EV Digest 6066
Topics covered in this issue include:
1) Re: Mechanical control, was: Re: EV controllers? the 4th option...
by "Roland Wiench" <[EMAIL PROTECTED]>
2) Re: Power Battery
by [EMAIL PROTECTED]
3) Re: Mechanical control, was: Re: EV controllers? the 4th option...
by Jack Murray <[EMAIL PROTECTED]>
4) Re: 72V Power Supply - Can I build one?
by "Roland Wiench" <[EMAIL PROTECTED]>
5) Re: Mechanical control, was: Re: EV controllers? the 4th option...
by [EMAIL PROTECTED]
6) "Who Killed the Electric Car" IN FULL on the WEB ! ! !
by Steven Lough <[EMAIL PROTECTED]>
7) No emails
by [EMAIL PROTECTED]
8) Re: inexpensive, homebuilt, Contactor Controller...
by "Peter VanDerWal" <[EMAIL PROTECTED]>
9) Re: Mechanical control, was: Re: EV controllers? the 4th option...
by "Peter VanDerWal" <[EMAIL PROTECTED]>
10) RE: Mechanical control,
was: Re: EV controllers? the 4th option. ..
by "Peter VanDerWal" <[EMAIL PROTECTED]>
11) Re: Floodies/Batt. murder mystery/Thanks to Roger & Roland
by "David Roden" <[EMAIL PROTECTED]>
12) Low Tech EV Drivetrains
by "Bruce" <[EMAIL PROTECTED]>
13) Mechanical control, was: Re: EV controllers? the 4th option...
by Jeff Major <[EMAIL PROTECTED]>
14) Re: Low Tech EV Drivetrains
by "Roland Wiench" <[EMAIL PROTECTED]>
15) Re: Mechanical control, was: Re: EV controllers? the 4th option.
..
by Danny Miller <[EMAIL PROTECTED]>
16) Re: Mechanical control, was: Re: EV controllers? the 4th option...
by "Dave Wilker" <[EMAIL PROTECTED]>
17) Re: Low Tech EV Drivetrains
by "Stefan T. Peters" <[EMAIL PROTECTED]>
18) Re: Mechanical control, was: Re: EV controllers? the 4th option. ..
by "Peter Gabrielsson" <[EMAIL PROTECTED]>
19) AGM battery charging
by Storm Connors <[EMAIL PROTECTED]>
20) How watts per hour for typical car at 60 miles per hour on freeway?
by GWMobile <[EMAIL PROTECTED]>
21) Re: EV controllers? the 4th option...
by "Rich Rudman" <[EMAIL PROTECTED]>
--- Begin Message ---
Yes, the contactor controller is very efficient if you stay at one speed and
never stop or accelerated.
I had one of these units that I got from a Air Force savage yard that you
can bid or buy, that was used for a load bank. It consisted of ten 500 amp
plus contactors and a very large resistor bigger than a car radiator with
multiple taps.
A drum type selector switch would select each contactor, which then would
tap a different resistance value which provides a different voltage that
steps the voltage by 10 ten times.
The problem is, that it becomes a maintenance nightmare to maintain. It
requires you to pull all the contacts every month for cleaning and
reshaping. About once a year, you replace the contacts which may cost up to
$250.00 per kit for silver tungsten type.
At todays cost, these contactors cost over $500.00 each and the resistor
which must be over 100,000 watts or more is in the $1000.00's.
Cheaper to buy a Zilla.
Roland
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Wednesday, October 25, 2006 9:35 PM
Subject: Re: Mechanical control, was: Re: EV controllers? the 4th option...
> >> It'd work, just be exceptionally inefficient if you tried to do it with
> >> a
> >> series motor. Instead of having 80% of the battery available energy
> >> turned into motion, you may be as bad as 30%.
>
> From: "Ted C."
> > What's the problem with that? Millions of people every day drive cars
> > powered by ICE motors every day. We don't hear to many of them
> > complain about 30% efficiency.
>
> An ICE has a range of perhaps 300 miles even with its 30% efficiency.
> If its engine was 100% efficient, its range would be more like 1000 miles
> on a tank of gas.
>
> An EV has a range of more like 30 miles, and that's *with* an efficiency
> of 80% or more. If its efficiency were 30%, its range would be more like
> 10 miles. That's unacceptable.
>
> I think what you're looking for is a contactor controller. This is what
> they
> used 100 years ago for EVs. They are crude and jerky, but almost 100%
> efficienct and very simple. Basically, it is a bunch of switches that wire
> the batteries in various series/parallel combinations to get the desired
> motor speed.
>
>
--- End Message ---
--- Begin Message ---
[EMAIL PROTECTED] writes:
I have used some other brand telecom SLA batteries in smaller vehicles with
good results so far (1 to 2 years of occasional use). They seem to be a lot
less expensive than Optimas and Hawkers and the like, although not rated for
vehicle use. I have no idea if they would stand up to highway vibration or
cycle life. My applications were in the 10 to 20 mph range.>>>>
In the BMW motorcycle community we have been using Panasonic SLAs for years
now as replacement bike batteries (20 and 28 AH ones). They work well in
that application, despite the vibration of the machines. We get 'em from
DigiKey at a decent price. Conventional wisdom is to replace them every three
years
as they do tend to fail suddenly rather than s;owly going bad as most
"slosh" batteries do....
