EV Digest 5343
Topics covered in this issue include:
1) Re: [solectria_ev] A Force broken in San Francisco Back on the Road
by Danny Ames <[EMAIL PROTECTED]>
2) Re: Orb Carnage....
by Lee Hart <[EMAIL PROTECTED]>
3) RE: [solectria_ev] A Force broken in San Francisco Back on the Road
by "Noel P. Luneau" <[EMAIL PROTECTED]>
4) Re: Crazy DC regen idea, thoughts, comments
by Lee Hart <[EMAIL PROTECTED]>
5) Re: Crazy DC regen idea, thoughts, comments
by Jeff Shanab <[EMAIL PROTECTED]>
6) Thermal measurements
by Mike Phillips <[EMAIL PROTECTED]>
7) Re: Prius plug in over in England
by Lee Hart <[EMAIL PROTECTED]>
8) Re: Prius plug in over in England
by "Mike Phillips" <[EMAIL PROTECTED]>
9) Re: AC vs DC; Newbie Question
by John Wayland <[EMAIL PROTECTED]>
10) Re: adventures in electronics
by "John Luck Home" <[EMAIL PROTECTED]>
11) Re: Exide 34XCD fit?
by "Paul G." <[EMAIL PROTECTED]>
12) Re: Porsche 911 Was: How many amps driving my EV?
by Robert Baertsch <[EMAIL PROTECTED]>
13) Re: Orb Carnage....
by "Rich Rudman" <[EMAIL PROTECTED]>
14) Re: Thermal measurements
by "Rich Rudman" <[EMAIL PROTECTED]>
15) Re: Crazy DC regen idea
by Doug Weathers <[EMAIL PROTECTED]>
16) Re: Thermal measurements
by "Roland Wiench" <[EMAIL PROTECTED]>
17) Re: [solectria_ev] A Force broken in San Francisco Back on the Road
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
18) Re: the $5000 car - could use some expert help
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
19) Re: Crazy DC regen idea, thoughts, comments
by Jeff Shanab <[EMAIL PROTECTED]>
20) RE: [solectria_ev] A Force broken in San Francisco Back on the Road
by "Will Beckett \(becketts\)" <[EMAIL PROTECTED]>
--- Begin Message ---
Mike Phillips wrote:
Nice Job!
Does this happen much to Force motors?
If the bearings in your motor were toasted, what about the input shaft
bearing to the transmission? It spins the same speed as the motor and
was designed for half the rpm that the electric motor was running at.
Mike
I gather that its dependent on the amount of driving on steep hills and
the design of the Force.
The motor acts as a break when in regen and that places a large strain
on the bearings in the opposite direction.
The car is constantly stressing the motor bearings because the gear that
engages the rotor tugs on it when in breaking/regen then tugs the
opposite way on acceleration. I was not aware of this design arrangement
when I got my Force last year. But personally feel the car is better
suited for flat lander use.
I can not say if this happens much to Force motors since I 'am only
finding out about this now for the first time.
The bearing life will be severely diminished if one heavily loads it in
this fashion and think Solectria could have done a better job in this
area of the car if cost was not a factor.
Danny
--- End Message ---
--- Begin Message ---
Seppo wrote:
> What would happen if you simply connected a (very sturdy) diode in
> parallel with each battery? If the battery cannot keep in pace with
> the others and starts to go negative, the diode would start
> conducting the load current past the battery when the battery voltage
> is down to -0.7 V.
You can do this. But by the time a +12v battery drops to -1v (so the
diode conducts), that battery is in VERY bad shape!
However, the parallel diode trick has been used in packs of nicad cells.
A nicad cell taken down to -0.5v is *very* dead, but will survive.
But rather than a lot of big diodes (and their associated big
heatsinks), all to achieve a marginal solution, I think it would be
better to include a relay or contactor that switches the dead
battery/cell out of the series string. This requires a SPDT contact; one
to open the battery, and one to short around it. Probably also a diode
to carry the load current during the split second it takes the relay to
switch states.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Hi Danny,
Congrats on being back on the road. Where did you source the
replacement parts?
