EV Digest 6959
Topics covered in this issue include:
1) Re: Manly EV's, RE: EV are for girls blog
by "Phil Marino" <[EMAIL PROTECTED]>
2) v
by Ricky Suiter <[EMAIL PROTECTED]>
3) OT Re: Make it
by Lock Hughes <[EMAIL PROTECTED]>
4) Re: EV air conditioning, how to connect motor?
by "Shaun Williams" <[EMAIL PROTECTED]>
5) RE: Cheap
by "Roger Stockton" <[EMAIL PROTECTED]>
6) Re: AGM vs Gel
by "Tehben Dean" <[EMAIL PROTECTED]>
7) Re: Potential BMS solution for lithium-ion packs.
by "Shaun Williams" <[EMAIL PROTECTED]>
8) Re: ???kWh EV battery pack
by "Tehben Dean" <[EMAIL PROTECTED]>
9) Re: EV air conditioning, how to connect motor?
by Christopher Robison <[EMAIL PROTECTED]>
10) Re: EV air conditioning, how to connect motor?
by Christopher Robison <[EMAIL PROTECTED]>
11) Re: Electrical/Mechanical Engineering
by [EMAIL PROTECTED] (Dana Havranek)
12) RE: EV air conditioning, how to connect motor?
by Christopher Robison <[EMAIL PROTECTED]>
13) To Gear or Not to Gear a Motorcycle (was Manly EV's, etc.)
by "Loni" <[EMAIL PROTECTED]>
14) Re: ???kWh EV battery pack
by "Peter VanDerWal" <[EMAIL PROTECTED]>
15) Re: Home built hybrid-electrics
by "Peter VanDerWal" <[EMAIL PROTECTED]>
16) Re: Cheap "balancer" for A123 pack
by Bill Dube <[EMAIL PROTECTED]>
17) Re: To Gear or Not to Gear a Motorcycle (was Manly EV's, etc.)
by "Peter VanDerWal" <[EMAIL PROTECTED]>
18) RE: EV air conditioning, how to connect motor?
by "Jim, Saturn Guy" <[EMAIL PROTECTED]>
19) Re: To Gear or Not to Gear a Motorcycle (was Manly EV's, etc.)
by "Mark Eidson" <[EMAIL PROTECTED]>
20) Re: S10 transmission
by "Jim, Saturn Guy" <[EMAIL PROTECTED]>
21) Re: Controler Oil
by "Phelps" <[EMAIL PROTECTED]>
22) Brush timing advance, nothing new :-)
by Bill Dube <[EMAIL PROTECTED]>
23) I have an IDEA!
by "Joseph T. " <[EMAIL PROTECTED]>
24) Re: Brush timing advance, nothing new :-)
by "Joseph T. " <[EMAIL PROTECTED]>
--- Begin Message ---
From: "Ian Jordan" <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
Subject: Re: Manly EV's, RE: EV are for girls blog
Date: Wed, 27 Jun 2007 12:03:40 -0700
Work is work. If you put a gearbox in in order to convert torque to
RPM, this is identical to upping the voltage and reducing the current
via a battery pack.
The gearbox will just require more amps from the battery, so this is
the same as "dumping in more current".
There's no way to continue to accelerate without generating at least X
watts. Those watts either come from volts or amps. Choose one.
Ian - you may understand this, but in case others don't:
You need BOTH voltage and current to produce power. One is not enough.
The product of the two (at least for DC) is power in units of watts.
Phil Marino
On 6/26/07, Loni <[EMAIL PROTECTED]> wrote:
Of course I'd love to just dump in more voltage or current, but
design constraints won't allow it. Will changing gears allow me to stay in
the fat part of the motor's torque curve while continuing to accelerate to
max speed, or should I just wring the motor out and accept whatever output
it's capable of as current demand outstrips pack capacity?
_________________________________________________________________
Get a preview of Live Earth, the hottest event this summer - only on MSN
http://liveearth.msn.com?source=msntaglineliveearthhm
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--- Begin Message ---
GEM's and Ford Th!nk neighbor's both use the Deka 8G31
as their stock gel battery (although both re-label
them and charge a premium of course). They both use a
350 amp GE controller and both seem to get good
battery life with them.
I know this doesn't sound too impressive, but for a
NEV it is. A person recently posted to the Yahoo NEV's
group saying he was finally replacing his 2 year old
Deka's after about 9,000 miles of use. He drove it
about 20 miles a day on average (one cycle) so they
were getting good discharges regularly. He did
specifically order a car that the dealer did not have
on their lot so he would get a brand new one with a
brand new fresh pack.
I'm just now getting some time on them in the field (I
fix NEV's on the side) but thus far they seem to be
staying very balanced, and granted we're only talking
6 batteries in series, but they seem to be staying
more balanced voltage-wise than their flooded option
of Trojan 30XHS's.
