EV Digest 6753
Topics covered in this issue include:
1) Re: Field weakening basics - Thank you for the info.
by Steven Ciciora <[EMAIL PROTECTED]>
2) Re: PFC-20
by "TrotFox Greyfoot" <[EMAIL PROTECTED]>
3) More press - PC Magazine
by "Marty Hewes" <[EMAIL PROTECTED]>
4) Re: AGNS bike garners 120volt record
by John Wayland <[EMAIL PROTECTED]>
5) Re: AGNS bike garners 120volt record
by [EMAIL PROTECTED]
6) Re: AGNS bike garners 120 volt record
by Chip Gribben <[EMAIL PROTECTED]>
7) Re: AGNS bike garners 120volt record
by [EMAIL PROTECTED]
8) Re: Doin' the math
by Jeff Shanab <[EMAIL PROTECTED]>
9) PLEASE FIX YOUR EMAIL CLIENTS!
by "Martin Klingensmith" <[EMAIL PROTECTED]>
10) Re: Motor equations
by Jeff Major <[EMAIL PROTECTED]>
11) Re: estimating power using battery internal resistance values
by Lee Hart <[EMAIL PROTECTED]>
12) RE: Motor equations
by Jeff Major <[EMAIL PROTECTED]>
13) Re: PLEASE FIX YOUR EMAIL CLIENTS!
by "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
14) Re: Jinxed! ( Now - Belktronix) LINK
by "Bob Rice" <[EMAIL PROTECTED]>
15) Power of DC Ya goin'?
by "Bob Rice" <[EMAIL PROTECTED]>
16) Re: Power of DC Ya goin'?
by nikki <[EMAIL PROTECTED]>
17) Re: Doin' the math
by Tim Humphrey <[EMAIL PROTECTED]>
18) Goiin' to the Movies WAS Re: PLEASE FIX YOUR EMAIL CLIENTS!
by "Bob Rice" <[EMAIL PROTECTED]>
19) Re: Motor equations
by "Marty Hewes" <[EMAIL PROTECTED]>
--- Begin Message ---
And the additional education wasn't all yours :-)
It's amazing how hearing something described from a
different point of view can increase your
understanding of something you thought you understood.
Thanks as well.
- Steven Ciciora
--- Steve Condie <[EMAIL PROTECTED]> wrote:
> Thanks to all who responded. I am much obliged for
> the the additional education.
>
>
>
>
> ---------------------------------
> Ahhh...imagining that irresistible "new car" smell?
> Check outnew cars at Yahoo! Autos.
____________________________________________________________________________________
Bored stiff? Loosen up...
Download and play hundreds of games for free on Yahoo! Games.
http://games.yahoo.com/games/front
--- End Message ---
--- Begin Message ---
You mean like a rubber grommet? Seems a simpler solution to use
something pre-fabed.
Just a thought...
Trot, the EV-less, fox... (currently that is.)
On 5/10/07, Joe Smalley <[EMAIL PROTECTED]> wrote:
A short piece of hose cut to fit between the pot and the panel should do it.
The screwdriver goes in through the hose and can't touch anything but the
inside of the hose. If it were glued to the front panel, it would go on and
off with the panel.
Joe Smalley
Rural Kitsap County WA
Fiesta 48 volts
NEDRA 48 volt street conversion record holder
[EMAIL PROTECTED]
----- Original Message -----
From: "Jeff Shanab" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List" <ev@listproc.sjsu.edu>
Sent: Wednesday, May 09, 2007 5:13 AM
Subject: Re: PFC-20
> Maybe a plastic shroud fitted over the pot and up against the case would
> be a good long term fix. It is all that freedom that gets us in trouble?
>
> ie
> xxx | | yyyy
> |__|
> -----------||------------ board, x and y hazards
>
>
> ========== =========== case
>
>
>
>
> Added shroud
>
> xxx | | yyyy
> |__|
> ----------||||----------- board, x and y hazards
> | |
> _| |_
> ========== =========== case
--
| /\_/\ TrotFox \ Always remember,
| ( o o ) AKA Landon Solomon \ "There is a
| >\_/< [EMAIL PROTECTED] \ third alternative."
--- End Message ---
--- Begin Message ---
PC Magazine did about a full page overview on the Tesla in their May 22
edition. It's purely an overview, but it's pretty positive. They even
tossed out a cost number of $0.01 per mile if charged off peak. That should
get some attention.
Reminds me of a saying my Dad used to quote, it doesn't matter what you say,
as long as you spell the name right. All press is probably good press, with
statements like Leno's out there with more positive ones like this, it'll
create controversy, which breeds awareness, I hope.
Marty
--- End Message ---
--- Begin Message ---
Hello Shawn and All,
Congrats...again!
[EMAIL PROTECTED] wrote:
Springtime fianllay came to Thompson Raceway....3 new NEDRA records,
One flame job, and one group of addicted EV racers.
Oh stop it! All this talk of flames, arcs, and sparks has got me
salivating to get back to the track.
See Ya.....John 'Plasma Boy' Wayland
--- End Message ---
--- Begin Message ---
I'll send some photos and a video of the last run to Chip today. I just
looked inside those beautiful German motors.
