[ausev] good motor generator

[Chris Robison]

m. edmund howse wrote:
> http://cgi.ebay.com/NEW-10-HP-8700W-DC-WIND-GENERATOR-MOTOR_W0QQitemZ230256987038QQihZ013QQcategoryZ42922QQssPageNameZWDVWQQrdZ1QQcmdZViewItem 

Even if you could install it (the motor pictured is over 2 feet long) 
this actually would be a poor choice for use in an EV, due to its low 
power density (most likely from the weight of the permanent field 
magnets, plus its apparently limited ventilation).  It's rated at 10HP; 
we'll assume that's continuous and not peak. It weighs somewhere close 
to 170lbs.

In comparison, the 6.7" Advanced DC X91-4001 is also rated at 10HP 
continuous, and weighs less than 90lbs. Or looking at it the other way, 
a big 9" Advanced DC motor (FB1-4001) weighs 143lbs, and is rated at 
28HP continuous.

Also, if you want regenerative braking you'll need a controller that's 
designed to be used with a permanent magnet motor, and you won't find 
those off-the-shelf for full-size EVs.

The difficulty of regenerative braking is an unfortunate downside to 
series-wound motors, but there are enough advantages to them 
(combination of high starting torque and smooth acceleration to high 
RPM) that you'll be basically on your own if you decide to go with 
shunt-wound or permag in a highway-speed 4-wheel vehicle.

   --chris