Later,
Rick
92 Saturn SC conversion
AZ Alt Fuel plates "ZEROGAS"
Glendale, AZ
> >
> > Date: Wed, 27 Jun 2007 00:44:13 -0800
> From: Mike Willmon <[EMAIL PROTECTED]>
> Subject: RE: AGM vs Gel
> To: ev@listproc.sjsu.edu
>
> David, how about the 8G31's? Would that be a big
> enough battery so as to handle the 300 Amps Tehben
> is looking at?
>
> Mike,
> Anchorage, Ak.
>
____________________________________________________________________________________
Food fight? Enjoy some healthy debate
in the Yahoo! Answers Food & Drink Q&A.
http://answers.yahoo.com/dir/?link=list&sid=396545367
--- End Message ---
--- Begin Message ---
--- Peter Gabrielsson <[EMAIL PROTECTED]> wrote:
> > There was an interesting study some years ago (hmm, I need to find
> my
> > copy). The jist of it is that Incompetent people not only don't
> > realize they are incompetent, but they are completely unable to
> > recognize competency in others. So they always "know" they are
> > right, and anyone that disagrees with them is obviously stupid.
> >
> > Sound familiar?
> >
>
> Yes, I used to work for that guy!
Link to January, 2000 NY Times report on that study:
http://tinyurl.com/yo3vsb
Lock
Toronto
Ask a question on any topic and get answers from real people. Go to
Yahoo! Answers and share what you know at http://ca.answers.yahoo.com
--- End Message ---
--- Begin Message ---
On 6/28/07, Christopher Robison <[EMAIL PROTECTED]> wrote:
Has anyone connected a relatively modern car A/C compressor to a motor,
inline? The discussion about belts and chains is reminding me that I
need to figure this out, and I'd like to avoid a belt if I can --
amongst other reasons, I've still not found a good source for small
lightweight K-section ribbed pulleys to fit on a standard keyed shaft or
bushing. So, I'd like to have the motor somehow directly coupled to the
compressor.
Hi Christopher,
I used the original ICE pulley to drive the original A/C compressor
and alternator. All that was needed was a bit of machining to bore it
out and make up a bush insert the right dimension for the motor shaft.
Most engineering shops wouldn't charge too much for this sort of job.
Here's a rough drawing I used as a guide for the machinist;
http://www.electric-echo.com/PulleyDrawing.htm
and lots of pic's;
http://www.electric-echo.com/journal3.htm
Then I just bought a smaller K-section belt to fit.
Shaun
www.electric-echo.com
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Shaun Williams wrote:
> Thanks Roger, can you suggest an off-the-shelf product that could be
> used for this? That is, a fusible material that could be spot welded
> to either the cell-end or existing cell-tab, or is it simply a case of
> make it thin enough and it will give?
I believe that is it. I think more detailed mention of it was made by
Bill Dube and/or Rich Rudman back during discussions of the cells in the
V28 packs or the A123 cells (don't recall which). The basic idea is
that you need to weld one or more tabs to each end of the cell to
connect it to the main bars/plates anyway, so simply size the tab to
easily carry the expected current but to blow open if this limit is
grossly exceeded. My fuzzy memory is that there was mention of the
cells being used/available with either 1 or two tabs on each end, and
that each tab was either good for 75A or made a fairly nice 75A fuse.
> I'm thinking that should a module's capacity become severely depleted
> due to multiple blown cells it could be detected under load with a
> voltage comparison to other modules.
Yes, I think this is possibly the only economic/practical means of
sensing such a condition. Essentially, there must be an over/under
voltge monitor/BMS on each module anyway, so give it the smarts to
estimate the module's impedance based on voltage variation with varying
load. It would only work if the cell impedance was relatively well
controlled vs SOC and SOH (state of health)/life so that the increase
due to the loss of 10-20% of the paralleled cells is readily
distinguishable from the normal variations.
I am still of the opinion that it would not be economic to replace
failed cells in a module vs repalcing the module itself, but at least
this approach has the potential of lighting an idiot light, etc. to
alert the user to the need for battery service before a module fails
entirely and leaves them stranded.
Cheers,
Roger.
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--- Begin Message ---
Well maybe I will go with Gel and do something for heating.
I am getting a NLG513-SA BRUSA battery charger so I should be able to
program it to do whatever charging scheme WE ;) come up with.
One thing I am wondering (Victor) with the Regen is that limited so it
won't overcharge the pack?
On 6/27/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
I have owned several EVs powered by AGM and one with Deka Gel. In the winter
I found AGM and Gel both lost a lot of range when cold. I think all lead
acid batteries need to be heated in cold weather for best results. I would also
guess for long life heat should be done as it puts less demand on the
batteries.