Matt Parkhouse
Colorado Springs, CO
--- End Message ---
--- Begin Message ---
I was at the electronics junk store the other day, and they had a huge
rheostate, about 8" in diameter, i think they wanted $100 for it.
But hey, if you're going to go super low-tech, like the Amish, what's
wrong with a good horse? Or maybe Mr. Flinstone got it right, update it
with some good birkenstock sandals. just joking and jabbing :)
but really, forget mechanical electrical control, and use mechanical
DRIVE, as in a wind-up spring car.
Jack
Roland Wiench wrote:
Yes, the contactor controller is very efficient if you stay at one speed and
never stop or accelerated.
I had one of these units that I got from a Air Force savage yard that you
can bid or buy, that was used for a load bank. It consisted of ten 500 amp
plus contactors and a very large resistor bigger than a car radiator with
multiple taps.
A drum type selector switch would select each contactor, which then would
tap a different resistance value which provides a different voltage that
steps the voltage by 10 ten times.
The problem is, that it becomes a maintenance nightmare to maintain. It
requires you to pull all the contacts every month for cleaning and
reshaping. About once a year, you replace the contacts which may cost up to
$250.00 per kit for silver tungsten type.
At todays cost, these contactors cost over $500.00 each and the resistor
which must be over 100,000 watts or more is in the $1000.00's.
Cheaper to buy a Zilla.
Roland
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Wednesday, October 25, 2006 9:35 PM
Subject: Re: Mechanical control, was: Re: EV controllers? the 4th option...
It'd work, just be exceptionally inefficient if you tried to do it with
a
series motor. Instead of having 80% of the battery available energy
turned into motion, you may be as bad as 30%.
From: "Ted C."
What's the problem with that? Millions of people every day drive cars
powered by ICE motors every day. We don't hear to many of them
complain about 30% efficiency.
An ICE has a range of perhaps 300 miles even with its 30% efficiency.
If its engine was 100% efficient, its range would be more like 1000 miles
on a tank of gas.
An EV has a range of more like 30 miles, and that's *with* an efficiency
of 80% or more. If its efficiency were 30%, its range would be more like
10 miles. That's unacceptable.
I think what you're looking for is a contactor controller. This is what
they
used 100 years ago for EVs. They are crude and jerky, but almost 100%
efficienct and very simple. Basically, it is a bunch of switches that wire
the batteries in various series/parallel combinations to get the desired
motor speed.
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: "martin emde" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, October 26, 2006 12:50 AM
Subject: Re: 72V Power Supply - Can I build one?
> Actually I already connected the motor to a 12v battery to verify that the
> motor works. It's the motor/controller interface that I'm concerned with.
> I have a feeling the controller has a lock-out and will not function if
> the
> voltage is below some threshold, say 66V. Same with the circuit board
> that
> includes the DC-DC converter and other control. I kind of like the "find
> 6
> old batteries at the junkyard" idea.
> Thanks.
> Martin
>
Hello Martin,
What I did, was to run my 165 volt GE 11 inch 32 hp motor for testing, was
connecting to a 12 volt battery, using a simple switch control that
connected the 12 volt battery directly to the motor.
I used one of those small clear plastic tool boxes, to install one of those
500 amp 12 volt battery cut off switches, the one with that large red flag
type handle you can get from a parts store for $12.00.
Also I pick up a 12 volt and amp meter which was install in this box.
Install a 100 amp fuse and input and output alligator clips that goes to a
battery and to the motor.
I first leave the 500 amp switch off, then connect to the leads to the motor
and than to the batteries.
Make sure that the motor is bolted or tie down, and than turn on the switch.
My motor draws about 15 amps starting at 12.8 volts and runs about 2000 rpm
at no load. I use this set up to break in my brushes or to recondition my
commentator at this lower voltage.
If you run the motor for extended periods, watch the volt meter, as you
should not go below 10 volts. Some times when the voltage reaches 10 volts
you may have only seconds to turn the switch off, because I find the voltage
will drop very fast at that point. You could connected a battery charger
with a rating of 30 amps to the battery. It will charge the battery and run
the motor. Do not run the battery charger without the battery connected.
When my EV was in maintenance, I could move my EV inside the shop as needed.
This takes about 50 to 60 amps to move it in first gear.
I have another build in 500 amp switch in my EV with a set of leads, I can
clip directly to the motor in case my controller went out and can still move
the car off the road if needed.
Roland
--- End Message ---
--- Begin Message ---
In a message dated 10/25/2006 8:53:23 PM Mountain Standard Time,
[EMAIL PROTECTED] writes:
Thanks.
Ok so scrap the rheostat .
Would it be more efficient as a pure full on full off switch with some
sort of motor smoothing in the drive tran?