Looks like an acetylene torch was in there. The brushes are gone.
Before they went away they almost blew clear through the armature Maybe
we can make a nice wall clock out of the housings.
Shawn
-----Original Message-----
From: [EMAIL PROTECTED]
To: ev@listproc.sjsu.edu
Sent: Thu, 10 May 2007 8:14 AM
Subject: Re: AGNS bike garners 120volt record
Pictures! We want to see pictures of this new Bike!!
Congrats on the new records, and thanks for showing
everyone how much fun racing can be.
- Steven Ciciora
--- [EMAIL PROTECTED] wrote:
Springtime fianllay came to Thompson Raceway on
Wednesday night with
temps in the mid 70's and light wind.
The Lawless crew and AGNS were there for grudge
night with hopes of a
120 volt record run and 100 mph. Having let work get
in the way of our
racing we didn't get to the track until after 6 pm.
We had just enough
time for 2 runs during T-N-T. First run 13.85 @
92.47. A quick recharge
later and a 13. 78 @ 94.723. They are within 1% so
the second time
should stick as the new 120 volt record.
We were headed in the right direction but since we
were the last TNT
run we didn't have time to recharge before
eliminations began a few
minutes later. I talked to the starter and he agreed
to allow us a
timed run whenever we were ready. What cool folks!
Well you know what
happens when you have too much time to think. Should
we make another
120volt run? Experience with this bike tells me that
it probably would
have been a 13.6? at 95-96 mph. Not bad considering
we were running a
single starnd of 10 Hawkers and 60% less battery
than we had at 96
volts. Should we bump up to 144 volts or go all the
way and see what
192 volts will do? We stuffed 6 more Hawkers in
there and were floating
around 215 volts by the time we were in staging. We
positioned
ourselves at the 600 ft mark and waited. Denis came
down the track like
he was sent from a silent cannon but he must have
wanted to show off
because when he got right in front of us at 600 ft.
the motors put on a
nice light show. Safe to say I now know how high I
can't set the motor
voltage. All kinds of nasty noises accompanied the
sparks and AGNS
snapped, crackled, and popped down the rest of the
track all the way to
a 13.39 @ 93.83. We headed down track to a find
pair of smoldering
Perm motors, a heartbroken Denis that he had done
this to his AGNS and
an otherwise ready to run bike. We'll open up the
motors today. Should
find all kinds of parts to hang on the wall. What a
week of racing! 3
new NEDRA recors, One flame job, and one group of
addicted EV racers.
When will AGNS get 100 mph? Next week at 144 volts I
hope.
Shawn Lawless
________________________________________________________________________
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--- End Message ---
--- Begin Message ---
Hi Steve,
There are pictures on the NEDRA home page.
http://www.nedra.com
Chip Gribben
NEDRA Webmaster
On May 10, 2007, at 8:14 AM, Electric Vehicle Discussion List wrote:
From: Steven Ciciora <[EMAIL PROTECTED]>
Date: May 10, 2007 8:14:02 AM EDT
To: ev@listproc.sjsu.edu
Subject: Re: AGNS bike garners 120volt record
Pictures! We want to see pictures of this new Bike!!
Congrats on the new records, and thanks for showing
everyone how much fun racing can be.
- Steven Ciciora
--- End Message ---
--- Begin Message ---
Hey! Congratulations on your new record(s). So how many times did you
break the record this week?!
Anyway, my condolences to AGNS's motors.
Great stuff!!
Heidi and I are going to the Power of DC this year!!! Yea!
See you there...
Ken
-----Original Message-----
From: [EMAIL PROTECTED]
To: ev@listproc.sjsu.edu
Sent: Thu, 10 May 2007 7:08 AM
Subject: AGNS bike garners 120volt record
Springtime fianllay came to Thompson Raceway on Wednesday night with
temps in the mid 70's and light wind.
The Lawless crew and AGNS were there for grudge night with hopes of a
120 volt record run and 100 mph. Having let work get in the way of our
racing we didn't get to the track until after 6 pm. We had just enough
time for 2 runs during T-N-T. First run 13.85 @ 92.47. A quick recharge
later and a 13. 78 @ 94.723. They are within 1% so the second time
should stick as the new 120 volt record.
We were headed in the right direction but since we were the last TNT
run we didn't have time to recharge before eliminations began a few
minutes later. I talked to the starter and he agreed to allow us a
timed run whenever we were ready. What cool folks! Well you know what
happens when you have too much time to think. Should we make another
120volt run? Experience with this bike tells me that it probably would
have been a 13.6? at 95-96 mph. Not bad considering we were running a
single starnd of 10 Hawkers and 60% less battery than we had at 96
volts. Should we bump up to 144 volts or go all the way and see what
192 volts will do? We stuffed 6 more Hawkers in there and were floating
around 215 volts by the time we were in staging. We positioned
ourselves at the 600 ft mark and waited. Denis came down the track like
he was sent from a silent cannon but he must have wanted to show off
because when he got right in front of us at 600 ft. the motors put on a
nice light show. Safe to say I now know how high I can't set the motor
voltage. All kinds of nasty noises accompanied the sparks and AGNS
snapped, crackled, and popped down the rest of the track all the way to
a 13.39 @ 93.83. We headed down track to a find pair of smoldering Perm
motors, a heartbroken Denis that he had done this to his AGNS and an
otherwise ready to run bike. We'll open up the motors today. Should
find all kinds of parts to hang on the wall. What a week of racing! 3
new NEDRA recors, One flame job, and one group of addicted EV racers.
