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Re: [EVDL] "Compression" slowing force with electric motors?

Hello Martin,

Every day, when I was coming home from my work place which is located about
600 feet higher than my home and about 5 miles away, I let the EV coast all
the way home from the top entrance of the hill.

The hill is a steep average 7% grade with some areas that are greater than
that which is about 2 miles long which I get up to 80 mph. At the end of
the 2 mile drop, there is about a 2 mile slight down hill that descends down
another 200 feet to a exit which is a slight up hill and I am still doing 50
mph at the entrance of the exit and slow down to 35 mph at the end of the

I then start to descend down another hill which the EV is now up to 45 mph
and then go up another hill that is not as high and down again. Like a
roller coaster.

I then make a left and start to descend down another hill for four blocks at
about a speed of 20 mph and then click the garage door opener and turn left
into my garage which is a slight up ramp and only the apply the brakes in
the garage.

With no mechanical regen, my EV can coast about 5 miles which feels just
like a ICE on cruise control.

Now going up the hill is another matter. I do not take the same route going
up the hill. From my home, I have to travel up hill about four blocks, but
instead of turning right on the road that I come down on the hill, I turn
left and continue to coast down for a half mile turning left which is a
level driving for about 5 blocks.

To ascended this hill, I then turn right which is down hill run for about a
mile and accelerated to up 70 mph which I can roller coast the hill for
about 3/4 mile which I then exit where the exit speed is 35 mph, I am still
going about 45 mph and I only have to apply power for about 1000 feet of
exit road.

The EV I was using was a proto type call Transformer I which had 180 volt
battery pack that was rated at 300 AH. It had special Good Year tires that
had a high roll out rate. I later install radial Dunlaps and those were the
worst tires I had even though there were 65 pxi at 2350 load rating. The
radials back in 85 had too much deflection and the EV would actually slow
down on this hill like I had a compression engine in it.


----- Original Message -----
From: "Martin Maitner" <xxx[email protected]>
To: <[email protected]>
Sent: Wednesday, August 29, 2007 7:39 PM
Subject: [EVDL] "Compression" slowing force with electric motors?

> Hello to everybody. This is my first post to the forum. I was thinking
> today how you can use engine compression and the force of gravity to slow
> an ICE vehicle while coasting rather than riding the brakes all the time.
> I wonder what it feels like to coast in an EV? Do you get any
> "compression" effect from the electric motor or is gravity the only force
> slowing the speed? Keep in mind I am just talking about a motor that
> propels the car, not one with regenerative braking capability. I am all
> too familiar with regenerative braking with my 2000 Honda Insight. I can't
> get used to how fast it slows you down without even applying the brakes. I
> preffer to start coasting much farther away than I am permitted because of
> the regenerative braking!
> ~Marty
> _______________________________________________
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