Re: Brakes - EV1

[Dave Goldstein <goldie.ev1@juno.com>]

On Tue, 29 Jan 2002 16:49:45 -0500 (EST) Mike Thompson <mikt@pair.com>
writes:
> The EV1 solution doesn't require thought.
> 
> Leave the coast down button in and when you release the 
> accelerator it slows like compression braking in an ICE, 
> It's comparable in strength to ICE compression braking 
> depending on which gear, speed, etc of the ICE.
> 
> Need more braking? apply the brakes lightly and the car 
> regens stronger.  As you depress the brake farther, 
> mechanical brakes join the braking process.


   I agree fully with Mike.  The EV1 regen system -- 
especially the improved version on the Generation 2 
EV1 -- is among the best in the business!  It is 
smooth, progressive, user-transparent and highly 
effective, both in hauling the 2900 pound (1,300 kg) 
car down very quickly and in recovering brake 
energy that would otherwise be lost as heat.

  Two notable examples:  

  (1)  I drove a rented NiMH-powered EV1 from 
LAX (Los Angeles Airport) 25 miles (40 Km) up 
the coast through stop-and-go traffic to Topanga 
Canyon Boulevard in Malibu -- and arrived with 
the *same* "Miles Remaining" figure (87 miles / 
140 Km) showing on the digital fuel gauge as 
when I first started out!  (Yes, part of this was 
the range calculator adjusting to my smoother 
driving style compared to the previous driver.  
But having driven an earlier Gen 1 EV1 on the 
same route, I had expected to *lose* about 20 
miles (32 Km).  The only difference this time, 
was the newer car and my liberal use of the 
*coast down button* on the side of the console 
shift lever.
  
  (2)  Another NiMH (Gen 2) EV1 run from Thousand
Oaks, CA to Ventura, CA on the 101, three weeks 
ago.  Mostly hilly freeway driving (70+ mph / 115 Kmh) 
with some abrupt slowdowns for traffic congestion.  
Fifteen miles down the freeway, I had 10 *more* 
miles (16 Km) showing on the "Miles Remaining"
indicator than when I started out!   (And yes, I have 
found the "Miles Remaining" gauge to be quite 
accurate.)  Favorable terrain (more downhill than 
up?) may well have been a factor, but even so, 
that is an *amazing* amount of recovered energy, 
and the brakes were always capable and easy to 
modulate.

  I have not driven a tZero, so I cannot compare the
regen.  But all I can say is, "Driving is believing!"
If you don't believe me, I urge you to rent an EV1
from EV Rentals at LAX or Burbank Airport -- before
they all disappear -- and try this for yourself.

    Regards,

    Dave Goldstein
    President, EVA/DC and
    Program Development Associates
    Gaithersburg, MD  USA
    
---


> 
> On Tue, 29 Jan 2002 ScuderiaEV@aol.com wrote:
> 
> > In a message dated 28/01/02 21:29:17 GMT Standard Time, 
> vtikhono@lsil.com
> > writes:
> >
> > > With regen capable drive I'd say regen braking is your *main* 
> braking
> > >  means and the disk brakes are used as *aid* (for complete 
> stops),
> > >  not the other way around.
> >
> > Depends on whether you ever engage your brain whilst driving. Ask 
> most people
> > what they would do if they wanted to slow down and you only get a 
> very few
> > who'll say "lift off the throttle".
> >
> >
> > Paul Compton
> > www.sciroccoev.co.uk
> >
> >
> 
> Later,          "A rainbow is only part of a circle." San Joser, CA
>      ^ ^        Software Consultants:        
> http://www.migration.com/
>      O o        Permanent:                   m.t.thompson@ieee.org
>   ===-o-===     My catbox:                   http://www.madkatz.com/
> Ack! Phththpph!
> 
> 2001 Clean Air Champion 
> http://www.baaqmd.gov/pie/press/cachamp01.pdf
> 
> True Zero Emission Vehicle (TZEV) GM EV1 and my home powered by
> 100% renewable, Zero emission 30kWh/day Solar Electric (PV) system
> on my roof:  http://www.madkatz.com/pv/index.html
> 
> Sometimes I see gas cars... In my rearview mirror! 
> http://www.gmev.com/
> 
> President, Electric Auto Association, San Jose Chapter
> http://www.geocities.com/sjeaa/
> 
> EV List Archive Owner,Admin  
> http://www.crest.org/discussion/ev/current/
> Electric Vehicle Email List Instructions: (EVList members: Bookmark 
> it!)
> http://www.madkatz.com/ev/evlist.html
>