EV Digest 6839
Topics covered in this issue include:
1) RE: How Controllers Make "free" amps (was: 95 BMW 525i conversion)
by "Myles Twete" <[EMAIL PROTECTED]>
2) Re: Multi-million-dollar X Prize set for automotive innovation
by "jerryd" <[EMAIL PROTECTED]>
3) Re: 95 BMW 525i conversion
by Tehben Dean <[EMAIL PROTECTED]>
4) Re: Car Trailer Rental
by Joseph Lado <[EMAIL PROTECTED]>
5) Car Trailer Rental, AND Power of DC.
by "Bob Rice" <[EMAIL PROTECTED]>
6) Power of DC News - Saturday
by Chip Gribben <[EMAIL PROTECTED]>
7) Re: 95 BMW 525i conversion
by Tehben Dean <[EMAIL PROTECTED]>
8) Re: To Charge or not to charge
by "Chuck Hursch" <[EMAIL PROTECTED]>
9) Re: Still the plasma King, a Siamese8 update
by "Chuck Hursch" <[EMAIL PROTECTED]>
10) Re: Still the plasma King, a Siamese8 update
by MIKE WILLMON <[EMAIL PROTECTED]>
11) RE: 95 BMW 525i conversion
by "Dale Ulan" <[EMAIL PROTECTED]>
12) Re: To Charge or not to charge
by [EMAIL PROTECTED]
13) Power of DC - AutoCross
by Chip Gribben <[EMAIL PROTECTED]>
14) Re: 95 BMW 525i conversion
by Paul <[EMAIL PROTECTED]>
--- Begin Message ---
And this is one key selling point of a modern electronic controller versus a
contactor controller.
The contactor controller can only deliver the higher current levels safely
by splitting and paralleling the batteries in the pack.
-MT
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of (-Phil-)
Sent: Monday, June 04, 2007 10:58 AM
To: ev@listproc.sjsu.edu
Subject: How Controllers Make "free" amps (was: 95 BMW 525i conversion)
This is because the controller is acting as a "buck converter". If the
controller is running at half throttle, then the battery volts is halved,
but the amps can be doubled. Lets say the Battery voltage is 100v. (yes
we are assuming no voltage sag, and a perfect world) The Motor is seeing an
average of 50v, so it can suck 200a and the battery average draw will only
be 100a. Do the math: Motor power: 50v * 100a = 5kw and Battery Power
out: 100v * 50a = 5kw.
See, You aren't really getting something for nothing. Free as in Mortgage
not beer!
Again, for anyone trying to understand a PWM motor controller, I suggest
taking a little time to peruse 4QD's site:
http://4qd.co.uk/faq/index.html
-Phil
----- Original Message -----
From: "Dan Frederiksen" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Monday, June 04, 2007 8:00 AM
Subject: Re: 95 BMW 525i conversion
> John Wayland wrote:
>> With the Zilla Z1K adjusted to limit the battery pack max current to 500
>> amps but set to deliver a full 1000 amps to the motor
> is that possible? how does it achieve that?
>
>
--- End Message ---
--- Begin Message ---
Hi Lee and All,
----- Original Message Follows -----
From: Lee Hart <[EMAIL PROTECTED]>
To: ev@listproc.sjsu.edu
Subject: Re: Multi-million-dollar X Prize set for automotive
innovation
Date: Mon, 04 Jun 2007 09:52:31 -0500
>Evan Tuer wrote:
>> Just coming back to this AXP thing, does anyone know if
>> an EV manufacturer or designer is putting something
>> forward for this? The registration is starting soon. It
>> would be good publicity.
>http://auto.xprize.org/xprize/guidelines.html
>
>It's a wonderful idea. However, as someone who is working
>on a production EV, the rules don't make it very
>attractive.
>
>There are substantial entry fees,
That's being looked at for low budget teams, grants
for those fees, help with paperwork.
and documentation
>requirements that will require a staff of people to
>prepare.
They require a detailed business plan which one
should have anyway if one is going into production.
Cars produced to compete will certainly have to
>be specially built and prepared for just this event to
>have any chance of winning.
It looks like the Alt catagory rules were written
for the Freedom EV.
That means big money (the
>winner is the one that spends the most)! For a small
>company, that means diverting scarce resources just to win
>this one event, and that detracts from the company's real
>mission.
If it actually is to encouage production as they say,
those spending the least almost should win as production,
sales price is a big factor in winning. I want to see them
get anywhere near my costs. Their gagetitis, engineers,
trying to justify themselves will defeat themselves as usual
in the big companies.
So far the Tesla, Phoenix, ect can't get 100mpg from
average US grid sources energy equivilent I'd bet. I'll be
close even with 1/2 the weight and less aero, rolling drag.
So they will need serious changes to compete or different
vehicles.
>
>It's set up to produce expensive race cars; not economical
>daily drivers. Requirements like 100 mph top speed,
>scoring based on standings in closed-track racing, sponsor
>logos plastered all over the cars, etc.
I can live with that and bet in a prepared lead
Freedom EV, keep in the running if not win at 1/4 their
costs. It may take a Zilla and twin 8's but I can handle it.
And a Sunrise with your suspension which has many
race parts available, a
White Zombi EV drive, should do well racing at high speeds,
low power. Your body/chassis can be a fair amount lighter,
stiffer than any others there so far including the Telsa
along with it's excellent aero, if the race is based on
energy used, the Sunrise can win against the company
products mentioned. I'm sure the list would help the racing
set up, ect. But I can see you don't want to so I'll drop
it.
Though if anyone else wants to do a 3 or 4wheel EV
for the contest, I'll help with composites, 3wh design, ect.
>
>Notice that the board of directors are all the people that
>you would expect to enter the race themselves; Tesla,
>Phoenix, etc. They are naturally going to make rules that
>favor their own entries winning. So it looks to me more
>like a media event than a serious attempt to attract
>"outsiders". --
We'll see. So far I think it's legit when I talked
to them. They seemed to be doing it to reduce US oil use for
energy independence, national economic, security reasons and
stop wars over oil, at least by us.
No matter what, I'll be the underdog so if I beat
anyone will be worth it for the publicity, which is what
they say it's for, getting funding, interest in eff
vehicles.
Jerry Dycus
>>--
>Lee A. Hart, 814 8th Ave N, Sartell MN 56377,
>leeahart_at_earthlink.net
>
--- End Message ---
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From: Paul <[EMAIL PROTECTED]>
Subject: Re: 95 BMW 525i conversion
Date: Mon, 4 Jun 2007 15:23:27 -0700
To: ev@listproc.sjsu.edu
On Jun 4, 2007, at 12:25 PM, Tehben Dean wrote:
> On Jun 4, 2007, at 6:50 AM, John Wayland wrote:
>
>> Max torque will be about half that of the DC system, so even with
>> the full 68 kw system the 0-60 will be a lot slower, hill climbing
>> will be more arduous.
>
> So are you saying that with a 300v AC system you still won't get
> the performance of a 144v DC system?
I'm more a fan of the idea that power is power. The AC system will
have less torque so to match the initial launch of a 9 inch and Zilla
with the AC system you will have to take off in first gear. With the
DC setup you generally take off in second gear because the motor will
come out of current limit at around 3500 rpm but have huge torque at
low rpms (generally only with low power DC systems is first gear
regularly used.)
The point is, if 2 systems you have the same power its a matter of
gearing to make both of them show the same torque and rpm. AC systems
tend toward higher rpm/ less torque to make power. Series DC systems
tend toward lower rpm/ more torque to make the same power.
Paul "neon" G.
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