EV Digest 4133
Topics covered in this issue include:
1) RE: GTech Performance meter on an EV
by "Don Cameron" <[EMAIL PROTECTED]>
2) Re: 10 Tour de Sol Monte Carlo starting points ...
by "Dave" <[EMAIL PROTECTED]>
3) RE: Hygrometers, eq'ing, water cons., and 8 mo. floodies, revisited
by "Roger Stockton" <[EMAIL PROTECTED]>
4) Re: Current Capacity of 1/2" Copper Pipe
by Victor Tikhonov <[EMAIL PROTECTED]>
5) Re: 10 Tour de Sol Monte Carlo starting points ...
by M Bianchi <[EMAIL PROTECTED]>
6) Re: Current Capacity of 1/2" Copper Pipe
by Victor Tikhonov <[EMAIL PROTECTED]>
7) RE: Welding Aluminum Re: Battery Box Advice Sought
by "Chris Tromley" <[EMAIL PROTECTED]>
8) Re: Fwd: RE: Welding Aluminum Re: Battery Box Advice Sought
by Eric Poulsen <[EMAIL PROTECTED]>
9) RE: Welding Aluminum
by Reverend Gadget <[EMAIL PROTECTED]>
10) Re: Welding Aluminum
by Ryan Stotts <[EMAIL PROTECTED]>
11) RE: Current Capacity of 1/2" Copper Pipe
by "Don Cameron" <[EMAIL PROTECTED]>
12) Re: Question: Max efficiency charging with 3 phase alternator
by "David Chapman" <[EMAIL PROTECTED]>
13) Re: 1500 dollar complete VW conversion.
by "Tom Shay" <[EMAIL PROTECTED]>
14) Re: charger
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
15) 3 phase alternator-why not an induction machine?
by "djsharpe" <[EMAIL PROTECTED]>
16) Re: Question: Max efficiency charging with 3 phase alternator
by Lee Hart <[EMAIL PROTECTED]>
17) Re: 3 phase alternator-why not an induction machine?
by "Peter VanDerWal" <[EMAIL PROTECTED]>
18) Re: 3 phase alternator-why not an induction machine?
by Victor Tikhonov <[EMAIL PROTECTED]>
19) Re: 3 phase alternator-why not an induction machine?
by Lee Hart <[EMAIL PROTECTED]>
20) Re: 1500 dollar complete VW conversion.
by Lee Hart <[EMAIL PROTECTED]>
21) Re: 3 phase alternator-why not an induction machine?
by Lee Hart <[EMAIL PROTECTED]>
22) Re: 3 phase alternator-why not an induction machine?
by "Peter VanDerWal" <[EMAIL PROTECTED]>
23) Re: 3 phase alternator-why not an induction machine?
by "Peter VanDerWal" <[EMAIL PROTECTED]>
24) Re: 3 phase alternator-why not an induction machine?
by Rod Hower <[EMAIL PROTECTED]>
--- Begin Message ---
The GTech Pro is a thing of beauty. Yes, it does determine the engine RPM
from the ignition noise in the 12V system. It works well at comparative
measurements with the same vehicle over time. Not a lot of use comparing HP
measurements with other cars, unless they use a GTech as well, as the unit
reports on HP at the wheel.
The PC software produces some real nice HP and Torque graphs, also tells you
when to shift.
It can store up to a hour of data.
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of [EMAIL PROTECTED]
Sent: February 28, 2005 10:57 AM
To: [email protected]
Subject: GTech Performance meter on an EV
http://www.gtechpro.com/prod.html
Do any of you NEDRA types have experience with the GTech Pro meter? It
seems to be a performance gauge that uses RF noise from an ignition system,
plus accelerometers to compute acceleration, torque, 0-60 times, shift
points, 1/4 mile times, etc.. You program the system with vehicle weight,
desired shift points, etc., but it has no sensors hardwired to the car. It
might be a fairly simple task to create the right noise to use this setup in
an EV. I'd be amazed if it could track accel/decel over a trip of any
length and still produce accurate speed measurements, but it might be useful
to answer those nagging performance questions we all get.
Just a stray idea,
Jay Donnaway
--- End Message ---
--- Begin Message ---
I guess a human body counts as an ICE...I should have been clearer, I guess!
The 200 cc/LPG hybrid is just what I was thinking. The limits would be top
speed/range, as it is in all cars. I was thinking a VW Diseasel, running on
cooking oil, with an electric boost/prt time motor.
David C. Wilker Jr. USAF (RET)
Children need love, especially when they do not deserve it.
- Harold S.
Hulbert
----- Original Message -----
From: "Evan Tuer" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Monday, February 28, 2005 11:03 AM
Subject: Re: 10 Tour de Sol Monte Carlo starting points ...
On Mon, 28 Feb 2005 10:08:14 -0800, Dave <[EMAIL PROTECTED]>
wrote:
Random thoughts...has anyone heard anything about hybrids combining
alternative (Bio diesel, LPG, CNG) fuels ICEs and electric motors? Just
curious. I am thinking of building a vehicle that has the cheapest cost
per
mile, period. NOT counting the initial construction cost.
How about a bicycle? What's the cost per mile when fuelled by Mars bars?
:)
I plan to use a 200cc 1-cylinder LPG fuelled engine in "parallel
hybrid" configuration to supplement the range in the EV I am building
now. It should be pretty cheap per mile.
