View Single Post
Old 11-23-2008, 05:25 PM   #8 (permalink)
captainslug
Misanthropologist
 
captainslug's Avatar
 
Join Date: Sep 2008
Location: Sterling, VA
Posts: 383

BORK! - '89 Volvo 240 DL Wagon
90 day: 21.27 mpg (US)
Thanks: 2
Thanked 24 Times in 13 Posts
Quote:
Originally Posted by americasfuture2k View Post
i dont really remember this exactly, but for a motor to create current, doesnt it need to spin in reverse?
No.
The ability to apply or draw current is dependent upon the control circuitry. Using the motor as a brake is very easy to do, but being able to efficiently use that energy to recharge the batteries is not as simple.
I have an electric scooter that use the drive motor as a brake, but the controller is so cheap and simplistic that all it can do is dump that drawn energy as heat.

When you draw current from a moving motor the energy absorbed will try to decelerate the shaft. The opposite is true when current is applied.

You're confused about what an alternator does. It's converting applied mechanical energy into electrical energy. To do so it has to actually absorb some of the output of the engine, and therefore it's sapping some of the horsepower away from the energy it would otherwise be using to drive the wheels.
You can't create something from nothing.

Last edited by captainslug; 11-23-2008 at 05:41 PM..
  Reply With Quote