One point I cannot stress enough is AGM batteries are hard to keep in
balance. The gel batteries are outstanding in staying in balance. This is a
major
difference and is the reason Solectria made hundreds of EVs with them. It was
not a decision based on cost savings. Solectria found the Gel battery to be
superior battery in long life and staying balanced when in series. Gels do
hold a charge very well. I have a used ones that were removed from an EV with
over 18 thousand miles and they still hold 13.1 volts after a year. It is
amazing how long they will hold a charge. AGMs hold a charge well also but not
as
long as a gel.
If your charging algorithm is set up correct for Gel you will get way longer
life than with AGM batteries. If you do not need the high amperage rate an
AGM delivers then the Gel from my experience would be your best option. I
never notice enough difference in cold weather performance to say AGM or Gel
was
better than another. I never did any type of testing that so this is just an
opinion.
As far as the cold performance when it gets under 50 degrees all lead
batteries start dropping off. Many here on the list have shared great ideas and
ways on keeping a pack warm. I would rather come up with a way to keep the
pack
above 50 degrees then keeping a pack of AGM in series in balance. Lee's
battery balancer putting a charge to each battery for balance is the best way. A
charger for each battery not high tech but it does what is needed. I just
don't feel over charging some batteries to bring up others is the best answer.
It
is a compromise for not being able to put a direct charge to the low
batteries.
I am no battery expert but I have been impressed by the Deka gel batteries.
I cannot say about the other brands of Gel batteries but the Deka I would
recommend.
Don Blazer
--
TEhben
'hElix EV'
evalbum: http://www.austinev.org/evalbum/1225
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--- Begin Message ---
Hi Tom,
That's quite a find. At my level of electronic proficiency it'd take
me weeks to pore through that pdf! Hopefully the engineer types here
will give it a nanosecond once-over.
The way things are looking at the moment, for me personally, this
might be too complex and yet not have the flexibility I'm looking for.
Thanks,
Shaun.
www.electric-echo.com
--- End Message ---
--- Begin Message ---
So do people usually go to only 50%DOD or all the way to 80%DOD?
If I spec a battery at 100Ah 20hr rate (could someone explain the C's
discharge measurement?) I need to subtract 40% to approximate the
1hr/1C
Roughly speeking you will need 40% more capacity at the 20hr rate to equal
the 1hr rate.
so that leaves 60Ah and if I only drain it to 80% that leaves 48Ah of
usable capacity.... correct?
And 48ah x 312v = 14976w ~ 15kwh
Count for 4-5 miles range per each 1 kWh on board of good tuned EV.
15kwh x 4 = 60. So with 26 100ah batteries at 80%DOD we get an
approximate 60mile range.
Comments....?
--
TEhben
'hElix EV'
evalbum: http://www.austinev.org/evalbum/1225
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--- Begin Message ---
On Thu, 2007-06-28 at 07:54 +1000, Shaun Williams wrote:
> Hi Christopher,
>
> I used the original ICE pulley to drive the original A/C compressor
> and alternator. All that was needed was a bit of machining to bore it
> out and make up a bush insert the right dimension for the motor shaft.
> Most engineering shops wouldn't charge too much for this sort of job.
>
> Here's a rough drawing I used as a guide for the machinist;
>
> http://www.electric-echo.com/PulleyDrawing.htm
>
> and lots of pic's;
>
> http://www.electric-echo.com/journal3.htm
>
Very interesting -- this looks like a terrific job! One question
though ... do you have a motor that's wired for high torque at low RPM?
I would think it would be better to have a smaller drive pulley compared
to the compressor pulley; yours is larger. What are the specs on your
motor, and with what voltage are you driving it?
--
Christopher Robison
[EMAIL PROTECTED]
http://ohmbre.org <-- 1999 Isuzu Hombre + Z2K + Warp13!
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--- Begin Message ---
On Wed, 2007-06-27 at 17:58 -0500, Christopher Robison wrote:
> On Thu, 2007-06-28 at 07:54 +1000, Shaun Williams wrote:
> > Hi Christopher,
> >
> > I used the original ICE pulley to drive the original A/C compressor
> > and alternator. All that was needed was a bit of machining to bore it
> > out and make up a bush insert the right dimension for the motor shaft.
> > Most engineering shops wouldn't charge too much for this sort of job.
> >
> > Here's a rough drawing I used as a guide for the machinist;
> >
> > http://www.electric-echo.com/PulleyDrawing.htm
> >
> > and lots of pic's;
> >
> > http://www.electric-echo.com/journal3.htm
> >
>
> Very interesting -- this looks like a terrific job! One question
> though ... do you have a motor that's wired for high torque at low RPM?