--- End Message ---
--- Begin Message ---
Bob Bath [mailto:[EMAIL PROTECTED] wrote:
> I pretty much pull 2-4 kWh out of the batteries
> each day and charge the 144V pack each night to 186V,
> and hold it there for 15 mins.
> Every 2-3 weeks, I take it to 186V and hold it
> there for 1-2 hours.
You are almost certainly not charging enough. 186V/72 cells is
2.583V/cell, which is US Battery's recommendation... at a temperature of
about 26.7C/80F. You note that it has been chilly lately, which makes
me suspect you should be charging to a higher voltage
(+0.005V/cell/degree C, or +0.36V/degree C for the 144V string).
Also, once you reach the target voltage, you need to hold that until the
current tapers to a few percent of the rated Ah capacity (e.g. about
3A), not 15min or 1-2hr. By the time the charger shuts off you want to
have returned about 110% of the Ah that were removed. If you set the
timer for a longish period (e.g. 4-5hr) and monitor the current, you can
determine how long it must be set to in order that the current tapers to
3A.
You can also determine how much longer you need to let the charger run
in order that 110% of the Ah removed are returned (watch your E-Meter,
and beware that it will reset the Ah display then it thinks the charged
parameters are met, so that even though it counts upwards after that,
there may be a few Ah 'missing'; e.g. you discharge to -100Ah, then
recharge. At -5Ah the Emeter resets to 0. At the end of charge you see
+20; this means 125Ah or 125% of the Ah removed have been returned, not
120Ah/120% as you would first think). Oh, and the E-Meter also
'discounts' charge Ah by the CEF, so unless you have set it to 0.99, you
need to take that into account also (e.g. CEF=0.90 means that every Ah
put back into the pack is only counted as 0.9Ah by the E-meter, so by
the time it indicates 100Ah returned, you have actually returned 111Ah).
> The thing is, you don't hold it there for _time_,
> you hold it there until the specific gravity is 1.265,
> plus/minus a bit depending on temp.
Actually, you want the specific gravity higher than that on traction
batteries.
For ~most~ floodeds, you can charge until the voltage stops rising and
be fairly confident that the specific gravity has also risen as high as
it is going to. You ought to see temperature compensated specific
gravities around 1.290 (or 1.300 for relatively new, healthy batteries).
> I remember my alternative propulsion class at a JC,
> where we used this really cool white gizmo that you
> put a drop on, and get a MAJOR accurate reading.
> Who makes them?
> Where do you get them?
Sounds like a refractometer. The one I use is made by MISCO. It has
scales to measure antifreeze (ethylene glycol) strength also, and if you
plan to use this feature you can get the device with either Celsius or
Fahrenheit scales. It is pricey (US$149), but very convenient to use
and you have to go to 10x the cost laboratory instruments to get better
resolution (0.005) or precision (+/-0.005).
<http://www.misco.com/products/7084VP%2B.html>
<http://www.process-controls.com/Metex/Misco/7064VP.htm>
I've tried the typical float type refractometer as well as the E-Z-RED
pointer type and find the refractometer much more convenient and
repeatable to use. It is easy to read and there is no ambiguity about
the value indicated or dependence upon the device being held precisely
in a certain orientation.
The only problem I've had is that some new batteries can have a black
tarry contaminant in the electrolyte for the first several cycles (the
manufacturer explains that this is mold release, etc. from the
manufacturing process) that can interfere with the refractometer
reading. The symptom is that instead of the crisp light/dark line one
normally sees in the eyepiece, the upper portion of the scale is only
very slightly dimmer than the lower half instead of being dark. The
solution is to use a bit of isopropyl alcohol to clean the window upon
which the electrolye sample is placed and repeat the reading.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Don Cameron wrote:
> I estimate absolute max amperage draw of my 312V system will be 300Amps.
It is more like 200A max out of (and into) the battery, unless you are
on the Woodburn race track...
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
> From: David Dymaxion <[EMAIL PROTECTED]>
> Is there a category for electric vehicles?
>
> Categories
> 1- Toyota Prius Classic (2001-2003)
> 2- Toyota Prius (2004-2005)
> 3- Honda Insight
> 4- Honda Civic Hybrid
> 5- Honda Accord Hybrid
> 6- Hybrid SUV - Ford Hybrid Escape, Toyota Highlander Hybrid,
> Lexus 400 Hybrid.
> 7- Custom Built hybrids (modified or built from scratch)
> 8- Modified Factory Hybrids, including plug-in factory hybrids
> 9- Biodiesel, and clean diesel vehicles
Those are the categories for the Monte Carlo Rally. If you have an EV that can
drive any of the routes in competition with the others, by all means!
Seriously, the EVs are entered in the Tour de Sol Championship. See ...
http://www.nesea.org/transportation/tour/2005championship.html
--
Mike Bianchi
17th Annual Tour de Sol
May 13-16, 2005 in Saratoga and Albany, NY
Featuring New Events, Competitions, Activities Leading the Way to a
Sustainable Energy and Transportation Future, A Green "Car Show" and More
www.TourDeSol.org
www.Foveal.com/Tour_de_Sol_Reports.html
--- End Message ---
--- Begin Message ---
Don,
Did you use noalox or any other anticorrosion compound before crimping?
http://www.metricmind.com/ac_honda/images/strap2.jpg
Before crimp
http://www.metricmind.com/ac_honda/images/strap4.jpg
After the crimp - extra noalox is squeezed out
http://www.metricmind.com/ac_honda/images/strap5.jpg
End result
http://www.metricmind.com/ac_honda/images/strap7.jpg
Nave no problems with my interconnects since day one.