When will AGNS get 100 mph? Next week at 144 volts I hope.
Shawn Lawless
________________________________________________________________________
AOL now offers free email to everyone. Find out more about what's free
from AOL at AOL.com.
________________________________________________________________________
AOL now offers free email to everyone. Find out more about what's free
from AOL at AOL.com.
--- End Message ---
--- Begin Message ---
huh? You made me check and I can't even get close to your differences
But I think your choice of 50Kwh is amplifing the cost difference ,
ignoring or not taking advantage of the weight difference.
First it is a lofty goal, 50kwh/250wh/mile is 200 miles range. but with
over 5000lbs of lead on board you won't get 250wh/mile
I also think your looking at the 20a rate and unrealisitic prices.
for the 12V 195ah trojan batteries they are 112 lbs and about $500each
50Kwh would be 22 batteries for 2500lbs and $11,000
But that is not real capacity. assuming a 1hr rate of about 1/2 that
(Anyone know what that 1hr rate is?, I use AGMS)
So you are really looking at $22,000 and 5000lbs. Cost is no longer an
issue because space and capability for 5000lbs of lead is impractical.
5000Lbs will effect the on road energy usage, diminishing returns.
By the time I finished writing this someone showed it is even worse than
this!
at $2/ah for 3.3V
2*90ah * 84 cells for 50kwh is 1100lbs and $60,000 !
There is a pseudo pukerts but it has much, much less effect.
So there probably is a sweet spot where it becomes practiacal
But I think the 4 times the cost 1/4 weight rule of thumb is evolving to
3 times the cost 1/3 the weight.
--- End Message ---
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Martin Klingensmith
--- End Message ---
--- Begin Message ---
Hi Marty,
The motor performance curves can be "calculated" or
"tested". You describe pretty well how the tested
curve is generated from test data taken on a
dynamometer. The dyno will have a torque sensor of
some type, so output power is calculated from the
measured torque and RPM.
If your controller limits battery current, then it
will not be a "straight up and down line".
The power out or horsepower shown on the curve is only
for the voltage at which the curve was generated.
When you are in current limit, the controller is
reducing the voltage to the motor, so the horsepower
and speed of the motor are less than shown on the
curve. Once out of current limit and the controller
is applying maximum voltage to the motor, you should
follow the speed and power curve closely. As you
accelerate, the RPM increases and current, torque and
power decrease, as shown on the curve.
Jeff
--- Marty Hewes <[EMAIL PROTECTED]> wrote:
> Hi Guys,
>
> Speaking of these curves, correct me if I'm wrong,
> before I do something
> stupid and expensive.
>
> The way these curves are generated is?
>
> Apply the specified voltage to the motor while
> Applying physical load until a given current is
> reached at the specified
> voltage
> Measure Torque
> Measure RPM
> Calculate HP based on torque and RPM?
> Or measure HP and RPM and calculate torque?
> Calculate efficiency based on watts in and HP out?
>
> This appears to be abstract to use because in
> practice, we tend to limit
> current and let volts rise with RPM until we can't
> achieve the chosen
> current? So we're really operating in a straight up
> and down line at
> constant torque and increasing HP beneath our chosen
> current point until we
> hit the point where we're back EMF limited and the
> current drops with
> further RPM increase? So we will only see the HP
> listed on the graph for a
> moment as we hit pack voltage = motor voltage before
> current drops?
>
> TIA,
> Marty
>
> ----- Original Message -----
> From: "Steve Peterson"
> <[EMAIL PROTECTED]>
> To: <ev@listproc.sjsu.edu>
> Sent: Wednesday, May 09, 2007 11:17 AM
> Subject: Re: Motor equations
>
>
> > Yup, that helps me understand how the concepts
> relate to the curves. Now
> > all I have to do is figure out how to model the
> curves. Many thanks.
> > --Steve
> >
> > On Wed, 2007-05-09 at 08:32 -0700, Jeff Major
> wrote:
> >> Hi Steve,
> >>
> >> Good question.
> >>
> >> The plots you refer to are amps vs torque and RPM
> vs
> >> torque. So this makes it a combination of the
> two
> >> basic equations. Plus the fact that the torque
> in the
> >> equation is the *electromagnetic torque* and not
> the
> >> output torque. The plots use output torque which
> >> accounts for losses (friction, windage and core).
> >> These losses are significant at light loads on
> the
> >> series motor where RPM is high. This tends to
> >> straighten out the amp vs torque curve, but it
> still
> >> bends down somewhat at light loads.
> >>
> >> Also, the Eg in the equation is the generated
> voltage
> >> or back EMF and not the applied voltage. So one
> has
> >> to account for the resistance and brush drop.
> These
> >> are low at light loads so affect the RPM vs
> torque in
> >> the opposite manner.