Thanks,
Noel L
________________________________
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
On Behalf Of Danny Ames
Sent: Saturday, April 08, 2006 8:46 PM
To: [EMAIL PROTECTED]; EV SEND MSG; SFEAA
Subject: Re: [solectria_ev] A Force broken in San Francisco Back on the
Road
Wanted to share my good news.
Just completed the final repair work today and its working great.
With all the rain storms here in soggy California and my limited time
available to work on the car it has been a challenge.
Fortunately I was able to get a new sensor and get the motor in and out
ok between dry times.
Motor bearings were replaced due to excessive axial play.
The sensor board was also bad due to it getting banged.
Runs like a top.
Danny
Danny Ames wrote:
>After several months of carefree driving we have now been down for
>several weeks.
>I have bee reluctant to post my story and a bit depressed and needed to
>do some checking.
>In my several calls to various people feel ready to run this by those
on
>the list.
>What happened is the car starting bucking on de-acceleration and got
>progressively worse till finally it stopped moving in downtown rush
hour.
>I examined the speed sensor disk and could see the lines scratched off
>where the detector pair on the speed sensor is placed.
>I re-inked the disk lines with a sharpie and tried to makes several
>adjustments but could not get it going at all and had the car towed
home.
>Jacked up the front end so the wheels could turn freely.
>Completely backed off the sensor and the motor would turn smoothly and
>slowly.
>In testing I adjusted the sensor closer in small increments to the disk
>and then the motor started to respond in a very erratic and rough
>stepping motions. The axial motion of the motor armature starting
>jumping about at what appears to be .125 inch so the disk is moving to
>and fro in this sputtering effect to the sensor and is very choppy
>The motor bearings seem noise free but the armatures axial movement
>maybe to great and the trouble possibly.
>When the motor is at rest the disk is about flush to the motor face.
>I can see the motor mounts with 3 bolts, so does one remove these and
>simply slide the motor out.
>Also how does the motor shaft engage to the transmission?
>Hopefully I am on the right track to fixing this.
>Danny
>
>
>
>
>
>
>
>
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
>
________________________________
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--- End Message ---
--- Begin Message ---
Robert Chew wrote:
> Would it be possible to PWM the current to the motor armature via the
> motor controller to the A1 and A2 terminals of the ADC 6.7 inch and
> then grab the regen power from the field windings. Would that be in
> AC current from the field windings?
Not with the normal series motors used in EVs. Two reasons:
1. If you look at the armature and field windings as a transformer,
the armature has many more turns. Thus, it acts as a step-down
transformer. 100vac into the armature might only produce 10vac in
the field. You'd still need something to step this AC up high
enough to charge the batteries.
2. The armature is laminated, and so can handle higher frequencies
fairly efficiently (audio frequencies). But the field (in particular,
the outside iron case) is solid steel. It has high AC losses at
anything over a few 10s of Hz. So most of the regen power you'd get
would be burned up in the field as heat.
Now, you *can* use this trick with motors having laminated iron in their
field structure. Universal motors can do this; they are a series motor
that runs on straight AC, without rectifying it first; you find them in
vacuum cleaners and electric drills.
And, of course an AC motor always has laminated field iron.
If you want to try something different, put an AC induction motor's
stator around a DC motor's armature. You now have a repulsion motor.
They used to be very common, as it is an AC motor that has very high
starting torque yet low starting current. It can also run *above*
synchronous speed. Their main drawback was higher cost, because you have
a wound rotor and commutator.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
I don't thing that will work because the way the individual windings of
the armature change polarity.
Each armature winding is connected to the next in 1 series loop with a
comm bar brought out at each connection.
looking at the top and bottom brushes as + and the right and left
brushes as negative, we see all the coils to the right of the top brush
flowing to the brush on the right have current flowing clockwise thru
the armature windings generating little North poles (I think, may be
left hand rule, whatever) Ok and all the armature coils to the left of
the top brush have current flowwing to the left brush counter-clockwise
thru the armature coils makeing south poles.