Oh my goodness! My three wheeled trike - an unholy marriage of golf cart
and old BMW bike bits with an 8HP motor wants to shoot out from under me if I
goose the controller too quickly! Couldn't imagine doing that with an
"on-off" arrangement. With a bit of control, all that starting up torque is
real
nice - I beat most cars across the intersection - but PLEASE! No "on-off"!
Matt Parkhouse
Colorado Springs, CO
--- End Message ---
--- Begin Message ---
Language Rating: PG
I bet you any thing that it has to do with that LA Times Reporter's
comments in the movie where he says ( something like )
" If people wanted cars that ran on Pig [EMAIL PROTECTED] GM would build
them"
or something close to that.
Funny... he was pritty NEGATIVE but since that, I have seen him in
interviews on the Tesla Roadster, where he was very Posative and Efusive
even... ( wonder what changed his outlook ??)
--
Steven S. Lough, Pres.
Seattle EV Association
6021 32nd Ave. N.E.
Seattle, WA 98115-7230
Day: 206 850-8535
Eve: 206 524-1351
e-mail: [EMAIL PROTECTED]
web: http://www.seattleeva.org
--- End Message ---
--- Begin Message ---
I have not received any emails since 8 PM last evening (Oct. 25). My email
address is [EMAIL PROTECTED]
--
In Friendship, Ted
//ted.sanders.home.comcast.net
//ffni.home.comcast.net
--- End Message ---
--- Begin Message ---
Here is one I did up a long time ago for electric bikes.
http://www.vanderwal.us/ev/diagrams/controller2.gif
This is more usefuk as a demonstration of the concept than an actual
design. Finding the relays used in this schematic would probably cost
more than using an PWM controller. You could use either SPDT or DPDT
relays and wire the coils in parallel to get the same results. Also, if
you are using a contactor controller on anything heavier than an e-bike,
you probably want a motor-start resistor too.
Note: on this design the batteries are all wired in series when the relays
are off. This is probably different from most designs, but allows you to
use a 48V charger with the relays off, or a 12V charger with some of them
on.
> Hi all,
>
> Does anyone have a schematic on a parallel/series battery arrangement for
> a
> contactor controller?
>
> Deeply interested in this as yes i agree its low cost and definately
> viable
> for a small ev which i am interested in.
>
> Cheers
>
>
> On 26/10/06, jerryd <[EMAIL PROTECTED]> wrote:
>>
>>
>> HI GW and All,
>>
>> ----- Original Message Follows -----
>> From: GWMobile <[EMAIL PROTECTED]>
>> To: [email protected]
>> Cc: [EMAIL PROTECTED]
>> Subject: Re: Mechanical control, was: Re: EV controllers?
>> the 4th option...
>> Date: Wed, 25 Oct 2006 23:38:56 -0700
>>
>> >Tell more about the contact controller.
>> >
>> >Please realize one of my goals is to keep it home built and
>> >simple.
>> >
>> >I want to stay away from things that require huge labs and
>> >factories like semiconductors.
>>
>> I agree with you as I'm about to go to E
>> controllers for the first time, for the last 10 yrs I have
>> used only CC's.
>> They are made up of switches/contactors that
>> series/parallel the battery pack to different voltages, thus
>> vary the motors power output.
>> In low power EV's, you really only need/have 2
>> speeds, off and on except in parking lots, ect where you
>> need to go slow. Any speeds between that usually is just to
>> get to top speed. To vary speeds between these, you just
>> turn them on and off, depending on whether you need to go
>> faster or slower.
>> And since you need to limit the starting amps so
>> you don't break things, you use a starting resistor, easily
>> made from SS, other wire. For under 1500 lb EV's, get a golf
>> cart resistor series card and rewire them in parrallel is
>> about right, you can add, subtract to get the starting power
>> you want.
>> Field weakening, shorting the field some with say
>> a 12gge, 1' solid copper wire and a contactor, increases top
>> end power, speed and/or allows higher gearing.
>> A viable CC would then be 1 or 2 series/parallel
>> battery bank steps, a starting resistor and a field
>> weakening step or 2, giving 3 to 7 steps, is plenty smooth,
>> no different than a transmission shift when correctly sized.
>> And best, they have lots of power/amps naturally so
>> good starting torque for those times you need to start up a
>> hill, especially in EV's without transmissions, which would
>> need at least a 800 amp rating, price, to match it.
>> Citi-cars that replaced their CC's eith EC's were very
>> disappointed in their lack of power. Only when really high
>> amp EC's come around have they become viable in them except
>> in exceptionally flat places.
>> And the fact you can repair it yourself in a few
>> minutes by carrying a spare contactor or 2 and some
>> contacts, makes it a very good way to have an inexpensive,
>> reliable EV.
>> In my Ewoody, I was perfectly happy with just a
>> starting resistor and full power when it was at 45 mph and
>> 36vdc. Resistor for starting, parking lots and on/off full
>> power at speeds above 10-20 mph. At 48 vdc and 60 mph, it
>> had too much power so needed another speed so went to
>> series/parallel the batts and field weakening to give me
>> field weakening speeds on 24 and 48 vdc and 48 vdc, for 3
>> more steps. If you have a lot of slow, stop and go driving,
>> pick the one with more S/P speeds.
