Re: Braking

["Thomas J Webster" <ford1929@frontiernet.net>]

That would be more efficent then a box of salt water -Tom
----- Original Message -----
From: "Glenn Wittrock" <spamproof@pluggedin.ca>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, January 29, 2002 8:29 AM
Subject: Re: Braking


> Or you could add some supercapacitors to soak up the surge of regen and
then
> dump that surge back in for acceleration.
>
> Thomas J Webster wrote:
>
> > Or you could build a load box, like what they do to exersize diesel
> > locomotives? Tom
> > ----- Original Message -----
> > From: "Bryan Andersen" <bryan@visi.com>
> > To: <ev@listproc.sjsu.edu>
> > Sent: Tuesday, January 29, 2002 12:23 AM
> > Subject: Re: Braking
> >
> > > A possibility I just thought of:
> > >
> > > Why not incorporate a electrical heat dump into the car.  Size
> > > it for the maximum amount of regen braking you can dump into
> > > your batteries.  If the batteries are full, then dump the excess
> > > energy into the electrical heat dump.  This way "regen" braking
> > > is consistent and one can simplify the regen / mechanical braking
> > > distribution.
> > >
> > > A suitable heat dump could be quite similar to an electric heater.
> > > Basically some resistive heating elements with a fan blowing over
> > > them.  Locomotives have been using this method for years.  Note,
> > > you will not want this in your passenger compartment.  One stop
> > > with it fully engaged and you will understand.  Multiple heating
> > > elements each switched separately can provide simple control of
> > > the energy dumped through it.  An issue is how many kilowatts one
> > > can easily dump in a small area.
> > >
> > > As an example, a 2200W 240VAC finned strip heater has an active
> > > finned length of 19" with 2" x 1.375" fins and an overall length
> > > of 23.25".  Smaller and larger sizes are available.  I chose this
> > > size as a single $3 IGBT can switch it easily.  Even placing them
> > > two deep in an array one ends up with a rather significant sized
> > > box if one wanted to dump 200A.  The overall box would end up about
> > > 24" long, 16" wide, and 4" deep + whatever one needs for fans, say
> > > an additional 3".  Maybe not quite practical, but an idea.  The
> > > maximum temperature of the elements is 600F.  If one had suitable
> > > air flow one could easily go deeper than the two deep I used.
> > > Going 4 deep gives a box size of 24"L x 8"W x 11" deep.
> > >
> > > Anyways it's an idea.
> > >
> > > --
> > > |  Bryan Andersen   |   bryan@visi.com   |   http://www.nerdvest.com
|
> > > | Buzzwords are like annoying little flies that deserve to be swatted.
|
> > > |      "Linux, the OS Microsoft doesn't want you to know about.".
|
> > > |   -Bryan Andersen
|
> > >
> > >
>
> --
>
> Glenn Wittrock
>
> Linux: when you need to run like a greased weasel.
>
>
>