> >>
> >> Hopes that helps.
> >>
> >> Jeff
> >>
> >>
> >>
> >> --- Steve Peterson <[EMAIL PROTECTED]>
> >> wrote:
> >>
> >> > Thanks, Jeff...
> >> >
> >> > Your explanation makes sense, but leaves me
> with a
> >> > new question:
> >> >
> >> > If Torque is proportional to Flux, and Flux
> varies
> >> > with the current, why
> >> > is the ADC torque vs. amps curve darned near
> linear
> >> > while the rpm vs
> >> > torque curves have a "deep" bend in them?
> >> >
> >> > --Steve
> >> >
> >> > On Wed, 2007-05-09 at 07:15 -0700, Jeff Major
> wrote:
> >> > > Steve,
> >> > >
> >> > > RPM = Ks * Eg / Flux
> >> > >
> >> > > where Ks = machine constant (including units
> >> > > conversion), Eg = generated voltage.
> >> > >
> >> > > Torque = Kt * Ia * Flux
> >> > >
> >> > > where Kt = machine constant (including units
> >> > > conversion), Ia = armature current.
> >> > >
> >> > > Although equations appear linear, the Flux is
> not
> >> > a
> >> > > linear function of current for the series
> motor
> >> > due to
> >> > > saturation, so the Torque vs RPM
> characteristic is
> >> > > curved.
> >> > >
> >> > > Jeff
> >> > >
> >> >
> >> >
> >>
> >>
> >>
> __________________________________________________
> >> Do You Yahoo!?
> >> Tired of spam? Yahoo! Mail has the best spam
> protection around
> >> http://mail.yahoo.com
> >>
> >
> >
>
>
__________________________________________________
Do You Yahoo!?
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--- End Message ---
--- Begin Message ---
[EMAIL PROTECTED] wrote:
Actually, there are electronics that can measure battery impedance real
time from no load to full load. I have only seen these when I worked at
Lockheed Martin about 8 years ago. The instrument applies an AC signal
across the battery and measures the current of the AC signal. Much the
same way as an ohm meter, but, since the signal is AC it is independent
of the DC or load on the battery. It is a great instrument that is used
heavily at that shop. I don't remember who the manufacture was. Never
seen one since then.
You find them in car repair and battery shops occasionally. They are
usually a quick-and-dirty way to get a good/weak/bad indication from a
starting battery.
For a starting battery, amphour capacity is largely irrelevant. All you
need is a "high enough" current for "long enough" to start the engine.
The no-load voltage is a crude indicator of state of charge
(full/half/dead), and the voltage *change* with a known load is a rough
indicator of its internal resistance.
For example, 12.5 volts no-load = 50% state of charge. Voltage sags to
10.5v at 100 amps; R = (12.5v - 10.5v) / 100a = 2v/100a = 0.02 ohms (weak).
This type of tester doesn't work as well for deep cycle batteries, or
batteries that are asked to deliver load current for a significant
length of time. That's because of the large change in internal
resistance over time due to the factors I mentioned. A battery can have
an initially low internal resistance, but that climbs very fast under
load, rendering it fine as a starting battery but useless for extended
EV use.
Ultimately, if your EV discharges the battery over a 1-hour period in
normal use, the only reasonable test is one that discharges it over a
similar period.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Steve,
I think you are putting too much inference on the fan
when in comes to the speed, torque, current
characteristic on the motor. Back in days of old when
I drew motor curves, the title block included the
ventilation method because most curves included the
rating (time-on vs temp). The effect of the fan on
the speed-torque curve was ignored. Those motors were
not running at high speeds and loss due to the fan was
well within the margin of error.
I have looked at the two curves for the FB1-4001 motor
from the link you provided. C-59 and XC-59. There is
a considerable difference between the two on the
torque per amp and 75 volt speed curve. This is more
than just a fan. I would bet the fan did not enter
into it at all. The C-59 curve title block indicates
"CCw Rotation". It has higher speed and amps than
XC-59. So maybe the difference is due to a brush
shift. Just a guess. But maybe the guy at ADC who
drew the curves was a bit off that day.
Jeff
--- Steve Peterson <[EMAIL PROTECTED]>
wrote:
> On Wed, 2007-05-09 at 10:27 -0700, Roger Stockton
> wrote:
>
> > That's odd; do you mean an FB4001 that has had the
> internal fan removed,
> > or a stock 9" with the original internal fan?
>
> Roger,
>
> Here's the path I've taken:
>
> I got the curves from the EVParts site:
>
>
http://www.evparts.com/shopping/product_details.php?id=536&product_id=1128
>
> All I know is one graph says "Ventilated - Not Fan
> Cooled"
> and the other says "Fan Cooled". The EVParts site
> doesn't say which
> version they sell, so as a newbie, I was at a loss
> to really be sure
> which version Uwe's calculator referred to.
>
> But it gets better: I was alerted to this whole
> issue because I noticed
> a couple of local EVers had directed the output of
> some small external
> fans into their ADC motors--so I figured they were
> creating the "fan
> cooled" version. I didn't think to ask the owners
> about it at the time,
> however.