>> Even if you have an EC, you should think about
>> putting in a parallel CC in case it fails, to get home. You
>> already have parts of it anyway to run the EC.
>> CC's have served well for 100+ yrs in commercial
>> use and a perfectly viable, some say better ;^D, controller
>> to use.
>>
>> Jerry Dycus
>> >
>> >I believe that while not the most perfect , an electric car
>> >that could literally be made from a home builder including
>> >homebuilt batteries would have a whole new level of appeal
>> >even if it only did a 20 mile round trip.
>> >
>> >Ok maybe you have to buy the motor off ebay but everything
>> >else can perhaps be built or adapted from low tech
>> >components.
>> >
>> >By the way mit recently came out with a cheap solar heat
>> >powered electric generator using a solar concentrator,
>> >power sterring pumps running off solar heated freon and
>> >linked to a good old car generator to charge batteries.
>> >With great efficiencies and very low cost compared to solar
>> >cells why could that sit in an electric pickup truck and
>> >give great self rechargability?
>> >
>> >
>> >That's the kind of ultra low tech I want to aim for.
>> >
>> >
>> >
>> >On Wed, 25 Oct 2006 9:04 pm, Lee Hart wrote:
>> >>>> It'd work, just be exceptionally inefficient if you
>> >>>> tried to do it with a
>> >>>> series motor. Instead of having 80% of the battery
>> >>>> available energy turned into motion, you may be as bad
>> >>as 30%.
>> >> From: "Ted C."
>> >>> What's the problem with that? Millions of people every
>> >>> day drive cars powered by ICE motors every day. We
>> >>> don't hear to many of them complain about 30%
>> >>efficiency.
>> >> An ICE has a range of perhaps 300 miles even with its 30%
>> >> efficiency. If its engine was 100% efficient, its range
>> >> would be more like 1000 miles
>> >> on a tank of gas.
>> >>
>> >> An EV has a range of more like 30 miles, and that's
>> >> *with* an efficiency
>> >> of 80% or more. If its efficiency were 30%, its range
>> >> would be more like
>> >> 10 miles. That's unacceptable.
>> >>
>> >> I think what you're looking for is a contactor
>> >> controller. This is what they
>> >> used 100 years ago for EVs. They are crude and jerky, but
>> >> almost 100% efficienct and very simple. Basically, it is
>> >> a bunch of switches that wire
>> >> the batteries in various series/parallel combinations to
>> >> get the desired
>> >> motor speed.
>> >
>> >www.GlobalBoiling.com for daily updated facts about
>> >hurricanes, globalwarming and the melting poles.
>> >
>> >www.ElectricQuakes.com daily solar and earthquake data.
>> >
>>
>>
>
>
--
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legalistic signature is void.
--- End Message ---
--- Begin Message ---
It's been tried before, and some folks have even made it work. Lots of
problems though.
I don't think you can use square commbars and brushes, because you need
some way to vary the on vs off time. You could either do steps, or
perhaps wedge shaped bars and move the brushes up and down them.
The next problem is that you would be trying to make/break huge currents,
this will cause arcing and quickly wear down the brushes. So you'd need
some external components to reduce the arcing somehow, maybe an RC or RL
network or something.
Of course now it's not simple any more.
Once you start figuring the time and money needed to develop something
like this, a used PWM starts looking REALLY attractive.
You know it's odd, people are always looking for dirt cheap ways of
building EVs, but you almost never hear about someone trying to build a
carburetor out of tin foil and a funnel. <shrug>
> I wasn't going to post this due to the fear I would be laughed off the
> list but what about this idea...
>
> I thought of a uber simple high amp controller that is "out there"
> Might be good for low budget drag racing.
>
> Imagine a long 24 bar commutator that has big heavy bars on it and 2
> adjustable 4 brush set riggings in which the brush width is the same as
> the comm bar width. This is in the controller box. (problem1, where do I
> get this commutator?)
>
> This commutator is spun with a scooter motor (rpm = switching freq)
>
> Power enters one set of brushes and leaves the other.
>
> Pressing on the throttle cable advances the brush rigging allowing
> overlap and the motor inductance integrates it. (Mechanical PWM overlap
> = duty cycle)
>
> The second set of adjustable riggings is moved away from the accelerator
> by a shunt powered solenoid relative to the current being drawn-(current
> limit!) Could even be adjustable since the solenoid operates against a
> spring and we can adjust the spring tension by loosening the jam nut and
> changing the spring preload.
>
> Possible Names:
> Mechanical PWM, Mechanical transistor, Sparky.
>
>
--
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 ---
Odd...cheap and Sterling don't normally go together. Especially when you
are talking freon and so forth. Reliability is another issue with
Sterling heat engines.
I used to work next to a solar collector sterling generator that was rated
for 10-15kw. It was down waiting for parts more often than it was up and
running. And this was for a high quality piece of equipment that cost
well up in the 6 figure range.
Do you have a link to any information about this on the web?
