.0009 = 0.72 - 3.2 = 2.5v x 90 = 225v.
800A x 225v = 180Kw from cells and roughly 200 hp at motor shaft....... so, not enought!

You probably need at least 250 hp....
The conversion from kw to hp seems low in your calculation....

180kw / 0.745 = 242hp
Reply With Quote
Sponsored Links
Advertisement
 
  #12  
Old 06-15-2011, 03:50 PM
valerun valerun is offline
Senior Member
 
Join Date: Nov 2010
Posts: 1,420
Blog Entries: 1
valerun is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Quote:
Originally Posted by Bowser330 View Post
The conversion from kw to hp seems low in your calculation....

180kw / 0.745 = 242hp
I think Y meant mechanical hp - after taking into account ~80% motor & drivetrain efficiency...
Reply With Quote
  #13  
Old 06-27-2011, 12:33 AM
valerun valerun is offline
Senior Member
 
Join Date: Nov 2010
Posts: 1,420
Blog Entries: 1
valerun is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Hi Guys,

still musing over the details of this conversion.

Narrowing down the DC motor choice to Warp11HV mated with 340V CALB pack. It just have to have a big DC motor to provide the power we need.

However, we are going to do some long-range demo drives in this car and every bit of efficiency counts so I was thinking of adding something like an AC50 system to the big DC motor. AC50 would then soak up braking / downhill and provide most of the 'baseline' load on freeway etc. Being AC and therefore more efficient, it should further add to the economy.

What do you guys think? Has anyone done it before? Any links / pointers?

Thanks,
Valery.
Reply With Quote
  #14  
Old 06-27-2011, 12:53 AM
DavidDymaxion DavidDymaxion is offline
Senior Member
 
Join Date: Dec 2008
Posts: 1,348
DavidDymaxion is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Several of the 914 ev guys use ACXX motors, you could do a search at http://groups.google.com/group/914ev .
Quote:
Originally Posted by valerun View Post
Hi Guys,

still musing over the details of this conversion.

Narrowing down the DC motor choice to Warp11HV mated with 340V CALB pack. It just have to have a big DC motor to provide the power we need.

However, we are going to do some long-range demo drives in this car and every bit of efficiency counts so I was thinking of adding something like an AC50 system to the big DC motor. AC50 would then soak up braking / downhill and provide most of the 'baseline' load on freeway etc. Being AC and therefore more efficient, it should further add to the economy.

What do you guys think? Has anyone done it before? Any links / pointers?

Thanks,
Valery.
__________________
Reply With Quote
  #15  
Old 06-27-2011, 01:11 AM
valerun valerun is offline
Senior Member
 
Join Date: Nov 2010
Posts: 1,420
Blog Entries: 1
valerun is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Quote:
Originally Posted by DavidDymaxion View Post
Several of the 914 ev guys use ACXX motors, you could do a search at http://groups.google.com/group/914ev .
Thanks David. Do you know if anyone did it in a DC-AC hybrid mode, though? AC50 by itself will barely make a 3500lbs BMW move (well, in my frame of reference, anyway ;-)
Reply With Quote
  #16  
Old 06-28-2011, 05:30 AM
Yabert's Avatar
Yabert Yabert is offline
Senior Member
 
Join Date: Feb 2010
Location: Québec, Canada
Posts: 1,071
Yabert is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Do you only compare the coplete efficiency of the AC50 vs WarpHV????

DC = 99% controller efficiency x 87-88% motor = 87% efficient than seem good to me....

What about AC50?.... 94% x 92% = 87%???????

My final advice: Put a bit more cells. They costing less and they weighting less than an AC50 systems!!
__________________
My Smart Fortwo high power! 38 000+ EV Km
http://www.diyelectriccar.com/forums...ion-51472.html
Reply With Quote
  #17  
Old 06-28-2011, 09:15 AM
valerun valerun is offline
Senior Member
 
Join Date: Nov 2010
Posts: 1,420
Blog Entries: 1
valerun is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Quote:
Originally Posted by Yabert View Post
My final advice: Put a bit more cells. They costing less and they weighting less than an AC50 systems!!
good point. 150lbs of cells are ~20 miles of range, after all...
Reply With Quote
  #18  
Old 06-30-2011, 11:05 AM
Bowser330 Bowser330 is offline
Senior Member
 
Join Date: Jun 2008
Posts: 1,682
Bowser330 is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Quote:
Originally Posted by valerun View Post
good point. 150lbs of cells are ~20 miles of range, after all...
90 Calb 100AH cells (288V nom * 100AH = 28.8kw)

you will definitely not be needing more than 28kwh to achieve 100 mile range @ city speeds...

http://www.evconsultinginc.com/artic...dc_system.html

The article above points out that the average car only needs 5kw to cruise @ 40mph (city speeds). So a 100 mile distance @ 40mph requires 12.5kwh
Reply With Quote
  #19  
Old 07-04-2011, 03:15 AM
valerun valerun is offline
Senior Member
 
Join Date: Nov 2010
Posts: 1,420
Blog Entries: 1
valerun is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

Quote:
Originally Posted by Bowser330 View Post
http://www.evconsultinginc.com/artic...dc_system.html

The article above points out that the average car only needs 5kw to cruise @ 40mph (city speeds). So a 100 mile distance @ 40mph requires 12.5kwh
Hi Bowser,

this would be awesome. However, I think these guys either missing some power loss contributions or talking about purely mechanical power or using really streamlined / lightweight car example or all of the above. I've used Formulas from the book 'Build your own electric car' before and am coming out at 27hp required for a 3500lb BMW to move at 60mph (as opposed to 15hp that these guys quote). My calculation gives me ~330 Wh/mile which is in the right ballpark for 60 mph.

This gets me the range of just shy of 100 miles at 60 mph. At 40 mph, it's 140 miles or 40% higher.

V
Reply With Quote
  #20  
Old 07-08-2011, 04:46 PM
valerun valerun is offline
Senior Member
 
Join Date: Nov 2010
Posts: 1,420
Blog Entries: 1
valerun is on a distinguished road
Default Re: Starting new build: BMW 3-series (E46) - high-performance electric

ok guys! FINALLY some good stuff to look at ;-)

$1K in the friendly shop gives you an EV-ready beemer! Engine, radiator, gas tank and exhaust systems are out

design work is starting today. Everything in CAD to be replicable for our E46 kits.

V
Attached Images
File Type: jpg DSC_6505.jpg (100.9 KB, 77 views)
File Type: jpg DSC_6507.jpg (87.9 KB, 62 views)
Reply With Quote
Reply

Share or Bookmark this

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

 
Support DIY Electric Car
Sponsors

All times are GMT -6. The time now is 11:35 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Ad Management by RedTyger