> I would think it would be better to have a smaller drive pulley compared
> to the compressor pulley; yours is larger. What are the specs on your
> motor, and with what voltage are you driving it?
>
<sigh>
Scratch that -- sent it out too fast ... Didn't notice the A/C
compressor was being driven off the traction motor, along with the
alternator. For some reason in my head I was thinking there was another
motor involved for A/C :-)
--
Christopher Robison
[EMAIL PROTECTED]
http://ohmbre.org <-- 1999 Isuzu Hombre + Z2K + Warp13!
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--- Begin Message ---
Pretty much through DiffyQue.
There doesn't seem to be a lot of discussion about engineers and EV's on the
list, though.
>From the posts I see, I'm sure there are plenty out there, but they don't seem
>to chime in as such.
I guess just a little curious what prompted the question.
Maybe engineers might be a little predisposed to get involved with EV's, but
maybe not.
No doubt you don't have to be an engineer to build and operate an EV.
Just need a little mechanic in your bones and some tools.
Dana
-------------- Original message ----------------------
From: "Joseph T. " <[EMAIL PROTECTED]>
> What kind of math is required and, or recommended to become an
> electrical or mechanical engineer?
>
> I hear alot people saying that they're engineers here, so this will
> determine if it's a bluffing!
>
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--- Begin Message ---
On Wed, 2007-06-27 at 13:04 -0700, Alan Brinkman wrote:
> Christopher,
>
> I wrote this huge reply to your message and deleted it and here are the
> key points I can add. I have trouble creating short messages.
>
Thanks for the effort Alan, I really appreciate it. I'm going to fiddle
around with the compressor and see what I can do with it, and I'll refer
back to your email and Roland's and see if I understand more once I have
the parts in front of me. I'm hoping to do something like what you're
talking about, attaching to the front face of the clutch/pulley
assembly, and using the bolt into the shaft end to center everything.
Balancing might be an issue especially if I weld, but we'll see how it
goes...
--
Christopher Robison
[EMAIL PROTECTED]
http://ohmbre.org <-- 1999 Isuzu Hombre + Z2K + Warp13!
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--- Begin Message ---
Work is work. If you put a gearbox in in order to convert torque to
RPM, this is identical to upping the voltage and reducing the current
via a battery pack.
The gearbox will just require more amps from the battery, so this is
the same as "dumping in more current".
There's no way to continue to accelerate without generating at least X
watts. Those watts either come from volts or amps. Choose one.
I think I understand now. Regardless of pack voltage and gearing, when I
demand acceleration the system has to generate X watts. Once the limits of
pack voltage are reached, X watts are achieved by increasing amperage.
Right?
When I look around, though, there doesn't seem to be a one-size-fits-all
solution for every application. There are certainly gray areas with regard
to motor size and output, intended vehicle usage, battery and controller
packaging limitations (particularly with a motorcycle), component weight
(especially as it relates to mass centralization0, and component life
expectancy. As you say, "choose one".
Most of the respondents here have suggested that direct drive is the way to
go. That may be true, but I'm curious whether that's the general consensus
when pack voltage is limited to, say, 120 V due to packaging/range
constraints. If, for example, I hold the motor at 9000 rpm to maintain top
speed, it seems that I would be drawing big amps while unnecessarily
decreasing motor life-expectancy due to centrifugal force (with most
motors). Or I could change gear ratios and still demand the same wattage,
but at a lower motor rpm. True?
I know it seems unrealistic to think that an operator might hold rpms at
9000 for any length of time, but if I'm going to start manufacturing
motorcycles in any volume, I have to condsider every possibility.
Lon Hull,
Portland, OR
On 6/26/07, Loni <[EMAIL PROTECTED]> wrote:
Of course I'd love to just dump in more voltage or current, but
design constraints won't allow it. Will changing gears allow me to stay
in
the fat part of the motor's torque curve while continuing to accelerate
to
max speed, or should I just wring the motor out and accept whatever
output
it's capable of as current demand outstrips pack capacity?
--- End Message ---
--- Begin Message ---
> So do people usually go to only 50%DOD or all the way to 80%DOD?
If you want to get the most life out of your batteries, then 50% DoD is
the goal.
There are two reasons for this;
1) 50% DoD is less damaging to the battery so they last longer
2) If you spec your battery size so that they you have to do a 80% DoD to
get to your destination, once the battery capacity falls below 80% of
original spec, it will no longer reach your destination. With 50% you
have to wear the batteries out to the point where they drop below 50%
capcity befor you can no longer reach your destination.
The combination of these two points means that a battery drained daily to
80% might last a bit over a year, whereas the one only drained to 50%
might last three to five years.