> By the way mit recently came out with a cheap solar heat powered
> electric generator using a solar concentrator, power sterring pumps
> running off solar heated freon and linked to a good old car generator to
> charge batteries.
> With great efficiencies and very low cost compared to solar cells why
> could that sit in an electric pickup truck and give great self
> rechargability?
>
>
> That's the kind of ultra low tech I want to aim for.
>
>
>
> On Wed, 25 Oct 2006 9:04 pm, Lee Hart wrote:
>>>> It'd work, just be exceptionally inefficient if you tried to do it
>>>> with a
>>>> series motor. Instead of having 80% of the battery available energy
>>>> turned into motion, you may be as bad as 30%.
>>
>> From: "Ted C."
>>> What's the problem with that? Millions of people every day drive cars
>>> powered by ICE motors every day. We don't hear to many of them
>>> complain about 30% efficiency.
>>
>> An ICE has a range of perhaps 300 miles even with its 30% efficiency.
>> If its engine was 100% efficient, its range would be more like 1000
>> miles
>> on a tank of gas.
>>
>> An EV has a range of more like 30 miles, and that's *with* an
>> efficiency
>> of 80% or more. If its efficiency were 30%, its range would be more
>> like
>> 10 miles. That's unacceptable.
>>
>> I think what you're looking for is a contactor controller. This is what
>> they
>> used 100 years ago for EVs. They are crude and jerky, but almost 100%
>> efficienct and very simple. Basically, it is a bunch of switches that
>> wire
>> the batteries in various series/parallel combinations to get the
>> desired
>> motor speed.
>
> www.GlobalBoiling.com for daily updated facts about hurricanes,
> globalwarming and the melting poles.
>
> www.ElectricQuakes.com daily solar and earthquake data.
>
>
--
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 ---
On 16 Oct 2006 at 14:55, Chuck Hursch wrote:
> If I'm spending about 10cents/mile for floodeds, give or take a
> few pennies, AGMs are going to be about three times that much.
Golf car batteries are the indisputable cost leaders. I once worked this
out, and for my car AGMs would have cost >SEVEN TIMES< as much per mile as
golf car batteries. (Except for one small problem; I couldn't fit 144
volts' worth of golf car batteries to a Geo Metro without collapsing it. ;-)
USBMC 2200 - 2 cents per mile
Saft STM5-100 - 4-6 cents per mile
Trojan 27TMH - 8 cents per mile
Optima G31 - 14 cents per mile
As they say, your mileage may vary; do the math for your own vehicle before
assuming anything.
David Roden - Akron, Ohio, USA
EV List Assistant Administrator
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--- Begin Message ---
GWMobile wrote:
> I believe that while not the most perfect , an electric car that could
> literally be made from a home builder...
> would have a whole new level of appeal
This sounds like an interesting topic. What about making the car drivetrain
easier to home fabricate?
The usual approach is to machine an adapter plate and a coupling to connect
the motor to the donor car's clutch or transmission. Precision counts here
as you certainly want the two to be in good alignment and the connection to
be reliable. But this is not something that can be easily home fabricated.
Are there other ways to accomplish transmitting the power from the electric
motor into making the car move forward?
1) Belt or chain drive. Easier to align. But where do you put the driven
sprocket or pulley?
A) On the trans/clutch? That input shaft is probably not designed for
the side loads that a chain drive would produce.
B) On the differential?
C) On the wheel drive shaft(s)?
D) On the wheel(s)?
2) Gear drive. The simplest EV conversion would be just to drive the car by
holding the key in the start position with the car in gear. The starter
motor would turn the flywheel by its existing gear drive. It would probably
overheat the starter motor after a few hundred feet of driving. So you
replace the starter motor with a motor more suited to continuous duty. But
that motor pinion and flywheel ring gear really should be in an oil filled
gearcase...
3) Friction drive directly to the wheel like on an inexpensive bicycle
assist motor. This method has the advantage over others in that the
existing drivetrain does not need to be modified or even removed for that
matter. Have your electric motor drive a small pneumatic tire by chain
drive and then press that tire directly against the top of one of the rear
wheels with enough force to keep the two from slipping. How much friction
would be added by this arrangement? In a well designed system, perhaps less
than one might think. On a conventional drive car, there are 4 tire
deflection patches, one for each tire contacting the road. On this setup,
there would be 2 additional tire deflection patches.
4) Air drive. Power a propeller or a centrifugal blower by the electric
motor and blow the air out the back to make the car go forward. Probably
not street legal...
5) Direct drive. Suitable hub motors are not usually found cheap. Making
them might not be any easier. Direct drive to the differential would be
easier, but then you are back to precision shaft alignment. How about a
front engine/rear drive car with direct drive to the driveshaft through the
U-joints? Most cars of this type are not recent or light weight and the
motor would have to turn at pretty low RPMs since you don't have the gear
reduction of the transmission.
Have I missed any other drive methods?
Which of these seems the most practical?
What affordable EVs have others seen or heard of that use a non conventional
drive system?