Now here is the slick part: as a coil emerges from under the field it's
comm bar goses under the brush. The brush is fat and the coil is
momentarily shorted by the brush, which squelches what would be a nasty
induced arc (think coil in car) This is furthor reduced by the fact
that it has come out from under the field's magnetic field and so the
voltage induced is zero. Now the voltage goes into that coil and towards
the right brush so curent flows clockwise and it pulls toward the next
field.
Now it is easy to see what causes flashover. That armature coil coming
out tends to drag the field's magnetic field along with it. the higer
the rpm's the more it distorts the field. Eventually the voltage is
significantly more than zero and the arc forms. Sadly dragged along by
the rotating commutator and, well, the rest is history.
Rotating this brush timing is one way to compensate. so are Interpoles.
and "compensator" windings
The only reason the slip ring idea can work is that the brushes are out
of the circuit at that time, We can't for example put the car in
neutral, set the controller to 1800 rpm and get some nice 60 cycle 3
phase, because part of the 120 degree coil will be flowwing one way and
part the other. Indeed, we must also disconnect the 2 points of contact
of the slip ring or it will short the DC commutator function. Perhaps a
diode connected slip-ring? I have to get a piece of paper and draw it out.
--- End Message ---
--- Begin Message ---
Has anyone measured their battery temperatures? Just curious what you
used and what numbers you got in various conditions.
I'm secretly hoping for proven schematic with part numbers cause I'm
buried right now.
But even meat thermometers qualify to answer the question.
Mike
Here's to the crazy ones.
The misfits.
The rebels.
The troublemakers.
The round pegs in the square holes.
The ones who see things differently
The ones that change the world!!
www.RotorDesign.com
--- End Message ---
--- Begin Message ---
Mike Phillips wrote:
> Great article. It repeats itself. Some Paragraphs also repeat
> themselves.
Good things bear re-repeating. :-)
As owner of a Prius, the main problem I've seen so far with all the
plug-in hybrids is that they are cost-is-no-object approaches. It looks
to me like Toyota picked a good compromise between battery cost and
pure-electric range.
To increase pure-electric range, I wish they would look at *cheaper*
battery options rather than more expensive ones. On a cost per KWH
basis, plain old lead-acids would be better. Most people drive with only
one person in the car, yet it has GVWR enough for four. So, add a few
hundred pounds of lead acids to get the extra range.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Yes they do ;)
The guys at CalCars.org did just that. 20ah AGM's. It worked pretty
well. Now They are moving to Lithium I believe.
At the Maker Faire this month they are going to convert a Prius to a
Plug in Prius right in front of everyone, then the owner drives it
back to Washington/Oregon.
Mike
--- In [EMAIL PROTECTED], Lee Hart <[EMAIL PROTECTED]> wrote:
>
> Mike Phillips wrote:
> > Great article. It repeats itself. Some Paragraphs also repeat
> > themselves.
>
> Good things bear re-repeating. :-)
>
> As owner of a Prius, the main problem I've seen so far with all the
> plug-in hybrids is that they are cost-is-no-object approaches. It looks
> to me like Toyota picked a good compromise between battery cost and
> pure-electric range.
>
> To increase pure-electric range, I wish they would look at *cheaper*
> battery options rather than more expensive ones. On a cost per KWH
> basis, plain old lead-acids would be better. Most people drive with only
> one person in the car, yet it has GVWR enough for four. So, add a few
> hundred pounds of lead acids to get the extra range.
> --
> Ring the bells that still can ring
> Forget the perfect offering
> There is a crack in everything
> That's how the light gets in -- Leonard Cohen
> --
> Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
>
--- End Message ---
--- Begin Message ---
Hello to All,
Mike Phillips wrote:
The biggest thing that bugs me about most DC systems is the huge
amount of current the battery's have to supply just to leave a stop
light. That's hard on everything involved.