Victor
'91 ACRX - something difrferent
Don Cameron wrote:
Dave, I am on a newer version this evening.
I used a home made solder pot (before reading Lee's warning) to tin the
copper tubes before inserting the straps (all the way through). Then I
crimped the tubes onto the braided straps with a vice and drilled a hole. I
experimented with dipping them in the solder pot again, but this caused the
braid to become rigid (which defeats the purpose). So in the current
version, there is some exposed copper.
I will leave it to others to comment about NiCd, copper and corrosion.
Here is a picture of all the straps/cables I have tried.
a) the flattened copper tube,
b) the tubes with a braid and no tinning
c) Tin, crimp then tin again (but causes the braid to stiffen)
d) Tin, then crimp (Current version)
e) The last is the 2/0 cable I tested for Ryan.
www.cameronsoftware.com/ev/images/VariousBatteryCables.JPG
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Dave Cover
Sent: February 26, 2005 7:22 PM
To: EVList
Subject: RE: Current Capacity of 1/2" Copper Pipe
--- Don Cameron <[EMAIL PROTECTED]> wrote:
Here is what I have come up with:
http://www.cameronsoftware.com/ev/images/BatteryStraps.JPG
Since I cannot find any connectors commercially available (locally
anyways) with 1/4" stud, I used Victor's suggestion of braided cable
with crimped copper pipe on either end. The braid goes through the
entire pipe, so when they are bolted to the batteries this will ensure
a good solid connection, but still allow flex.
Will there be any corrosion issues using this method with NiCad batteries?
Is there an easy way to coat/tin/protect the ends to prevent corrosion?
Also, do NiCads have issues with corroding the battery enclosure like lead
acids do from venting?
Thanks
Dave Cover
--- End Message ---
--- Begin Message ---
Dave Cover wrote:
> --- Chris Tromley <[EMAIL PROTECTED]> wrote:
> >
> > If you must rivet two different metals together, sealing the joint
> > will also dramatically reduce galvanic corrosion. Consider
> it a must
> > if you're joining an aluminum battery rack to a steel body.
> Make it
> > absolutely waterproof anywhere the two metals are in contact.
>
> Could you use a rubber gasket that would provide a waterproof
> seal and prevent most of the contact between the metals? How
> about first treating the aluminum box with a coating like
> spray on bed liner?
Hi Dave,
You don't want anything compliant in a joint. Compliance allows movement,
which encourages the rivets to work loose. Leave the original paint if it's
thin (it will act as a semi-solid seal) and pull everything up tight, metal
to metal. Then squirt your sealant over the outside of the joint surfaces.
Rubberized undercoating is messy, but it gets into crevices very well and
can be removed if necessary with light scraping or mineral spirits.
Make sure you cover all the rivet heads. Don't forget the back side of the
joint. Everywhere the body, rack and/or rivet are dissimilar must be
thoroughly sealed. Sealing "most of the contact" isn't enough - wherever
the couple is exposed will corrode. If you can't reach the deformed end of
a rivet, dip it in sealant or rust-preventative paint before inserting and
setting it.
Reverend Gadget wrote:
> Also when joining steel and aluminum, I find it best
> to use stainless steel. It's a better rivet, and will
> last longer than an aluminum one.
SS is certainly stronger than aluminum and is far more compatible
galvanically with aluminum. But it's a bad match with plain steel. When
steel and SS are paired the steel corrodes aggressively. SS can also be
weaker than steel depending on the alloy, treatment, etc. Personally I'd
stay with two dissimilar metals in a joint rather than three, unless the
specific application dictated otherwise. So I'd probably pick steel rivets
to attach aluminum racks to a steel body. And then seal it for longevity.
Chris
--- End Message ---
--- Begin Message ---
These guys do welding of aluminum for aircraft frames using an
oxy/acetylene setup. Specifically, they sell the equipment and know-how:
http://tinmantech.com/html/aluminum_gas_welding__brazing_.html
Dave Cover wrote:
--- Chris Tromley <[EMAIL PROTECTED]> wrote:
If you must rivet two different metals together, sealing the joint will also
dramatically reduce galvanic corrosion. Consider it a must if you're
joining an aluminum battery rack to a steel body. Make it absolutely
waterproof anywhere the two metals are in contact.
Could you use a rubber gasket that would provide a waterproof seal and
prevent most of the contact
between the metals? How about first treating the aluminum box with a coating
like spray on bed
liner?
Dave Cover
--- End Message ---
--- Begin Message ---
If you can get a good contact area, 3M makes
structural tape. This stuff is especially good when
connecting aluminum to steel as it will isolate the
two materials. This stuff is amazing. It is used to
apply the body panels on some of the newer buses and I
saw some holding the panels on the Getty Center.
Gadget
--- Peter VanDerWal <[EMAIL PROTECTED]> wrote:
> Any recommendations for/against chemically bonding
> aluminum (i.e. glue)?
>
> Why is a good adhesive for aluminum to aluminum
> bonds?
> Aluminum to steel?
>
> Thanks.
>
>
=====
visit my website at www.reverendgadget.com
--- End Message ---
--- Begin Message ---
On Mon, 28 Feb 2005 12:15:06 -0700 (MST), Peter VanDerWal
<[EMAIL PROTECTED]> wrote:
> Any recommendations for/against chemically bonding aluminum (i.e. glue)?