>
> Having noticed that the curves were much better for
> the fan-cooled
> version (as you'd expect), I figured I'd sim it and
> see what it would do
> for me....that's when I took a hard look at Uwe's
> numbers.
>
>
> >
> > The first entry on Uve's motor page is for the
> standard FB4001 (with
> > internal fan):
> >
> >
>
<http://www.geocities.com/CapeCanaveral/Lab/8679/motor.html>
>
> That may be, but if you use Uwe's (n,k) values
> (1.55, .0085) for the
> FB4001 and calc the points for the torque vs. amps
> line, you'll find
> they match (within 6-7% worst case) the ADC chart
> for "Ventilated--not
> fan cooled" and fit less well the chart for "Fan
> Cooled". That (plus the
> EVers with their fans) lead me to believe the
> calculator was really
> modelling the "not fan cooled" motor.
>
> >
> > At the top of this page are the equations that his
> calculator uses to
> > model the motor behaviour. The problem I have
> with them is that they
> > are not based on the actual physics of a series
> motor but rather are an
> > approximate fit to the motor curve over some
> range. The problem here is
> > that since they are not based on the underlying
> physics they generally
> > don't model the motor very well as the calculator
> extrapolates beyond
> > the range over which the parameters were
> calculated to result in a
> > decent fit to the actual motor behaviour.
>
> I agree. I did a bunch of calcs, noticed the same
> thing, and was
> bothered for the same reason--the formula didn't
> represent any physics
> that I could find a description for. That's when I
> decided to yell for
> help :-)
>
> >
> > Jeff Major has stepped up and offered the
> theoretical equations for a
> > series motor, and has noted that these strictly
> model the electrical
> > behaviour of the motor, they do not account for
> such practicalities as
> > the losses associated with the internal fan (a
> function of the second or
> > third power of the RPM), or bearing and brush
> friction, nor brush
> > losses, or armature reaction, or field saturation,
> etc. For instance,
> > notice that theory predicts that torque will vary
> with the square of the
> > current, yet the actual motor curves tend to show
> that it actually
> > varies by the current raised to about 1.2 or so.
> >
> > If you are looking to model a stock FB4001, you
> can probably use Uve's
> > calculator and its model provided you don't trust
> any predictions it
> > makes for high RPM/low torque or low RPM/high
> torque extremes.
>
> I'd do that, but the whole reason I started looking
> into this is that I
> *do* need some confidence in the numbers at the low
> RPM/high torque
> extreme because I actually need more RPM at the
> higher torque levels if
> I'm going to climb some 8% grades at 50 mph or so.
> The curves for the
> "Fan cooled" version appear to help a bit in that
> regard.
>
> >
> > If you wanted to, you could plug Uve's model
> equations and parameters
> > into a spreadsheet and plot the resulting curves
> against the factory
> > curves for the motor and see where the error is,
> and if it is small
> > enough to ignore.
>
> I've done spot-checks and the discrepancies bothered
> me enough to make
> me wonder if I was doing something wrong or the
> parameters weren't right
> or the equation was just faulty. Knowing which chart
> (fan vs. no fan) to
> compare to would help, too.
>
> >
> > If you have removed the internal fan, then you
> can't rely on the factory
> > curves anymore if you want good accuracy. The
> internal fan represents a
> > loss that increases (rapidly!) with RPM, so if you
> did use the stock
> > motor data you should be confident that your real
> life results should be
> > a bit better than the predictions.
>
> Haven't touched the motor. Don't even have one to
> touch :-(
>
> >
> > If you want to take up the challenge of modelling
> the FB4001 accurately,
> > I would start by plugging the manufacturer's data
> into a spreadsheet,
> > then plug in the theoretical equations for a
> series motor, and then add
> > to them equations to model the losses (drag)
> associated with the
> > internal fan/windage and bearings. Play with the
> parameters until the
> > curves are a resonably good match to the
> manufacturer's data. Now you
> > have a model that predicts the motor behaviour and
> isolates the
> > contribution of the internal fan so that you can
> remove the portion of
> > the equation associated with the internal fan
> losses and have a
> > resonable confidence that the predictions will
> yield a fair prediction
> > of the FB4001 behaviour with the internal fan
> removed.
> >
> > This is the sort of thing I generally enjoy
> fooling around with, but I
> > just haven't got the spare time right now to do
> it...
>
> Understand. Hopefully, once we get the fan vs. no
> fan thing sorted out
> things will be a bit clearer.
>
> >
> > Hope this helps,
>
> Tremendously. Very much appreciated.
>
> --Steve
>
>
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--- Begin Message ---
Folks, thanks, but it's not really necessary (or desirable) to post items like
this.
I'm taking care of the situation off-list. Every day I send private email to
those
whose email systems need to be reconfigured for the EVDL.
We're seeing more html email because we have lots of new members. That's a
good thing, no?
Even if I never left the house, I could tell when gasoline prices were up by
the
number of new EVDL subscribers. ;-)
--- End Message ---
--- Begin Message ---
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* ---REMAINDER OF MESSAGE TRUNCATED--- *
* This post contains a forbidden message format *
* (such as an attached file, a v-card, HTML formatting) *
* Lists at sjsu.edu only accept PLAIN TEXT *
* If your postings display this message your mail program *
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--- Begin Message ---
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, May 10, 2007 9:28 AM
Subject: Re: AGNS bike garners 120volt record
> Hey! Congratulations on your new record(s). So how many times did you
> break the record this week?!