>
> If I spec a battery at 100Ah 20hr rate (could someone explain the C's
> discharge measurement?) I need to subtract 40% to approximate the
> 1hr/1C
C=Capacity. If the battery has a rated capacity of 100Ah, then 1C equals
a 100 amp discharge. Most PbA batteries capacity is rated at the 20 hr
discharge rate, so our 100 AH battery is actually only food for 100 Ah if
you drain it at 5 Amps for 20 hours (C20 or 0.05C)
If the number is in front of the C then it means how many times the rated
capacity, i.e. 2C would be 200 amps, if the number is behind the C then it
means the AH rating divided by this number.
The 0.05C is an uncommon use of the term, most people would use the C20
instead. Normally only numbers >=1 are used in front of the C
>
>>Roughly speeking you will need 40% more capacity at the 20hr rate to
>> equal
>>the 1hr rate.
>
> so that leaves 60Ah and if I only drain it to 80% that leaves 48Ah of
> usable capacity.... correct?
> And 48ah x 312v = 14976w ~ 15kwh
>
>>Count for 4-5 miles range per each 1 kWh on board of good tuned EV.
>
> 15kwh x 4 = 60. So with 26 100ah batteries at 80%DOD we get an
> approximate 60mile range.
> Comments....?
Yup, true. and if you do this one a daily basis you can expect a battery
life of perhaps 1.5 years, if you're lucky.
>
> --
> TEhben
> 'hElix EV'
> evalbum: http://www.austinev.org/evalbum/1225
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
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--- Begin Message ---
Best of luck to you, let us know how it works out.
> Hi,
> I'm building a hybrid electic car and am interested in getting in
> touch with other people that have started or completed similar
> projects.
>
> Does anyone have the email address of this guy:
> http://www.teamswift.net/viewtopic.php?t=29720&highlight=
> (I registered on the site but the admins there have not blessed my
> request)
>
> For anyone who's interested, I post weekly updates of my progress here:
> http://www.gassavers.org/showthread.php?t=3070
>
> and occasionally on my own site:
> http://www.GreenPlanetGarage.com
>
> Best Regards,
> Tom.
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
Peter,
I must have missed your post about testing the Altairnano
cells. This is the first I have heard of them being released to
anyone for testing that was at liberty to reveal the actual results.
What sort o specific power do they have? What is their
specific energy?
They claim more than 4000 W/kg, but I haven't heard of
anyone confirming this. Are you seeing these numbers?
Bill Dube'
At 10:22 PM 6/26/2007, you wrote:
I did the math, after we cycled their cells. The math says their
claims hold up pretty well. Please ignore the man behind the curtain
holding a suitcase full of money. ;)
Keep in mind that Alairnano has not released any cells to anyone
outside their direct influence. If you have a hot new battery that
really works well, you want to make engineering development samples
available to all the OEMs. Altairnano has not done this. You do the math. :-)
Bill Dube'
--
www.electric-lemon.com
--- End Message ---
--- Begin Message ---
> I think I understand now. Regardless of pack voltage and gearing, when I
> demand acceleration the system has to generate X watts. Once the limits of
> pack voltage are reached, X watts are achieved by increasing amperage.
> Right?
Correct.
> When I look around, though, there doesn't seem to be a one-size-fits-all
> solution for every application.
Absolutely, there is no solution that fits every problem. Vehicles,
especially EVs are a compromise. Do we want better handling or more
comfort? Lower weight and drag or more interior space?
Multispeed transmission, or more batteries?
> Most of the respondents here have suggested that direct drive is the way
> to go.
with a motorcycle? Abolutely. The trade off is that without a multispeed
transmission, the motor has to develope more torque and/or RPM to give the
same performance.
With a car this means larger or more motors and more powerful controllers.
It means the same thing with a motorcycle, however motorcycles are
smaller to begin with so using a normal car size motor/controller already
gives you the needed torque advantage.
>That may be true, but I'm curious whether that's the general consensus
Almost all of the successful drag racing bikes forgo a transmission, this
is because of experience as much as theory.
> when pack voltage is limited to, say, 120 V due to packaging/range
> constraints. If, for example, I hold the motor at 9000 rpm to maintain top
> speed, it seems that I would be drawing big amps while unnecessarily
> decreasing motor life-expectancy due to centrifugal force (with most
> motors). Or I could change gear ratios and still demand the same wattage,
> but at a lower motor rpm. True?
Cumulative centifugal force seems to have very little effect on motor life
expectancy. As long as the motor is rated to handle the RPMs, then it
will continue to do so long past the time the motorcyle is scrap.
Gear it so it can reach your maximum designed speed while not quite
reaching your maximum RPM. THen look at what kind of torque it can
produce and see if that will meet your goals. If not, get a more powerful
motor/controller.
Another possiblity is to figure out how to build a small, litewieght two
speed transmission.