>
Have a look at this stuff:
http://www.eastwoodco.com/shopping/product/detailmain.jsp?itemID=1222&itemType=PRODUCT&iMainCat=483&iSubCat=487&iProductID=1222
--- End Message ---
--- Begin Message ---
Yes, I did, but thanks for the reminder, I will put this in my notes on the
web site.
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Victor Tikhonov
Sent: February 28, 2005 12:08 PM
To: [email protected]
Subject: Re: Current Capacity of 1/2" Copper Pipe
Don,
Did you use noalox or any other anticorrosion compound before crimping?
http://www.metricmind.com/ac_honda/images/strap2.jpg
Before crimp
http://www.metricmind.com/ac_honda/images/strap4.jpg
After the crimp - extra noalox is squeezed out
http://www.metricmind.com/ac_honda/images/strap5.jpg
End result
http://www.metricmind.com/ac_honda/images/strap7.jpg
Nave no problems with my interconnects since day one.
Victor
'91 ACRX - something difrferent
Don Cameron wrote:
> Dave, I am on a newer version this evening.
>
> I used a home made solder pot (before reading Lee's warning) to tin
> the copper tubes before inserting the straps (all the way through).
> Then I crimped the tubes onto the braided straps with a vice and
> drilled a hole. I experimented with dipping them in the solder pot
> again, but this caused the braid to become rigid (which defeats the
> purpose). So in the current version, there is some exposed copper.
>
> I will leave it to others to comment about NiCd, copper and corrosion.
>
> Here is a picture of all the straps/cables I have tried.
> a) the flattened copper tube,
> b) the tubes with a braid and no tinning
> c) Tin, crimp then tin again (but causes the braid to stiffen)
> d) Tin, then crimp (Current version)
> e) The last is the 2/0 cable I tested for Ryan.
>
>
> www.cameronsoftware.com/ev/images/VariousBatteryCables.JPG
>
> Don
>
>
>
>
>
> Victoria, BC, Canada
>
> See the New Beetle EV Conversion Web Site at
> www.cameronsoftware.com/ev/
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
> On Behalf Of Dave Cover
> Sent: February 26, 2005 7:22 PM
> To: EVList
> Subject: RE: Current Capacity of 1/2" Copper Pipe
>
> --- Don Cameron <[EMAIL PROTECTED]> wrote:
>
>>Here is what I have come up with:
>>http://www.cameronsoftware.com/ev/images/BatteryStraps.JPG
>>
>>Since I cannot find any connectors commercially available (locally
>>anyways) with 1/4" stud, I used Victor's suggestion of braided cable
>>with crimped copper pipe on either end. The braid goes through the
>>entire pipe, so when they are bolted to the batteries this will ensure
>>a good solid connection, but still allow flex.
>
>
> Will there be any corrosion issues using this method with NiCad batteries?
> Is there an easy way to coat/tin/protect the ends to prevent corrosion?
>
> Also, do NiCads have issues with corroding the battery enclosure like
> lead acids do from venting?
>
> Thanks
>
> Dave Cover
--- End Message ---
--- Begin Message ---
Are Selenium rectifiers any good for this type of thing? I think that is
what I have, lots of flat plates in a stack with spacers between and lugs
off the ends? A number of them the size of your fist, I even have one that
is like 2 feet long X 10" X 10" square. Been trying to find a use for them.
David Chapman
Arizona Electropulsion / Fine-Junque
http://stores.ebay.com/theworldoffinejunque
----- Original Message -----
From: "Peter VanDerWal" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, February 27, 2005 12:08 PM
Subject: Re: Question: Max efficiency charging with 3 phase alternator
Peter VanDerWal wrote:
Looking for some ideas on how to Maximize efficiency when using
a 3-phase PM alternator to charge batteries. 30V nominal battery
voltage.
Simplest way would probably be to use a 6-way bridge. I know I'll
lose about 2% in the diodes
Lots more than that! The diodes have about a 1v drop at rated current,
and there are two in series. 2v/30v = 7% lost to the diodes.
At 30v, you can easily cut this in half with schottky diodes (3.5%). You
could cut this loss in half again with synchronous rectification
(complicated) or germanium diodes (hard to find).
Should have mentined that I was planning on using Schottky's, I forgot
about having two in series though.
how much will I lose do to power factor issues?
That's harder to estimate. With a simple 3-phase rectifier bridge, the
alternator coils see about a 0.7 power factor. Improving this to 1.0
basically reduces the winding current to 70% for the same power output.
You'd have to know the winding resistance to estimate what your I^2R
losses are now, and what 70% less current would reduce them to. Then,
add the losses of whatever circuit you use for power factor correction.
Ok so PFC will only get me another 1 or 2%.
Can I use the same FETs for synch rectification and PFC?
FWIW I was thinking about using one of the Ecycle motors as a generator
(roughly 95% efficient) so if I did and went with a 6 way schottky
rectifier I'd be down to about 91%, about the same as a similar sized Etek
and I believe slightly cheaper.
Ecycle's CMG series alreay has sychronous rectification built in. Though
I don't think it's controllable.
If I can get a a controller that offers synch rect, PFC, and is
controllable for output power (or what I want: input load, same thing), it
might have a slight edge on a Lynch/Etek with similar controller, plus no
worries about brushes, and it's a (more or less) sealed unit.
--- End Message ---
--- Begin Message ---
Yes, the VW conversion kit is interesting. But, it would perform very
poorly.