Huge amount of current just to leave a stop light? Where do you get that
from? The average 144V-192V DC systems do not have to use 'huge
currents' just to leave a stop light. My 156V car takes just 50-100 amps
to leave a stop light at speeds matching traffic flow. In order to match
the not-too-exciting 100 kw AC system's 'maximum' leave the stop light
capability, it still only takes about 300 hundred amps through a
transmission, something most everyone uses with these DC systems. The
huge currents (really not all that huge) only come into play when one
wishes to demonstrate the 144V-192V DC system's 6-7 second 0-60
acceleration capabilities, such as when wanting to dust off one of those
lower powered 100 kw AC systems :-) Using quality AGM batteries (wimpy
gel cells need not apply) like Optimas, Hawkers, or Orbitals, the high
currents are not a problem at all, in fact, these tough batteries seem
to thrive under such treatment...witness my Optimas that finally died
after 6.5 years of nearly constant high current acceleration blasts!
Witness the Exide Orbitals that never, ever failed under repeated 1/4
mile drag strip runs. Witness the Hawkers in White Zombie that never,
ever failed throughout the 2005 racing season.
With most AC systems you
need higher voltage to get the watts up, but the battery pull 500 amps
max on the high powered systems I am familiar with. Many limit to 200
amps. That makes battery and interconnect choices easier.
You can get the exact same results in a high voltage DC system, so I
find this comparison you've made interesting, because it's an apples to
oranges thing. High voltage AC to low voltage DC? If you want the low
current battery thing you 'seem' to be saying is the AC's advantage,
then simply run a high voltage DC system....you know, apples to apples.
In White Zombie, at 348V, it only takes about 50 amps from the battery
pack to accelerate as a normal car does in average street driving, and
it takes a whopping 20-25 amps to cruise at 55-60 mph. Driving as if I
were in a 96V Rabbit or a Solectria Geo Metro, the car uses about 40
amps from the batteries to accelerate up to speed. The difference of
course, is that my high power DC setup gives me the option of pulling
1000 amps from the high voltage pack (if I so deem it necessary and have
it programmed the max battery amps this way) for extreme acceleration,
something the 100 kw AC system you are comparing to, cannot remotely
achieve.
The beauty of the 144V-192V DC systems is that you can afford these,
they give superior acceleration when compared to the 100 kw AC systems
that are double the cost, and using quality AGM style batteries, in
particular the three brands I've mentioned that have a proven track
record (pun intended), there really are no cabling or connector issues.
The only AC failure I've ever known was when the 12v accessory battery
got hooked up backwards ;)
The AC powered S-10 (Hughes Dolphin 50 kw) I had in my possession years
ago failed, big time. The repair would have been so expensive that the
truck was salvaged by the owners instead of being repaired. A DC truck
would have been back on the road at minimal cost. The AC systems Victor
(Metric Mind) sells have a very good reliability record.
It seems odd that you would favor an AC system at twice the cost,
twice...because it 'bugs you' to pull high amps from a battery pack,
when a DC system at the same voltage does the same thing while also
giving you far more available power at far less dollars.
See Ya......John Wayland
--- End Message ---
--- Begin Message ---
That will be the reverse protection diode normally connected across the
black and the red output socket.
Use a multimeter and check for short circuit across the red and black
terminals. If it is, open up the PSU and trace the wiring back and sometimes
on a small daughter PCB you will find a diode. I guess it will be short.
John
----- Original Message -----
From: "Fortunat Mueller" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Saturday, April 08, 2006 6:22 PM
Subject: adventures in electronics
Hi all,
Some of you may remember when I reported that on my
very first test drive with Nicds, i reversed one
'module' of batteries (20 BB600 cells per 'module')
because i stupidly hadn't charged them the same as the
rest.
Anyway, when i got back to my garage and realized what
I had done, I tried to hook up my little lab power
supply to drive the module back to positive, but is
instantly smoked (i guess it wasn't reverse polarity
protected).
so, now I am trying to figure out what smoked. Can you
help ? I am mostly a chemical/mechanical type, but I
understand electronics and can work a multimeter or
scope. And I am interested to learn.