>
> I know it seems unrealistic to think that an operator might hold rpms at
> 9000 for any length of time, but if I'm going to start manufacturing
> motorcycles in any volume, I have to condsider every possibility.
Well, quite frankly, any motorcycle that can meet your designed speed
won't be able to do it for long unless you are spending a fortune on LiPol
batteries. At which point not many people will be willing to fork out the
cash needed anyway, so the number of people abusing the bike will also be
pretty small.
The power requirements to simply maintain 60 mph are fairly large on a
bike. Something like 5 or 6kw. If you are using Lead-Acid batteries
you'd be lucky to get 2kwh onboard, that means a range of maybe 15 miles,
or a 7.5 mile radius.
LiPol will give you much more range, perhaps 4 or 5 times as much. But
will cost a lot.
You are focusing on the motor and that is the least of your problems.
> Lon Hull,
> Portland, OR
>
>>
>> On 6/26/07, Loni <[EMAIL PROTECTED]> wrote:
>>>Of course I'd love to just dump in more voltage or current, but
>>> design constraints won't allow it. Will changing gears allow me to stay
>>> in
>>> the fat part of the motor's torque curve while continuing to accelerate
>>> to
>>> max speed, or should I just wring the motor out and accept whatever
>>> output
>>> it's capable of as current demand outstrips pack capacity?
>>
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
Christopher,
Hi, my name is Jim. I am an ASE master mechanic and
have been toying with the A/C requirements of my own
EV. The direct drive is an OK idea, but the automotive
compressors have the electromechanical clutches on
them for a reason. They are made to "cycle"
frequently under normal operating conditions. Without
this "cycling" of the compressor, the system will not
operate as it was designed to do. Start you ICE
vehicle, turn on the A/C and hold the engine RPM up at
2000 like your going down the road. No watch how
often the compressor cycles. This action should be
duplicated using your direct drive. And if it is
duplicated, I would think the life of your DC
accessory motor will be short. I have been looking
into the possibility of using the compressor from a
wrecked Toyota Prius. They use a "compressor/motor"
assembly. There are no external moving parts. Just
feed it power. But I'm still investigating what the
power requirements are for these compressors. If you
want to use the compressor you have, I would use belt
or chain drive and let the compressors clutch do it's
job. Have fun!!
Jim
--- Christopher Robison <[EMAIL PROTECTED]> wrote:
> On Wed, 2007-06-27 at 13:04 -0700, Alan Brinkman
> wrote:
> > Christopher,
> >
> > I wrote this huge reply to your message and
> deleted it and here are the
> > key points I can add. I have trouble creating
> short messages.
> >
>
> Thanks for the effort Alan, I really appreciate it.
> I'm going to fiddle
> around with the compressor and see what I can do
> with it, and I'll refer
> back to your email and Roland's and see if I
> understand more once I have
> the parts in front of me. I'm hoping to do
> something like what you're
> talking about, attaching to the front face of the
> clutch/pulley
> assembly, and using the bolt into the shaft end to
> center everything.
> Balancing might be an issue especially if I weld,
> but we'll see how it
> goes...
>
>
> --
> Christopher Robison
> [EMAIL PROTECTED]
> http://ohmbre.org <-- 1999 Isuzu Hombre +
> Z2K + Warp13!
>
>
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--- Begin Message ---
Following similar logic I have arrived at this design:
http://www.austinev.org/evalbum/preview.php?vid=1231
Hopefully I will get the 15 mi range at a reasonable DOD. I won't be
going over 50MPH often or for long stretches. Need to get it on the
licensed and on the road and find out. me
On 6/27/07, Peter VanDerWal <[EMAIL PROTECTED]> wrote:
> I think I understand now. Regardless of pack voltage and gearing, when I
> demand acceleration the system has to generate X watts. Once the limits of
> pack voltage are reached, X watts are achieved by increasing amperage.
> Right?
Correct.
> When I look around, though, there doesn't seem to be a one-size-fits-all
> solution for every application.
Absolutely, there is no solution that fits every problem. Vehicles,
especially EVs are a compromise. Do we want better handling or more
comfort? Lower weight and drag or more interior space?
Multispeed transmission, or more batteries?
> Most of the respondents here have suggested that direct drive is the way
> to go.
with a motorcycle? Abolutely. The trade off is that without a multispeed
transmission, the motor has to develope more torque and/or RPM to give the
same performance.
With a car this means larger or more motors and more powerful controllers.
It means the same thing with a motorcycle, however motorcycles are
smaller to begin with so using a normal car size motor/controller already
gives you the needed torque advantage.
>That may be true, but I'm curious whether that's the general consensus
Almost all of the successful drag racing bikes forgo a transmission, this
is because of experience as much as theory.