--- End Message ---
--- Begin Message ---
Jeff,
This basic idea has been done. Probably in more than one version. I
actually was involved in the prototype build and test of one type called the
Middlebrook Rotary Transformer. Named after the inventor, Dr. Middlebrook. I
think I remember the spelling correctly. It was some 25 years ago. He did
have a patent on it. You may be able to search it out. The device was
basically a shunt motor with an extra long comm and two additional sets of
counter-rotating brushes which would pick off reduced voltages from
intermediate angular positions on the comm. It actually worked quite well and
even had current multiplication. We prototyped it in a 24 volt 200 amp
version. Never went commerical due to complexity and expense of comm and all
those brushes and holders and springs and connectors and so on. Another nice
thing about electromechanical rotary control devices such as this is that you
call pull mechanical power off the shaft for power steering, A/C, etc.
Jeff Major
Jeff Shanab <[EMAIL PROTECTED]> wrote:
I wasn't going to post this due to the fear I would be laughed off the
list but what about this idea...
I thought of a uber simple high amp controller that is "out there"
Might be good for low budget drag racing.
Imagine a long 24 bar commutator that has big heavy bars on it and 2
adjustable 4 brush set riggings in which the brush width is the same as
the comm bar width. This is in the controller box. (problem1, where do I
get this commutator?)
This commutator is spun with a scooter motor (rpm = switching freq)
Power enters one set of brushes and leaves the other.
Pressing on the throttle cable advances the brush rigging allowing
overlap and the motor inductance integrates it. (Mechanical PWM overlap
= duty cycle)
The second set of adjustable riggings is moved away from the accelerator
by a shunt powered solenoid relative to the current being drawn-(current
limit!) Could even be adjustable since the solenoid operates against a
spring and we can adjust the spring tension by loosening the jam nut and
changing the spring preload.
Possible Names:
Mechanical PWM, Mechanical transistor, Sparky.
---------------------------------
Get your own web address for just $1.99/1st yr. We'll help. Yahoo! Small
Business.
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I talk to NetGain a while back about why don't you make your motors in a
true traction motor, like my GE traction motor. You just pull the engine
out and it goes directly in place of the engine and connects directly to the
existing transmission or drive line with no adapters and mounts to the
existing engine mounts.
The tech said he recommended this to NetGain, because they were getting a
lot of request for this. Well, Now you can get a Warp 11 this way and they
will have Warp 9's with this configuration.
The Warp 11 motor that I will be getting will be a direct replacement for
the engine, drops right in.
Also if you want to wait about 20 to 30 years, you may get a magnetic motor
that has auto changing poles that requires no main battery pack. The
Liverpool Labs in England are now running small proto types on this design.
Roland
----- Original Message -----
From: "Bruce" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, October 26, 2006 11:31 AM
Subject: Low Tech EV Drivetrains
> GWMobile wrote:
> > I believe that while not the most perfect , an electric car that could
> > literally be made from a home builder...
> > would have a whole new level of appeal
>
> This sounds like an interesting topic. What about making the car
> drivetrain
> easier to home fabricate?
>
> The usual approach is to machine an adapter plate and a coupling to
> connect
> the motor to the donor car's clutch or transmission. Precision counts
> here
> as you certainly want the two to be in good alignment and the connection
> to
> be reliable. But this is not something that can be easily home
> fabricated.
>
> Are there other ways to accomplish transmitting the power from the
> electric
> motor into making the car move forward?
>
> 1) Belt or chain drive. Easier to align. But where do you put the driven
> sprocket or pulley?
> A) On the trans/clutch? That input shaft is probably not designed for
> the side loads that a chain drive would produce.
> B) On the differential?
> C) On the wheel drive shaft(s)?
> D) On the wheel(s)?
>
> 2) Gear drive. The simplest EV conversion would be just to drive the car
> by
> holding the key in the start position with the car in gear. The starter
> motor would turn the flywheel by its existing gear drive. It would
> probably
> overheat the starter motor after a few hundred feet of driving. So you
> replace the starter motor with a motor more suited to continuous duty.
> But
> that motor pinion and flywheel ring gear really should be in an oil filled
> gearcase...
>
> 3) Friction drive directly to the wheel like on an inexpensive bicycle
> assist motor. This method has the advantage over others in that the
> existing drivetrain does not need to be modified or even removed for that
> matter. Have your electric motor drive a small pneumatic tire by chain
> drive and then press that tire directly against the top of one of the rear
> wheels with enough force to keep the two from slipping. How much friction
> would be added by this arrangement? In a well designed system, perhaps
> less
> than one might think. On a conventional drive car, there are 4 tire
> deflection patches, one for each tire contacting the road. On this setup,
> there would be 2 additional tire deflection patches.
>
> 4) Air drive. Power a propeller or a centrifugal blower by the electric
> motor and blow the air out the back to make the car go forward. Probably
> not street legal...
>
> 5) Direct drive. Suitable hub motors are not usually found cheap. Making
> them might not be any easier. Direct drive to the differential would be
> easier, but then you are back to precision shaft alignment. How about a
> front engine/rear drive car with direct drive to the driveshaft through
> the
> U-joints? Most cars of this type are not recent or light weight and the
> motor would have to turn at pretty low RPMs since you don't have the gear
> reduction of the transmission.