> Anyway, my condolences to AGNS's motors.
> Great stuff!!
> Heidi and I are going to the Power of DC this year!!! Yea!
> See you there...
>
> Ken
> Hi Ken an' Heidi an' EVerybody else;
Power of DC? Show of hands! Anybody ELSE going? Time is ticking down
towards THE day.I know alota guyz will be going. Just curious.
Seeya There?
Bob
>
>
> -----Original Message-----
> From: [EMAIL PROTECTED]
> To: ev@listproc.sjsu.edu
> Sent: Thu, 10 May 2007 7:08 AM
> Subject: AGNS bike garners 120volt record
>
> Springtime fianllay came to Thompson Raceway on Wednesday night with
> temps in the mid 70's and light wind.
> The Lawless crew and AGNS were there for grudge night with hopes of a
> 120 volt record run and 100 mph. Having let work get in the way of our
> racing we didn't get to the track until after 6 pm. We had just enough
> time for 2 runs during T-N-T. First run 13.85 @ 92.47. A quick recharge
> later and a 13. 78 @ 94.723. They are within 1% so the second time
> should stick as the new 120 volt record.
> We were headed in the right direction but since we were the last TNT
> run we didn't have time to recharge before eliminations began a few
> minutes later. I talked to the starter and he agreed to allow us a
> timed run whenever we were ready. What cool folks! Well you know what
> happens when you have too much time to think. Should we make another
> 120volt run? Experience with this bike tells me that it probably would
> have been a 13.6? at 95-96 mph. Not bad considering we were running a
> single starnd of 10 Hawkers and 60% less battery than we had at 96
> volts. Should we bump up to 144 volts or go all the way and see what
> 192 volts will do? We stuffed 6 more Hawkers in there and were floating
> around 215 volts by the time we were in staging. We positioned
> ourselves at the 600 ft mark and waited. Denis came down the track like
> he was sent from a silent cannon but he must have wanted to show off
> because when he got right in front of us at 600 ft. the motors put on a
> nice light show. Safe to say I now know how high I can't set the motor
> voltage. All kinds of nasty noises accompanied the sparks and AGNS
> snapped, crackled, and popped down the rest of the track all the way to
> a 13.39 @ 93.83. We headed down track to a find pair of smoldering Perm
> motors, a heartbroken Denis that he had done this to his AGNS and an
> otherwise ready to run bike. We'll open up the motors today. Should
> find all kinds of parts to hang on the wall. What a week of racing! 3
> new NEDRA recors, One flame job, and one group of addicted EV racers.
> When will AGNS get 100 mph? Next week at 144 volts I hope.
>
> Shawn Lawless
> ________________________________________________________________________
>
> AOL now offers free email to everyone. Find out more about what's free
> from AOL at AOL.com.
>
> ________________________________________________________________________
> AOL now offers free email to everyone. Find out more about what's free
> from AOL at AOL.com.
>
--- End Message ---
--- Begin Message ---
I'd love to be there. But being 3,500 miles away I'll just have to be
content with the T shirt excellently designed by Crip from last year!
Who's running this year? Any new vehicles? Take a video camera or two
and put it up on YouTube when you're back!
Good luck to all the competitors from the two girls in Bristol, UK!
We'll be doing the Tour De Prestigne Electric bike race on Sat/Sun in
Wales and have a stand there with our UK EV group, BVS.
Nikki.
_______________________________
Old car? New tricks?
Visit aminorjourney.com to see the transformation from Hebe to EV.
E-minor isn't just a key any more...
_______________________________
On May 10, 2007, at 4:22 PM, Bob Rice wrote:
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, May 10, 2007 9:28 AM
Subject: Re: AGNS bike garners 120volt record
Hey! Congratulations on your new record(s). So how many times did you
break the record this week?!
Anyway, my condolences to AGNS's motors.
Great stuff!!
Heidi and I are going to the Power of DC this year!!! Yea!
See you there...
Ken
Hi Ken an' Heidi an' EVerybody else;
Power of DC? Show of hands! Anybody ELSE going? Time is ticking
down
towards THE day.I know alota guyz will be going. Just curious.
Seeya There?
Bob
-----Original Message-----
From: [EMAIL PROTECTED]
To: ev@listproc.sjsu.edu
Sent: Thu, 10 May 2007 7:08 AM
Subject: AGNS bike garners 120volt record
Springtime fianllay came to Thompson Raceway on Wednesday night with
temps in the mid 70's and light wind.
The Lawless crew and AGNS were there for grudge night with hopes of a
120 volt record run and 100 mph. Having let work get in the way of
our
racing we didn't get to the track until after 6 pm. We had just
enough
time for 2 runs during T-N-T. First run 13.85 @ 92.47. A quick
recharge
later and a 13. 78 @ 94.723. They are within 1% so the second time
should stick as the new 120 volt record.