> when pack voltage is limited to, say, 120 V due to packaging/range
> constraints. If, for example, I hold the motor at 9000 rpm to maintain top
> speed, it seems that I would be drawing big amps while unnecessarily
> decreasing motor life-expectancy due to centrifugal force (with most
> motors). Or I could change gear ratios and still demand the same wattage,
> but at a lower motor rpm. True?
Cumulative centifugal force seems to have very little effect on motor life
expectancy. As long as the motor is rated to handle the RPMs, then it
will continue to do so long past the time the motorcyle is scrap.
Gear it so it can reach your maximum designed speed while not quite
reaching your maximum RPM. THen look at what kind of torque it can
produce and see if that will meet your goals. If not, get a more powerful
motor/controller.
Another possiblity is to figure out how to build a small, litewieght two
speed transmission.
>
> I know it seems unrealistic to think that an operator might hold rpms at
> 9000 for any length of time, but if I'm going to start manufacturing
> motorcycles in any volume, I have to condsider every possibility.
Well, quite frankly, any motorcycle that can meet your designed speed
won't be able to do it for long unless you are spending a fortune on LiPol
batteries. At which point not many people will be willing to fork out the
cash needed anyway, so the number of people abusing the bike will also be
pretty small.
The power requirements to simply maintain 60 mph are fairly large on a
bike. Something like 5 or 6kw. If you are using Lead-Acid batteries
you'd be lucky to get 2kwh onboard, that means a range of maybe 15 miles,
or a 7.5 mile radius.
LiPol will give you much more range, perhaps 4 or 5 times as much. But
will cost a lot.
You are focusing on the motor and that is the least of your problems.
> Lon Hull,
> Portland, OR
>
>>
>> On 6/26/07, Loni <[EMAIL PROTECTED]> wrote:
>>>Of course I'd love to just dump in more voltage or current, but
>>> design constraints won't allow it. Will changing gears allow me to stay
>>> in
>>> the fat part of the motor's torque curve while continuing to accelerate
>>> to
>>> max speed, or should I just wring the motor out and accept whatever
>>> output
>>> it's capable of as current demand outstrips pack capacity?
>>
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
Hi Ben,
I'll check on that for you. Did the new donor vehicle
have a manual trans to begin with? Or was it
automatic that you want to become manual.
Jim
--- [EMAIL PROTECTED] wrote:
> Anyone have experience.
> Moving the transmission with motor etc. from an 84
> S10 into a 93 S10.
> Should everything line up?
>
> The car I'm looking at buying has had the
> transmission removed (thus a
> great $ deal for a new glider) I believe the
> transmission I am using is
> from Brian Matthney's 87 S10 which he moved to the
> 84 S10, because Bob Rice
> said the 84 he gave Brian didn't have a
> transmission.
>
> Thanks, Ben
>
>
>
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--- Begin Message ---
Yes I will probably will not bother with trying to make this as it don't
sound promising at this time.. Yet It
Does sound interesting..
So nobody said anything about submerging the switching in mineral oil.. What
they thought that might do..
I thought about it and .. I was wondering how a D C arch would act in a
complete vacuum.. If that would minimize it.??
Mitchell
-------Original Message-------
From: Peter VanDerWal
Date: 6/25/2007 10:49:21 PM
To: ev@listproc.sjsu.edu
Subject: Re: Controler
That is actually a good question.
I'm going to try to simplify the answer a bit.
Let's consider a PMDC motor, it has magnets for the field and a wound
Rotor with brushes & comutators to bring the electricity to the rotating
Coils. Lots of coils and lots of commutator segments. The current in
Different coils will be at different states at different points in the
Rotation. The current will go from flowing in one direction to flowing in
The other and at some point in the rotation the current will be at zero,
This is where we have the brushes set so that the segment is at zero
Current when leaving the brush.
It's important to understand that motors and generators are exactly the
Same thing. If you pass a coil through a magnetic field, it generates an
Electrical current. If we pass electricity through a coil while it's
Sitting in a magnetic field, it generates movement.
Here is the key, when we pass current through the coil of a motor and it
Starts to move, it acts just like a generator at the same time. The coil
Is moving through a magnetic field so it is ALSO generating electricity.
Because of the nature of magnetic fields, etc. This generated electrical
Current is OPPOSITE to the applied current. It basically tries to fight
The applied current, this is called "Back Electro Motive Force (BEMF)" and
it's what keeps motors from drawing huge currents all of the time.
Anyway, the way motors are designed the several segments are usually under
The brushes at the same time. The motor is setup so that the BEMF on
Segment that is just leaving the brush is almost the same as the applied
Voltage, effectively at that point in the rotation the coil connected to
That segment is not drawing any current. The coil with it's segment near
The middle of the brush is, however, drawing current, and this keeps the
Motor turning.