The power supply is a basic bench top 0-30 V, 3A
supply. It is one of those 'sort of' standard
transformer based lab power supplies (30V, 3A) with
individual voltage a current adjustment knobs. It is
made by Electro Industries and has a part number Digi
35A. But i doubt that matters much, since i am
guessing these types of supplies are all similar. It
seems like there is a transformer, a bunch of control
circuits, some display circuits, a couple solid state
switches (are they fets ?).
Anyway, the symptoms are : the power supply still
turns on, but the display comes up and i can turn the
current up and down, but the voltage stays at .2 V no
matter what. any ideas about how to fix this ?
when the supply fried, i saw just a tiny wisp of smoke
come out of the supply. It seemed like it came from an
area in the case where there are not a lot of
components, so I thought I would start there to see if
I could find a bad part. There are two main parts in
that area. One is a capacitor (labeled 63 V, 3300uF),
the other is a solid state switch (fet?) that is about
1/2 in squared and is heat sinked to the base of the
supply. Neither looks obviously burned.
so my question, how can i test those individual
devices ? Is there something I can do with a
multimeter to see if the Cap is ok ? My DMM has a
setting for CAP, but i have never used it. what is the
failure mode for a cap anyway ? shorted ? loss of
capacitance ?
what about the 'switch' ? It has four leads coming off
it and two of them appear to be tied to together by a
resistor (R-Y-Br-R; is that 240 ohm?). Should I assume
those two are the 'coil' and the others are the
contacts ?
anyway to check to operation of this device ?
Finally, at the back of the supply there are two
circular discs mounted on a big heat sink. They look
like thermal snap discs or something, and have part
number " Greaves Limited 2N3055HV" printed on them ?
What is the function of these ? They both read 'open'
between the pins, which seems odd if they are over
temperature protection (since it is about 40 degrees
in my garage today).
anyway, i realize this is a touch OT, but this supply
is my EV battery comissioning supply, and i know there
are electronics experts on this list and I hope one of
you is patient enough to help me learn some of this
stuff.
i am most grateful for your help.
~fortunat
__________________________________________________
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--- End Message ---
--- Begin Message ---
That was the page I was looking at when I realized there could be a
problem. What it doesn't give me is information about how the side
posts are going to fit together with the next battery.
Thanx,
Paul G.
On Apr 8, 2006, at 7:30 PM, Ryan Bohm wrote:
This page might help.
http://www.evsource.com/faqs/batteries/orbital_dimensions.php
-Ryan
Could someone please stack 3 of the Exide 34XCD batteries long side
together and facing the same way and provide me the length at the
bottom (lugs)? I'm not quite sure how the side posts will affect the
length when placing them together in a row. Hopefully they will fit
in the EV Buggies current in floor battery boxes. If they only miss
by the bottom lugs I could remove one from the first and last
battery. I only have 20.40 inches to work with at the bottom of this
box (it was sized for Optimas.) I don't have to worry about extra
hight or length at the top, there is plenty of room up there.
Thanx,
Paul G.
--- End Message ---
--- Begin Message ---
The Saab weighs 3200 lbs and I would like to stay under 2500 for my
starting vehicle.
I'm leaning toward the Toyota Pickup with Phil Knox's aerodynamic mods
that reduce the Cd from 0.44 to 0.25. Which would bring the CdA to
7.0. Smoother than the Saab and less weight.
Are there other candidates?
Peter VanDerWal wrote:
THanks, Stefan.
I'd meant to mention that CdA was a more important measurement, but I
couldn't find any good info on the frontal area of the vehicles in
question (and using posted hight & width is highly misleading)
I was kind of wondering about the Camry. I still think a Saab might make
a better candidate since it seems to me they have a better load handling
capacity than the Porsches, and close to the same CdA.
I wonder what the CdA would be for a Porsche 914? As I recall the Cd
wasn't all that great, but it seems to me that it has even less frontal
area than a 911.