We were headed in the right direction but since we were the last TNT
run we didn't have time to recharge before eliminations began a few
minutes later. I talked to the starter and he agreed to allow us a
timed run whenever we were ready. What cool folks! Well you know what
happens when you have too much time to think. Should we make another
120volt run? Experience with this bike tells me that it probably
would
have been a 13.6? at 95-96 mph. Not bad considering we were running a
single starnd of 10 Hawkers and 60% less battery than we had at 96
volts. Should we bump up to 144 volts or go all the way and see what
192 volts will do? We stuffed 6 more Hawkers in there and were
floating
around 215 volts by the time we were in staging. We positioned
ourselves at the 600 ft mark and waited. Denis came down the track
like
he was sent from a silent cannon but he must have wanted to show off
because when he got right in front of us at 600 ft. the motors put
on a
nice light show. Safe to say I now know how high I can't set the
motor
voltage. All kinds of nasty noises accompanied the sparks and AGNS
snapped, crackled, and popped down the rest of the track all the
way to
a 13.39 @ 93.83. We headed down track to a find pair of smoldering
Perm
motors, a heartbroken Denis that he had done this to his AGNS and an
otherwise ready to run bike. We'll open up the motors today. Should
find all kinds of parts to hang on the wall. What a week of racing! 3
new NEDRA recors, One flame job, and one group of addicted EV racers.
When will AGNS get 100 mph? Next week at 144 volts I hope.
Shawn Lawless
_____________________________________________________________________
___
AOL now offers free email to everyone. Find out more about what's
free
from AOL at AOL.com.
_____________________________________________________________________
___
AOL now offers free email to everyone. Find out more about what's
free
from AOL at AOL.com.
--- End Message ---
--- Begin Message ---
I just got done with this conversation with a co-worker....
It's funny the way we work things out.
I have done (really rough) estimated total ownership costs.
It's true, 6v GC batts are the cheapest.
But then "we" decide we don't want to deal with the hassle of maintenance
required by flooded lead and we "KNOW" that lithium or nickel is more expensive
than lead so we load our cars up with "maintenance free" Optima's or the like.
Guess what!
Optimas are the MOST EXPENSIVE solution. Almost thrice the total cost of
lithium; and that's if you do the 5 lifetime replacements yourself and put zero
value on your time to do it.
Out to 150,000 miles or more "my" estimated cost goes; from least to most....
(fixed width font)
Battery $ per mile
GC's .08
Lithium .09
NiMH .10
Orbital .11
NiCad .21
Optima .27
What "we" really need is what Victor said years ago.... A paradigm shift,
prepaying for energy. Accept the fact that your batteries are a very large
portion of your energy cost, and not just a storage device. A large upfront
cost will pay off in the long run. Much like solar, wind etc.
--
Stay Charged!
Hump
I-5, Blossvale NY
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> Behalf Of Jeff Shanab
> Sent: Thursday, May 10, 2007 9:43 AM
> To: Electric Vehicle Discussion List
> Subject: Re: Doin' the math
>
> huh? You made me check and I can't even get close to your differences
> But I think your choice of 50Kwh is amplifing the cost difference ,
> ignoring or not taking advantage of the weight difference.
>
> First it is a lofty goal, 50kwh/250wh/mile is 200 miles range. but with
> over 5000lbs of lead on board you won't get 250wh/mile
>
> I also think your looking at the 20a rate and unrealisitic prices.
>
> for the 12V 195ah trojan batteries they are 112 lbs and about $500each
> 50Kwh would be 22 batteries for 2500lbs and $11,000
> But that is not real capacity. assuming a 1hr rate of about 1/2 that
> (Anyone know what that 1hr rate is?, I use AGMS)
> So you are really looking at $22,000 and 5000lbs. Cost is no longer an
> issue because space and capability for 5000lbs of lead is impractical.
> 5000Lbs will effect the on road energy usage, diminishing returns.
>
> By the time I finished writing this someone showed it is even worse than
> this!
>
>
> at $2/ah for 3.3V
> 2*90ah * 84 cells for 50kwh is 1100lbs and $60,000 !
> There is a pseudo pukerts but it has much, much less effect.
>
> So there probably is a sweet spot where it becomes practiacal
>
> But I think the 4 times the cost 1/4 weight rule of thumb is evolving to
> 3 times the cost 1/3 the weight.
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, May 10, 2007 11:18 AM
Subject: Re: PLEASE FIX YOUR EMAIL CLIENTS!
> Folks, thanks, but it's not really necessary (or desirable) to post items
like this.
> I'm taking care of the situation off-list. Every day I send private email
to those
> whose email systems need to be reconfigured for the EVDL.
>
> We're seeing more html email because we have lots of new members. That's
a
> good thing, no?
>
> Even if I never left the house, I could tell when gasoline prices were up
by the
> number of new EVDL subscribers. ;-)
> That and who's scene" Who Killed the Electric Car" movie! Throw in
"Inconvenient Truth," Iraq for Sale" and others of that genre.
David? can ya make it down to Power of DC?
Seeya?