So basically the design of the motor has it so that the segment leaving
The brush has already turned off it's current due to the ballanced BEMF
And applied voltage.
No current, no arc.
Of course the exact point where this happens changes depending on the
Applied current and speed of rotation. The choosen spot is usually not
Perfect so under some circumstances you will end up with a little brush
Arcing. Increasing the current, or the voltage, can make this arcing
Worse and many people have melted/burned their brushes. Especially the
Drag racers since they are always pushing their motors past the limits.
THis is why they talk about advancing brushes for drag racing etc,
Advancing the brushes makes them arc less under high currents, but
Somewhat more at low currents, howeve at low currents you see less damage
And drag racers mostly use high current anyway.
> Ok .. I got a stupid question.. I got the welder point a few times now and
> have been thinking about it .. Why don't out eclectic motors brushes weld
> and melt when we run our E Vs??/
>
> And what ever the reason is that they don't.. Why can not that be the same
> kind of contact for a switch?
> Mitchell
>
> -------Original Message-------
>
> From: Andre' Blanchard
> Date: 06/25/07 19:43:30
> To: ev@listproc.sjsu.edu
> Subject: Re: Controler
>
> At 05:17 PM 6/25/2007, you wrote:
>>If you want to build a mechanically driven drum switch circuits for motor
>>controller, it is best to get a early addition copy of The Standard
> Handbook
>>for Electrical Engineers from the year 1933 or so.
>>
>>You will not be able to down load this handbook, but you may luck out and
>>get a copy from the public library. The new later handbooks will set you
>>back more than a cost of a controller and they are not that detail.
>>
>>It has complete design section on any type of controller you want to
>> build.
>
>>There even sections on how to different type of batteries are made, how
>>motors are made and different winding configurations.
>>
>>With this handbook, all you need is a shop with machine tools, the raw
>>material, and it will show you how in detail to design and build any
>>electronic and electrical systems.
>>
>>Roland
>
> I did not find the entire books but I did find part of it.
>
> Section 13 from the Standard Handbook for Electrical Engineers 1908
> http://books.google.com/books?id=tkAFAAAAMAAJ
>
> Some other books
> http://books.google.com/books?id=SsIJAAAAIAAJ
> http://books.google.com/books?id=UOjpsFsWSrAC
> http://books.google.com/books?id=iDASAAAAIAAJ
> http://books.google.com/books?id=cgsAAAAAMAAJ
> http://books.google.com/books?id=UP8HAAAAMAAJ
> http://books.google.com/books?id=P_m7webHng8C
> http://books.google.com/books?id=5WGfE9UR_AEC
> http://books.google.com/books?id=ZlCLIxkECvwC
>
> __________
> Andre' B. Clear Lake, Wi.
>
>
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
Yesterday, I visited the unbelievably good technology and science
museum (Deutsches Museum) in Munich, Germany. It was a major treat to
see the first German U-boat, the U1 on display:
http://www.deutsches-museum.de/en/sammlungen/verkehr/maritime-exhibition/u1/
What I found particularly amusing is that they had
mechanically-adjustable brush timing on the electric propulsion
motors. There are hand wheels that worked threaded actuators to move
the brush rigging. The range of movement looked very broad, perhaps
20 degrees or more. Here is a picture showing the details of this
1906 state-of-the-art brush advance system.
http://www.killacycle.com/photos/misc/DSCN1903.JPG
100 years later and we are still using the same stuff. :-)
Bill Dube'
--- End Message ---
--- Begin Message ---
I just got this idea and it probably won't work!
How about I take 4 36 volt DeWalt battery packs and use them in an
electric car!Then, I'll program the charger not to charge them all the
way to 100%. I'll need to either have a battery balancer or tend to
each cell to make sure that they are balanced.
Can someone please point out to me why this won't work?
--- End Message ---
--- Begin Message ---
My, my, how technology advances! (sarcastic)
On 6/28/07, Bill Dube <[EMAIL PROTECTED]> wrote:
Yesterday, I visited the unbelievably good technology and science
museum (Deutsches Museum) in Munich, Germany. It was a major treat to
see the first German U-boat, the U1 on display:
http://www.deutsches-museum.de/en/sammlungen/verkehr/maritime-exhibition/u1/
What I found particularly amusing is that they had
mechanically-adjustable brush timing on the electric propulsion
motors. There are hand wheels that worked threaded actuators to move
the brush rigging. The range of movement looked very broad, perhaps
20 degrees or more. Here is a picture showing the details of this
1906 state-of-the-art brush advance system.
http://www.killacycle.com/photos/misc/DSCN1903.JPG
100 years later and we are still using the same stuff. :-)
Bill Dube'
--- End Message ---