Indeed:
http://www.mayfco.com/tbls.htm
These charts indicate much lower Cd*ft2 numbers for the Porsche line,
BTW. They use manufacturers frontal area specs. I think the width and
height of curvy cars like this leads to gross overestimations of frontal
area. AKA a circle has less area then a square...
Porsche 911 6.27
Porsche 944 6.96
Toyota Camry 7.57
Saab 900 7.10
My personal favorites:
68 Toyota 2000GT 5.76
90 Nissan 240SX 5.88
~ Peanut Gallery ~
--- End Message ---
--- Begin Message ---
Ummm Why??
Remove the Dead corpse and get on with life.
Getting home is a matter of jumping out the weak or the blown.
Also 1200 amp diodes are not that easy or cheap to come by.
By the way it wouldework.
Do the right thing get rid of the bad one.
Madman
----- Original Message -----
From: "Seppo" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, April 09, 2006 1:41 AM
Subject: Re: Orb Carnage....
> What would happen if you simply connected a (very sturdy) diode in
> parallel with each battery? If the battery cannot keep in pace with
> the others and starts to go negative, the diode would start
> conducting the load current past the battery when the battery voltage
> is down to -0.7 V.
>
> Seppo
>
>
> Jeff Shanab kirjoitti 8.4.2006 kello 19.16:
>
> > I just had a strange idea/question. Could the concept of a bypass
> > regulator be used in another way
> >
> > disclaimer, this would be a really good way to waste money.
> >
> > Could a bypass be made that bypasses a battery when too much
> > current is
> > asked from it?
> >
> > like you have one battery in the string that can't keep up under hard
> > accelerations so it is shorted in such a way not to short the batttery
> > itself, an anolog version would be a SPDT relay which would drop
> > out if
> > the voltage dropped below a threshold.
> >
> > Your pack voltage would take a 12V hit but you keep going. Would this
> > get you down the dragstrip faster than having a low voltage sensor
> > pull
> > back the current on the controller?
> >
> > Now in a system of 25 12 volt cells, this is probably not much use,
> > but
> > if I have 100 li-ion cells, or 1000s of D-cells this might become more
> > resonable.
> >
> > could a bypass be made that lets the battery still contribute?
> >
> > B1--200A---B2--100A----B3----200A---...
> > |_____100A__|
> >
> >
> >
> >
> >
>
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--- Begin Message ---
The Manzanita Micro Mark 2 Regs use a NTC thermistor and a analog set point
The Mk3 Regs use a Lm34 Temps sensor.
No I am not handing out schematics...
Madman
----- Original Message -----
From: "Mike Phillips" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, April 09, 2006 10:30 AM
Subject: Thermal measurements
> Has anyone measured their battery temperatures? Just curious what you
> used and what numbers you got in various conditions.
>
> I'm secretly hoping for proven schematic with part numbers cause I'm
> buried right now.
>
> But even meat thermometers qualify to answer the question.
>
> Mike
>
>
>
> Here's to the crazy ones.
> The misfits.
> The rebels.
> The troublemakers.
> The round pegs in the square holes.
> The ones who see things differently
> The ones that change the world!!
>
> www.RotorDesign.com
>
--- End Message ---
--- Begin Message ---
Disclaimer: I'm just brainstorming here. I have no experience or
expertise or EE degrees. Pay attention to me at your peril!
On Apr 9, 2006, at 8:37 AM, Lee Hart wrote:
Jim Husted wrote:
Also I don't think you could braze the bars together as they would
all
short,
Doug Weathers wrote:
That's the point - you want them all shorted together to form one
continuous conductor. A slip ring.
Yes, but you don't have room for 3 of them.
You could slice the comm in half or thirds (losing the ability to use a
stock brush holder and stock brushes), or you could simply stack three
end bells on a lengthened shaft. The resulting kludge would be quite a
bit longer than a stock motor, but the Siamese 8 suggests that this
isn't necessarily a big problem.
besides the melt factor to the bake-a-lite the coms made out of.
I thought bakelite was sturdier than that.
Jim's right; it would be damaged by brazing temperatures.
My bad, I was wrong. Thanks for the correction Jim and Lee.