Bob
--- End Message ---
--- Begin Message ---
So when you pull away from a stop at your chosen current limit, your torque
is more or less constant, until you reach the voltage and RPM on the curve,
but what accelerates you is HP (watts)?, which is relative to that torque
and whatever RPM your drivetrain allows, right? So the only point you would
actually get the HP on the curve is at the point the controller hits the
voltage specified in the graph (where you reach the RPM on the graph)?
I'm confused. I'm starting with the assumption that the more watts you can
get to the wheels, the more acceleration you will experience. Seems
logical, but the math fails me. I'm struggling with the idea that HP is
directly related to watts (implied by the formula 1KW = Horsepower x 0.746),
and HP is a product of torque and RPM (Torque x Engine speed) / 5,252 =
Horsepower). It kinda sounds like at zero RPM, you'd have no HP, draw no
watts (thus no current), produce no torque, and go nowhere. But we know
that's not true. Do electric motors use a different formula where they can
produce HP, and therefore apply wattage to the rear wheels at zero RPM?
Someone please show me where I'm going off track, this is driving me nuts.
TIA,
Marty
----- Original Message -----
From: "Jeff Major" <[EMAIL PROTECTED]>
Hi Marty,
The motor performance curves can be "calculated" or
"tested". You describe pretty well how the tested
curve is generated from test data taken on a
dynamometer. The dyno will have a torque sensor of
some type, so output power is calculated from the
measured torque and RPM.
If your controller limits battery current, then it
will not be a "straight up and down line".
The power out or horsepower shown on the curve is only
for the voltage at which the curve was generated.
When you are in current limit, the controller is
reducing the voltage to the motor, so the horsepower
and speed of the motor are less than shown on the
curve. Once out of current limit and the controller
is applying maximum voltage to the motor, you should
follow the speed and power curve closely. As you
accelerate, the RPM increases and current, torque and
power decrease, as shown on the curve.
Jeff
--- Marty Hewes <[EMAIL PROTECTED]> wrote:
Hi Guys,
Speaking of these curves, correct me if I'm wrong,
before I do something
stupid and expensive.
The way these curves are generated is?
Apply the specified voltage to the motor while
Applying physical load until a given current is
reached at the specified
voltage
Measure Torque
Measure RPM
Calculate HP based on torque and RPM?
Or measure HP and RPM and calculate torque?
Calculate efficiency based on watts in and HP out?
This appears to be abstract to use because in
practice, we tend to limit
current and let volts rise with RPM until we can't
achieve the chosen
current? So we're really operating in a straight up
and down line at
constant torque and increasing HP beneath our chosen
current point until we
hit the point where we're back EMF limited and the
current drops with
further RPM increase? So we will only see the HP
listed on the graph for a
moment as we hit pack voltage = motor voltage before
current drops?
TIA,
Marty
----- Original Message -----
From: "Steve Peterson"
<[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Wednesday, May 09, 2007 11:17 AM
Subject: Re: Motor equations
> Yup, that helps me understand how the concepts
relate to the curves. Now
> all I have to do is figure out how to model the
curves. Many thanks.
> --Steve
>
> On Wed, 2007-05-09 at 08:32 -0700, Jeff Major
wrote:
>> Hi Steve,
>>
>> Good question.
>>
>> The plots you refer to are amps vs torque and RPM
vs
>> torque. So this makes it a combination of the
two
>> basic equations. Plus the fact that the torque
in the
>> equation is the *electromagnetic torque* and not
the
>> output torque. The plots use output torque which
>> accounts for losses (friction, windage and core).
>> These losses are significant at light loads on
the
>> series motor where RPM is high. This tends to
>> straighten out the amp vs torque curve, but it
still
>> bends down somewhat at light loads.
>>
>> Also, the Eg in the equation is the generated
voltage
>> or back EMF and not the applied voltage. So one
has
>> to account for the resistance and brush drop.
These
>> are low at light loads so affect the RPM vs
torque in
>> the opposite manner.
>>
>> Hopes that helps.
>>
>> Jeff
>>
>>
>>
>> --- Steve Peterson <[EMAIL PROTECTED]>
>> wrote:
>>
>> > Thanks, Jeff...
>> >
>> > Your explanation makes sense, but leaves me
with a
>> > new question:
>> >
>> > If Torque is proportional to Flux, and Flux
varies
>> > with the current, why
>> > is the ADC torque vs. amps curve darned near
linear
>> > while the rpm vs
>> > torque curves have a "deep" bend in them?
>> >
>> > --Steve
>> >
>> > On Wed, 2007-05-09 at 07:15 -0700, Jeff Major
wrote:
>> > > Steve,
>> > >
>> > > RPM = Ks * Eg / Flux
>> > >
>> > > where Ks = machine constant (including units
>> > > conversion), Eg = generated voltage.
>> > >
>> > > Torque = Kt * Ia * Flux
>> > >
>> > > where Kt = machine constant (including units
>> > > conversion), Ia = armature current.
>> > >
>> > > Although equations appear linear, the Flux is
not
>> > a
>> > > linear function of current for the series
motor
>> > due to
>> > > saturation, so the Torque vs RPM
characteristic is
>> > > curved.
>> > >
>> > > Jeff
>> > >
>> >
>> >
>>
>>
>>
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>
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