The motor is too small to drive a VW even with the drive reduction
provided by the belt drive. The motor looks suspiciously like an
old Ford automobile starter. These starters were often used for
driving a variety of things because they had a long straight shaft
that could be fitted with a pulley, sprocket, etc.. They had small
brushes and commutators and sleeve
bearings suitable for intermittent use like a starter but not for
continuous duty. The claims for horsepower, 15 continous and 40
intermittent are outrageous. At 36 volts, 15 hp requires at least 400
amps and 40 hp requires at least 1100. The little motor simply
couldn't handle such high currents.
To make a serious EV would require a motor like the ADC 8-inch
and at least a 96-volt battery pack. With a better motor the belt
drive could be dispensed with and the motor coupled directly
to the transmission input shaft.
Of more interest to me on tne web site are the hub motors.
----- Original Message -----
From: "Lawrence Rhodes" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, February 28, 2005 2:35 AM
Subject: 1500 dollar complete VW conversion.
These guys have some interesting concepts & a very inexpensive VW
conversion. A light kit body and a sub 2000 pound weight would be very
interesting. Looks like this kit could be completed in a weekend.
Anybody done one?
http://www.e-volks.com/index.html
Lawrence Rhodes
Bassoon/Contrabassoon
Reedmaker
Book 4/5 doubler
Electric Vehicle & Solar Power Advocate
[EMAIL PROTECTED]
415-821-3519
--- End Message ---
--- Begin Message ---
Stop charging. What batteries do you have? How many? Condition of the
batteries. Are they new? Old? Used? If they are 6v 7.75 per flooded
battery is about right. Multiply that by the number of 6v batteries and you
have your charge voltage. . Give us some numbers and we can help. Untill
then don't charge. LR.......
----- Original Message -----
From: "ohnojoe" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Monday, February 28, 2005 10:56 AM
Subject: charger
Hey,
I'm new to EVing and just got my first EV on the road. It has a K&W BC-20
charger with a line booster.
I put new batteries in the truck and tried to set the charger per the
instruction. However, the current gage did not drop to below 10 even
after
an 18 hour charge. (I used a volt meter and some jumper cables between the
most neg and most pos terminals 131.6 volts). I could hear the batteries
boiling and some on the electrolyte came out of the tops of some of the
batteries.
--- End Message ---
--- Begin Message ---
You could consider an induction motor run as a generator for higher
voltage systems instead of a synch alternator. All you need is a bank of
capacitors and to auto excite the machine and 6 diodes to rectify the
output. These machines are cheap but have slightly less efficiency than
a well designed alternator. You could supply batteries of about 120V and
up. Lower voltages will need a matching auto transformer. Induction mcs
have ideal characteristics to battery charge but must always have a
load. Loose your load and very high voltages are produced.
David
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of jerry dycus
Sent: Tuesday, 1 March 2005 12:58 AM
To: [email protected]
Subject: Re: Question: Max efficiency charging with 3 phase alternator
Hi Raymond and All,
--- Raymond Knight <[EMAIL PROTECTED]> wrote:
I assume you are talking about auto-truck
alternators as 3ph can be a good amount better than
that.
But they until higher voltages and larger sizes
won't be nearly as eff as a PM or shunt DC generators
especialy at lower voltages with eff of 85-93% or so.
Of course YMMV!
And I can almost garrantee that engineers are
not responseable for most problems, ineff of
auto-truck alts but accountants, corporate cost
cutters instead!
I use a surplus 70 amp PM motor at probably
85-88 % eff for my EV hybrid generator to get the max
from my engine as it's fairly small at 5.5 hp and
keeps it lightweight, under 75lbs.
An E-tek would be even more eff at 90% for him or
so, more costly than mine but for me won't go to 80-90
vdc I'll need for my next EV 72vdc nom batt pack.
For anyone wanting to charge batts or make a
hybrid a PM or shunts generator is a much better
choice and can be used to start the ICE and possibly
add acceleration power directly to the drive train as
a motor when needed.
I'll just use mine as a series sometimes hybrid,
range extender as it will be able to be taken off when
not needed.
HTH's
jerry dycus
> The most efficient commercial available units are
> only 74%. They can produce
> a ton of amperage, Ecoair is
> 240amps/12volts/1650shaft rpm, 310amps max. The
> Bosch is only 160amps max, don't know about its
> lower rpm, I think around
> 100amps. Ecoair is getting ready for production a
> 140amp/12volt/1650shaft
> rpm alternator as well. They can be factory adjusted
> to charge at up to
> 48volts, so you can get them preset at 30volts. They
> have temperature
> compensation and they use the bucking when the
> alternator is not needed. The
> Ecoair would probably be a 1300-1500 dollar
> adventure. The new model soon to
> be released will be half that? The Ecoair gets its
> efficiency from a coil
> wound and permanent magnet rotor assembly, the Bosch
> claims it is done with
> more efficient stator windings. I have never seen
> the Bosch up close so I
> can give you more specifics about it.
> The Denso on the newer Chryslers is using a square
> wire stator, and we are
> seeing very good turn on/bottom end amperages from
> it. How efficient it is I
> don't know. But since it is producing high rates at
> very low rpm and not
> burning up, I would think it is better than the
> normal 50%-55% of a claw
> pole alternator.
> And for the record on the other thread, I have
> either built or overseen the
> production/repair of over 25,000
> starters/alternators/DC motors in just the
> last 10years. AERAC was founded in my parents
> kitchen 20+ years ago, so I do
> know a little bit about them. :) I may not be an
> engineer, but I make my
> living correcting their mistakes. No offense
> intended to the engineering
> community with that.