>
> Have I missed any other drive methods?
>
> Which of these seems the most practical?
>
> What affordable EVs have others seen or heard of that use a non
> conventional
> drive system?
>
>
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Doesn't seem like a Stirling engine. They boil freon in the collector,
drive a rotary vane, then condense it somewhere and send liquid back to
the collector for boiling. The cycle seems identical to the steam cycle
used in just about any power plant, it's just using freon for a
radically different boiling point.
Danny
Peter VanDerWal wrote:
Odd...cheap and Sterling don't normally go together. Especially when you
are talking freon and so forth. Reliability is another issue with
Sterling heat engines.
I used to work next to a solar collector sterling generator that was rated
for 10-15kw. It was down waiting for parts more often than it was up and
running. And this was for a high quality piece of equipment that cost
well up in the 6 figure range.
Do you have a link to any information about this on the web?
By the way mit recently came out with a cheap solar heat powered
electric generator using a solar concentrator, power sterring pumps
running off solar heated freon and linked to a good old car generator to
charge batteries.
With great efficiencies and very low cost compared to solar cells why
could that sit in an electric pickup truck and give great self
rechargability?
That's the kind of ultra low tech I want to aim for.
On Wed, 25 Oct 2006 9:04 pm, Lee Hart wrote:
It'd work, just be exceptionally inefficient if you tried to do it
with a
series motor. Instead of having 80% of the battery available energy
turned into motion, you may be as bad as 30%.
From: "Ted C."
What's the problem with that? Millions of people every day drive cars
powered by ICE motors every day. We don't hear to many of them
complain about 30% efficiency.
An ICE has a range of perhaps 300 miles even with its 30% efficiency.
If its engine was 100% efficient, its range would be more like 1000
miles
on a tank of gas.
An EV has a range of more like 30 miles, and that's *with* an
efficiency
of 80% or more. If its efficiency were 30%, its range would be more
like
10 miles. That's unacceptable.
I think what you're looking for is a contactor controller. This is what
they
used 100 years ago for EVs. They are crude and jerky, but almost 100%
efficienct and very simple. Basically, it is a bunch of switches that
wire
the batteries in various series/parallel combinations to get the
desired
motor speed.
www.GlobalBoiling.com for daily updated facts about hurricanes,
globalwarming and the melting poles.
www.ElectricQuakes.com daily solar and earthquake data.
--- End Message ---
--- Begin Message ---
Ah, I'm sorry, I don't think i was very clear here. I was thinking more
along the lines of a transistorized chopper, using base bias voltage to
control the Vce junction.
David C. Wilker Jr.
USAF (RET)
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, October 26, 2006 5:04 AM
Subject: Re: Mechanical control, was: Re: EV controllers? the 4th option...
David C. Wilker wrote:
Instead of dissipative current control, can you use switching/chopper
type
control?
From: James Massey
It would be possible to make a motorised chopper, but you would still need
to have freewheel diode/diodes. You would need to be a careful driver,
since current limiting would be difficult to implement on a mechanical
sustem (but not impossible) so would be in the hands (foot) of the driver.
If you are serious about this, research the kind of controls built after
the
contactor controllers of the 1900's, but before the vacuum tube
controllers
of the 1940's. The state of the art back then was the synchronous switch.
The key concept was that an LC resonant circuit was used to cause the
switch voltage or current natually fall to zero at the instant it needed
to be
opened or closed. Arcing was thus minimized, so the switch could last for
billions of cycles. The "vibrator" found in 1940's car radios is an
example
of this technology.
A PWM motor control had a mechanically resonant switch, such as a flat
spring with a contact on it. A pulse to a coil would flex the spring so
the
contact closed, and then opened automatically a fixed time later (fixed
on-time). The motor inductance was resonated with a big capacitor at the
same frequency as the mechanical switch. Each time the switch closed,
the current ramped up from 0 to max, and then back down to almost zero
at the instant the switch opened. The controller controlled the duty cycle
by how often it triggered one of these fixe-on-time cycles.
This is exactly the same principle used in the SCR controllers, where the
SCR replaced the mechanical switch.
--- End Message ---
--- Begin Message ---
Roland Wiench wrote:
I talk to NetGain a while back about why don't you make your motors in a
true traction motor, like my GE traction motor. You just pull the engine
out and it goes directly in place of the engine and connects directly to the
existing transmission or drive line with no adapters and mounts to the
existing engine mounts.
The tech said he recommended this to NetGain, because they were getting a
lot of request for this. Well, Now you can get a Warp 11 this way and they
will have Warp 9's with this configuration.
What ICE engine is this setup intended to replace? Which
transmission/driveline does it interface with?
--- End Message ---
--- Begin Message ---
On 10/26/06, Peter VanDerWal <[EMAIL PROTECTED]> wrote:
Odd...cheap and Sterling don't normally go together. Especially when you
are talking freon and so forth. Reliability is another issue with
Sterling heat engines.