Then just solder the wires all together, one to the next. Presto, a
slip ring. No arcing - they'll all be at the same potential. This
sounds very easy to me.
That just gives you one slip ring. You need three. Well, 2 would work
for a single-phase winding. But if you're going to all this trouble,
you
migth as well use 3 to get the benefits of 3-phase.
I know that using commutator assemblies as slip rings is far from
optimal. The point of this suggestion is that Jim can slap it together
using the stuff in his shop (excepting the long motor shaft, which he
has demonstrated an ability to procure).
I'd opt for a press on coller over the brazing if in fact that would
work 8^ ).
It would work. If you can find a high-conductivity tube with the
correct inside diameter, that would be great. It increases the
diameter of the "comm", so it might not work out as well with stock
brush assemblies.
The slip rings should have a pretty big cross section, both for
strength
to withstand high rpm, and to carry significant current (you could
easily pull 100+ amps from them). It's likely to be pretty difficult to
find 1/4" thick tubing to cut them from.
This is another good reason to make a slip ring out of a commutator.
They have a demonstrated ability to handle high currents and motor
voltages and motor RPMs. There's one at the other end of the motor!
<snip Lee's suggestion on how to build a custom slip ring assembly>
I'm sure that a purpose-built slip ring assembly would take up less
room, and would definitely be the choice for a production version.
What I'm proposing is a proof-of-concept demonstrator that can probably
be put together relatively quickly, out of proven parts that are
already in stock (except for the shaft). Also, since Jim didn't know
about slip rings, I thought that providing an example built out of
familiar parts would be educational. This rationale is now obsolete.
If the effort of designing, building, and debugging a custom slip ring
assembly is trivial, then my kluge suggestion is not worth pursuing.
But if the kludge could be put together quickly, with a low cost and a
high confidence that it would work, it would allow you to start testing
the rest of the regen system sooner.
In fact, standing back and looking at the whole concept, why are we not
considering shunt motors?
I'm done now, go back to what you were doing :)
--
Doug Weathers
Bend, OR, USA
<http://learn-something.blogsite.org/>
--- End Message ---
--- Begin Message ---
Hello Mike,
To read my battery pack temperature on the go, I'm using a temperature
sensor that is design for the Link-10 E-meter.
It is a two wire temperature sensor that connects to the No. 6 and No. 8
terminal strip on the back of the Link-10. The part No. for this sensor is
1N2535.
The sensor is bolted on any one of the battery post. The temperature prod
is imbedded in side a wire lug and isolated from any metal of the wire lug.
The wire lug is than either bolted to a extended battery post clamp or a
battery stud.
This morning, in Great Falls, Montana, it was 40 degrees F. Inside my
garage the on wall temperature is 65 degrees F. I turn off the heating
system for the winter, but I have a super high R-factor insulation that is
80 R's for the wall and 140 R's ceiling and a garage door of 20 R's, so it
maintains this temperature for a long time and even into the summer.
The battery pack is also in a super insulated battery box, so even after
driving the EV, it will hold the battery temperature range from 62 to 65
degrees.
This morning when, the battery temperature was at 17 degrees C. or 62.6 F.
Driving for one mile at 50 battery amp, the temperature rose to 18 degrees
C. or 64.4 F. After letting the EV set one hour in a outside ambient
temperature of 40 F. the Link 10 still had a read out of 18 C. It may be
between 17.5 and 18 C.
This is with a 260 AH battery pack that weighs more than a ton. A smaller
pack at a lower AH will increase in temperature faster and lose the
temperature quicker.
Driving home for another mile at 50 battery amp the battery temperature
still read 18 C. Letting the EV set for 20 hours, the temperature will be
down in the 17 C. range or about 62+ F.
If you battery pack is un-insulated, then the battery post will be the same
temperature as the ambient air very quickly.
To read the temperature on a Link-10, press F3 for a read out.