>
>
__________________________________
Do you Yahoo!?
Yahoo! Mail - Find what you need with new enhanced search.
http://info.mail.yahoo.com/mail_250
--- End Message ---
--- Begin Message ---
David Chapman wrote:
> Are Selenium rectifiers any good for this type of thing?
They're ok as rectifiers -- just not very efficient.
Selenium rectifiers were popular until the 1960's because they were
cheap and easy to make. Each "diode" is basically a painted metal plate,
with about a 30v reverse breakdown voltage. The plates were stacked up
in series to get higher voltages.
Selenium rectifiers act more like resistors than diodes. Their forward
resistance is about 1/100th of their reverse resistance, so they work as
rectifiers. But their forward voltage drop gets rather high (1-3 volts
at rated current), and their reverse leakage current (many milliamps)
makes them get hot. They are also quite sensitive to heat; thus their
big "cooling fin" like shape.
--
"The two most common elements in the universe
are hydrogen and stupidity." -- Harlan Ellison
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
I'm familiar with using induction motors as generators. FWIW, you can't
usually draw three phases off them at any significant current with out
collapsing the fields. Normally folks only use these for single phase
output.
At any rate, at the low power, low voltage levels that I'm looking for
(30V @ ~8 amps) the aren't really a viable candidate.
> You could consider an induction motor run as a generator for higher
> voltage systems instead of a synch alternator. All you need is a bank of
> capacitors and to auto excite the machine and 6 diodes to rectify the
> output. These machines are cheap but have slightly less efficiency than
> a well designed alternator. You could supply batteries of about 120V and
> up. Lower voltages will need a matching auto transformer. Induction mcs
> have ideal characteristics to battery charge but must always have a
> load. Loose your load and very high voltages are produced.
> David
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> Behalf Of jerry dycus
> Sent: Tuesday, 1 March 2005 12:58 AM
> To: [email protected]
> Subject: Re: Question: Max efficiency charging with 3 phase alternator
>
> Hi Raymond and All,
> --- Raymond Knight <[EMAIL PROTECTED]> wrote:
>
> I assume you are talking about auto-truck
> alternators as 3ph can be a good amount better than
> that.
> But they until higher voltages and larger sizes
> won't be nearly as eff as a PM or shunt DC generators
> especialy at lower voltages with eff of 85-93% or so.
> Of course YMMV!
> And I can almost garrantee that engineers are
> not responseable for most problems, ineff of
> auto-truck alts but accountants, corporate cost
> cutters instead!
> I use a surplus 70 amp PM motor at probably
> 85-88 % eff for my EV hybrid generator to get the max
> from my engine as it's fairly small at 5.5 hp and
> keeps it lightweight, under 75lbs.
> An E-tek would be even more eff at 90% for him or
> so, more costly than mine but for me won't go to 80-90
> vdc I'll need for my next EV 72vdc nom batt pack.
> For anyone wanting to charge batts or make a
> hybrid a PM or shunts generator is a much better
> choice and can be used to start the ICE and possibly
> add acceleration power directly to the drive train as
> a motor when needed.
> I'll just use mine as a series sometimes hybrid,
> range extender as it will be able to be taken off when
> not needed.
> HTH's
> jerry dycus
>
>> The most efficient commercial available units are
>> only 74%. They can produce
>> a ton of amperage, Ecoair is
>> 240amps/12volts/1650shaft rpm, 310amps max. The
>> Bosch is only 160amps max, don't know about its
>> lower rpm, I think around
>> 100amps. Ecoair is getting ready for production a
>> 140amp/12volt/1650shaft
>> rpm alternator as well. They can be factory adjusted
>> to charge at up to
>> 48volts, so you can get them preset at 30volts. They
>> have temperature
>> compensation and they use the bucking when the
>> alternator is not needed. The
>> Ecoair would probably be a 1300-1500 dollar
>> adventure. The new model soon to
>> be released will be half that? The Ecoair gets its
>> efficiency from a coil
>> wound and permanent magnet rotor assembly, the Bosch
>> claims it is done with
>> more efficient stator windings. I have never seen
>> the Bosch up close so I
>> can give you more specifics about it.
>> The Denso on the newer Chryslers is using a square
>> wire stator, and we are
>> seeing very good turn on/bottom end amperages from
>> it. How efficient it is I
>> don't know. But since it is producing high rates at
>> very low rpm and not
>> burning up, I would think it is better than the
>> normal 50%-55% of a claw
>> pole alternator.
>> And for the record on the other thread, I have
>> either built or overseen the
>> production/repair of over 25,000
>> starters/alternators/DC motors in just the
>> last 10years. AERAC was founded in my parents
>> kitchen 20+ years ago, so I do
>> know a little bit about them. :) I may not be an
>> engineer, but I make my
>> living correcting their mistakes. No offense
>> intended to the engineering
>> community with that.
>>
>>
>
>
>
>
> __________________________________
> Do you Yahoo!?
> Yahoo! Mail - Find what you need with new enhanced search.
> http://info.mail.yahoo.com/mail_250
>
>
--- End Message ---
--- Begin Message ---
The key word here is "autoexcite", it will be very difficult
to do with simple means (for asynchronous machine).
What Peter wants is easily done with Siemens PM machines -
inverter running in constant regen mode which provides steady
(and adjustable/programmable) output regardless of RPM, driven
from and induction or synchronous PM machine. It is clean modern
way to do it, but expensive. 1FVxxxx series of motors to be used
primarily as a generators was developed for this purpose.