Here's a link to the article in the MIT technology review.
http://www.technologyreview.com/read_article.aspx?id=17169&ch=energy
Sterling was of course never mentioned and neither was efficiency. The
key to solar power adoption is cost which is neatly addressed by using
old car parts.
It's an interesting article, it reminds me of my father in laws pool
heater. He laid out grids of PVC pipes across the roof of his home in
California and pumped pool water through it. No reflectors were
needed, he just painted the pipes black. The system kept his home
cooler and his pool heated, he even had to scale it back some after
steaming hot water came out of it on the first really hot summer day.
-Peter
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Could someone tell me how to charge 144 volts of AGMs. I have a manual
charger. I can adjust the voltage and can measure the amps.
The batteries are 33Ah (20 hr rate) Dynasty UPS12-140FRs. I've buddied pairs,
so I have 24 of them installed. I realize I can't expect much range and they
are a long way from new, but after sitting for a year they were all at
12.2-12.3v. Seems like they should prove the concept.
I learned from Mr. Roden to charged them until the voltage stops increasing
from hour to hour.Other than that, the archives are pretty confusing. What I'd
really like are some specifics like charge at x amps until ... then set voltage
at y until amps drops below z- or something like that.
I know that the best answer is buy a proper charger. I expect these batteries
won't last forever and they will probably be replaced with flooded 8v. Buying
another charger doesn't seem a good option under the circumstances. But I don't
want to kill these either.
Thanks,
storm
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How watts per hour for typical car at 60 miles per hour on freeway?
Obviously many variables like cd etc but just want a round number.
www.GlobalBoiling.com for daily updated facts about hurricanes,
globalwarming and the melting poles.
www.ElectricQuakes.com daily solar and earthquake data.
--- End Message ---
--- Begin Message ---
Reply Line By line.
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Wednesday, October 25, 2006 6:44 PM
Subject: Re: EV controllers? the 4th option...
> From: Rich Rudman
> > This is exactly what I am proposing... High voltage Curtis Killer, with
> > some goodies, not many... 96V to perhaps 192V... 500 amp... is going
> > to cover most anyone who would have bought this controller instead
> > of a Curtis... I am proposing an IGBT module based machine.
>
> IGBTs are generally good for higher voltages and lower currents than
> this. Your controller will have on the order of a 3v drop; that's 1500
watts
> at 500 amps. Dissipating 1500 watts takes some pretty impressive (and
> expensive) heatsinks.
First take 2.1 volts of drop and maybe even 1.8 if the current spec is still
real.
1500 watt is Well doable... good fans needed.
>
> Under 200v, I'd prefer MOSFETs. Use them for both the transistors and
> freewheel diodes (synchronous rectification). This will get the drop under
1v, which mean 1/3rd the heat to get rid of.
Sync Rect is a nice idea.. But comes at a cost that's well a pain. The
diodes in a IGBT module are not the best, But.. good enough.
>
> Modules are really nice because they get rid of dozens of tiny little
devices that must be meticulously wired in parallel. A controller like this
would need a dual MOSFET "half bridge" module.
>
Yup, I pay for somebody else to asseble and balence the discretes.. That's
the whole reason behind modules in the first place.
> >The voltage limits I think are a waste of time.
>
> I disagree. The low limit prevents you from ruining your batteries by
running them dead. The high limit keeps you from destroying the controller
from excessive voltage (typically caused by chargers, or by too much battery
inductance or resistance).
Low volt limits keep you from Killing your pack.
High volt limits on the motor side keep you from killing the brushes and
motor.
High v shut down limits or contactor drops may keep you from vaporizing the
controller. But.. having 600 volt parts, it's going to be rare that you will
exceede these limits.
At over 600 V ... hey yer so far off the data points that a fail will
happen.
>
> > The point is a easy to buld easy to service, simple power stage simple
> > analog controller that just gets the job done.
>
> I agree. There is little point to micros and software in a basic
controller.
> Add a micro-controlled "hairball" if you want bells and whistles, like
cruise
> control, regen, series/parallel contactor switching, etc.
>
Add the Bling to the controller when you have a demand and cash flow to make
it so.
> > precharge/contactor control
> > basic fault detection (open/short throttle, high pedal lockout)
>
> Yes; it's so simple that it would be foolish to leave it out.
>
> > rev limiter (and a tach drive output sure would be nice)
>
The feature list of the Raptor, 10 years later is still a valid one. Been
there, got the Scars.
> For a simple "black box" controller, such functions should be simple
> enough to add that it doesn't need to be designed and integrated into
> the controller. For instance, the controller might just have an "inhibit"
> input that shuts it down if it exceeds X volts. The user could work out
> circuits to apply a voltage proportional to RPM, or temperature, or
> whatever.
>
> > packaged to survive the automotive underhood environment.
>
> Definitely! Too many controllers are being built in places that don't
> have weather. They are packaged like indoor office equipment.
>
> > No I am not making a submersible product.
>
> I would! :-) Use a NEMA enclosure with a heatsink on the outside.
>
UGly!!! That won't happen.
I have some ideas.. But.. I wouldn't put the controller or any power devices
down in the salt spray and road Grime.
A OEM contract might change my angle on this....
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