(BTW, quite powerful, see http://www.feys.org/System/our_system.htm )
BTW, PM motors are preferred to asynchronous ones for this type
of work because of efficiency. You don't spend energy to create
magnetic fields - they are already there from the PMs.
(not the only advantage, just one of them).
If Peter's gen is low voltage, and cost is the priority concern,
I'd use shottky rectifiers and live with remaining losses.
Is there a way to use higher voltage option Peter?
Victor
djsharpe wrote:
You could consider an induction motor run as a generator for higher
voltage systems instead of a synch alternator. All you need is a bank of
capacitors and to auto excite the machine and 6 diodes to rectify the
output. These machines are cheap but have slightly less efficiency than
a well designed alternator. You could supply batteries of about 120V and
up. Lower voltages will need a matching auto transformer. Induction mcs
have ideal characteristics to battery charge but must always have a
load. Loose your load and very high voltages are produced.
David
--- End Message ---
--- Begin Message ---
djsharpe wrote:
> You could consider an induction motor run as a generator for higher
> voltage systems instead of a synch alternator. All you need is a
> bank of capacitors and to auto excite the machine and 6 diodes to
> rectify the output. These machines are cheap but have slightly less
> efficiency than a well designed alternator.
Yes, this is a cheap and easy way to do it. Induction motors for 120vac
and up are easy to come by. More efficient than an automotive-type
alternator, but not as good as a high-efficiency one.
> Lower voltages will need a matching auto transformer.
That's one way to do it. You can also rewire the pole pairs in parallel
instead of series to alter the basic voltage. Or, since the voltage is
proportional to rpm, run it at a different speed to get the desired
voltage.
> must always have a load. Lose your load and very high voltages
> are produced.
The capacitors provide the necessary load. Induction generators only
work when they see a capacitive load. With the right capacitors it will
work fine with no load. The basic voltage is controlled by rpm, just
like a PM generator.
--
"The two most common elements in the universe
are hydrogen and stupidity." -- Harlan Ellison
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Tom Shay wrote:
> Yes, the VW conversion kit is interesting. But, it would perform
> very poorly.
Yes; they do talk about a 35 mph top speed, m0-mile range with 3 12v
batteries, or 20 miles with 6 golf cart batteries. These sound
relatively honest -- not the usual wild exaggerations we sometimes see.
> The motor is too small to drive a VW even with the drive reduction
> provided by the belt drive. The motor looks suspiciously like an
> old Ford automobile starter.
The motor is small by EV standards, but too big to be a Ford starter.
I'd guess it is about 5" diameter and 14" long, so a bit bigger than a
golf cart motor.
> The claims for horsepower, 15 continous and 40 intermittent are
> outrageous. At 36 volts, 15 hp requires at least 400 amps and
> 40 hp requires at least 1100. The little motor simply couldn't
> handle such high currents.
To be fair, "continuous" in a vehicle that goes 30 mph with a 10 mile
range is only 20 minutes. I could believe that this size motor could run
that long if it has a cooling blower (although none is shown).
> To make a serious EV would require a motor like the ADC 8-inch
> and at least a 96-volt battery pack.
Yes, for a normal-weight car and normal highway speeds. But I got the
impression that this is more like a neighborhood EV, like a CitiCar.
--
"The two most common elements in the universe
are hydrogen and stupidity." -- Harlan Ellison
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Peter VanDerWal wrote:
> I'm familiar with using induction motors as generators. FWIW, you
> can't usually draw three phases off them at any significant current
> with out collapsing the fields.
Sure you can! The basic requirement is that you need enough capacitance
on each phase so the power factor (capacitors plus load) maintains
around a 0.8 leading power factor. The higher the load current, the more
capacitance you need.
And, of course you need at least one capacitor per phase.
> At any rate, at the low power, low voltage levels that I'm looking
> for (30V @ ~8 amps) the aren't really a viable candidate.
It would work if you found the right motor (something like a 24vac 1/4hp
1-, 2-, or 3-phase induction motor). But what really rules it out is
that you wanted high efficiency. Induction motors (and thus induction
generators) are not the best for efficiency.
--
"The two most common elements in the universe
are hydrogen and stupidity." -- Harlan Ellison
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
> Peter VanDerWal wrote:
>> I'm familiar with using induction motors as generators. FWIW, you
>> can't usually draw three phases off them at any significant current
>> with out collapsing the fields.
>
> Sure you can! The basic requirement is that you need enough capacitance
> on each phase so the power factor (capacitors plus load) maintains
> around a 0.8 leading power factor. The higher the load current, the more
> capacitance you need.
Well, that's why I said 'usuallly'. I understand it's supposed to work in
theory, but every time I've read about someone trying it, they end up
drawing to much current to keep it self excited and it rapidly cycles
down.
However, I admit I have very little exposure to this so perhaps other have
been more successful.
--- End Message ---
--- Begin Message ---
> If Peter's gen is low voltage, and cost is the priority concern,
> I'd use shottky rectifiers and live with remaining losses.
>
> Is there a way to use higher voltage option Peter?
Well I have considered 48V-60V, but for various reasons I'd like to keep
it below 36V.
AMong other issues, I'd like to spin the generator at < 1,000 RPM and I'd
like to keep it as light as possible.
The main reason I'm thinking three phase PM alternators, is because that
seems to be where the small scale wind turbines are heading. Since I have
similar power and voltage requirements, I figured I'd follow where the
folks with all the experience are leading.
FWIW I have been using pancake style DC servomotor, basically a miniature
Etek. I'm just trying to see if I can improve the efficiency some without
spending a fortune.
--- End Message ---
--- Begin Message ---
I have lots of BLDC motors that will easily put out
8 Amps at 30 volts using a 3 phase diode bridge on
the motor phases. I do this in the lab sometimes to
provide a cheap and dirty load for an improvised dyno.
I have a perfect motor for the job, 5" diameter with
a Neodymium Iron Cobalt rotor and a finned aluminum
heatink housing.
It could easily do several times the current your
looking for, I just need to know the RPM range to see
if it is a match.
http://www.qsl.net/w8rnh/dyno/dyno1.jpg
The gold motor on the right is the same diameter
except
longer than the one I have in mind.
This page loads ssslllloooowwww...........
Rod
--- Peter VanDerWal <[EMAIL PROTECTED]> wrote:
> I'm familiar with using induction motors as
> generators. FWIW, you can't
> usually draw three phases off them at any
> significant current with out
> collapsing the fields. Normally folks only use
> these for single phase
> output.
>
> At any rate, at the low power, low voltage levels
> that I'm looking for
> (30V @ ~8 amps) the aren't really a viable
> candidate.
>
> > You could consider an induction motor run as a
> generator for higher
> > voltage systems instead of a synch alternator. All
> you need is a bank of
> > capacitors and to auto excite the machine and 6
> diodes to rectify the
> > output. These machines are cheap but have slightly
> less efficiency than
> > a well designed alternator. You could supply
> batteries of about 120V and
> > up. Lower voltages will need a matching auto
> transformer. Induction mcs
> > have ideal characteristics to battery charge but
> must always have a
> > load. Loose your load and very high voltages are
> produced.
> > David
> >
> > -----Original Message-----
> > From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On
> > Behalf Of jerry dycus
> > Sent: Tuesday, 1 March 2005 12:58 AM
> > To: [email protected]
> > Subject: Re: Question: Max efficiency charging
> with 3 phase alternator
> >
> > Hi Raymond and All,
> > --- Raymond Knight <[EMAIL PROTECTED]>
> wrote:
> >
> > I assume you are talking about auto-truck
> > alternators as 3ph can be a good amount better
> than
> > that.
> > But they until higher voltages and larger
> sizes
> > won't be nearly as eff as a PM or shunt DC
> generators
> > especialy at lower voltages with eff of 85-93% or
> so.
> > Of course YMMV!
> > And I can almost garrantee that engineers
> are
> > not responseable for most problems, ineff of
> > auto-truck alts but accountants, corporate cost
> > cutters instead!
> > I use a surplus 70 amp PM motor at probably
> > 85-88 % eff for my EV hybrid generator to get the
> max
> > from my engine as it's fairly small at 5.5 hp and
> > keeps it lightweight, under 75lbs.
> > An E-tek would be even more eff at 90% for
> him or
> > so, more costly than mine but for me won't go to
> 80-90
> > vdc I'll need for my next EV 72vdc nom batt pack.
> > For anyone wanting to charge batts or make a
> > hybrid a PM or shunts generator is a much better
> > choice and can be used to start the ICE and
> possibly
> > add acceleration power directly to the drive train
> as
> > a motor when needed.
> > I'll just use mine as a series sometimes
> hybrid,
> > range extender as it will be able to be taken off
> when
> > not needed.
> > HTH's
> > jerry dycus
> >
> >> The most efficient commercial available units are
> >> only 74%. They can produce
> >> a ton of amperage, Ecoair is
> >> 240amps/12volts/1650shaft rpm, 310amps max. The
> >> Bosch is only 160amps max, don't know about its
> >> lower rpm, I think around
> >> 100amps. Ecoair is getting ready for production a
> >> 140amp/12volt/1650shaft
> >> rpm alternator as well. They can be factory
> adjusted
> >> to charge at up to
> >> 48volts, so you can get them preset at 30volts.
> They
> >> have temperature
> >> compensation and they use the bucking when the
> >> alternator is not needed. The
> >> Ecoair would probably be a 1300-1500 dollar
> >> adventure. The new model soon to
> >> be released will be half that? The Ecoair gets
> its
> >> efficiency from a coil
> >> wound and permanent magnet rotor assembly, the
> Bosch
> >> claims it is done with
> >> more efficient stator windings. I have never seen
> >> the Bosch up close so I
> >> can give you more specifics about it.
> >> The Denso on the newer Chryslers is using a
> square
> >> wire stator, and we are
> >> seeing very good turn on/bottom end amperages
> from
> >> it. How efficient it is I
> >> don't know. But since it is producing high rates
> at
> >> very low rpm and not
> >> burning up, I would think it is better than the
> >> normal 50%-55% of a claw
> >> pole alternator.
> >> And for the record on the other thread, I have
> >> either built or overseen the
> >> production/repair of over 25,000
> >> starters/alternators/DC motors in just the
> >> last 10years. AERAC was founded in my parents
> >> kitchen 20+ years ago, so I do
> >> know a little bit about them. :) I may not be an
> >> engineer, but I make my
> >> living correcting their mistakes. No offense
> >> intended to the engineering
> >> community with that.
> >>
> >>
> >
> >
> >
> >
> > __________________________________
> > Do you Yahoo!?
> > Yahoo! Mail - Find what you need with new enhanced
> search.
> > http://info.mail.yahoo.com/mail_250
> >
> >
>
>
--- End Message ---