Before I had a Link-10, I used a small battery operate temperature gage made
by ACURITE which you can get from WalMart. It has a 10 foot cable and
sensor, normally for reading outside temperature from inside you house. I
used many of these sensors, when I was building my high R-Factor house, for
testing the floor to ceiling and inside wall to outside ambient temperature.
I normally keep my battery pack in about the 65 degree range all winter
long. In summer, the battery back temperature is between 70 and 75 F. I do
not drive that far, so I do not have to squeeze every AH out it. I get
about 2000 cycles out of my batteries, because I at 80% capacity about 95%
of the time. For me this is about 100 cycles per year or would be 20 years.
I normally get 10 to 12 years out of a battery pack.
Roland
----- Original Message -----
From: "Mike Phillips" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, April 09, 2006 11:30 AM
Subject: Thermal measurements
> Has anyone measured their battery temperatures? Just curious what you
> used and what numbers you got in various conditions.
>
> I'm secretly hoping for proven schematic with part numbers cause I'm
> buried right now.
>
> But even meat thermometers qualify to answer the question.
>
> Mike
>
>
>
> Here's to the crazy ones.
> The misfits.
> The rebels.
> The troublemakers.
> The round pegs in the square holes.
> The ones who see things differently
> The ones that change the world!!
>
> www.RotorDesign.com
>
>
--- End Message ---
--- Begin Message ---
I talked to Danny Saturday afternoon & he said the car wasn't yet running.
He must have gotten it going Saturday evening. Good job. As far as the
Gear box I saw when the motor came out I liked it. I don't know how it runs
but it is small and puts the motor in a nice place to extract. Is there
some issue worth discussing here? Lawrence Rhodes.
----- Original Message -----
From: "Will Beckett (becketts)" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, April 09, 2006 12:03 AM
Subject: RE: [solectria_ev] A Force broken in San Francisco Back on the Road
Good to hear. Any word about making improvements to the gearbox based on
what you found?
- Will
323 Los Altos Drive
Aptos, CA 95003
(831) 688-8669
http://becketts.ws/Will
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Danny Ames
Sent: Saturday, April 08, 2006 8:46 PM
To: [EMAIL PROTECTED]; EV SEND MSG; SFEAA
Subject: Re: [solectria_ev] A Force broken in San Francisco Back on the
Road
Wanted to share my good news.
Just completed the final repair work today and its working great.
With all the rain storms here in soggy California and my limited time
available to work on the car it has been a challenge.
Fortunately I was able to get a new sensor and get the motor in and out ok
between dry times.
Motor bearings were replaced due to excessive axial play.
The sensor board was also bad due to it getting banged.
Runs like a top.
Danny
Danny Ames wrote:
After several months of carefree driving we have now been down for
several weeks.
I have bee reluctant to post my story and a bit depressed and needed to
do some checking.
In my several calls to various people feel ready to run this by those
on the list.
What happened is the car starting bucking on de-acceleration and got
progressively worse till finally it stopped moving in downtown rush hour.
I examined the speed sensor disk and could see the lines scratched off
where the detector pair on the speed sensor is placed.
I re-inked the disk lines with a sharpie and tried to makes several
adjustments but could not get it going at all and had the car towed home.
Jacked up the front end so the wheels could turn freely.
Completely backed off the sensor and the motor would turn smoothly and
slowly.
In testing I adjusted the sensor closer in small increments to the disk
and then the motor started to respond in a very erratic and rough
stepping motions. The axial motion of the motor armature starting
jumping about at what appears to be .125 inch so the disk is moving to
and fro in this sputtering effect to the sensor and is very choppy The
motor bearings seem noise free but the armatures axial movement maybe
to great and the trouble possibly.
When the motor is at rest the disk is about flush to the motor face.
I can see the motor mounts with 3 bolts, so does one remove these and
simply slide the motor out.
Also how does the motor shaft engage to the transmission?
Hopefully I am on the right track to fixing this.
Danny
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/solectria_ev/
<*> To unsubscribe from this group, send an email to:
[EMAIL PROTECTED]
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
--- End Message ---
--- Begin Message ---
For one thing you have to join your group to read the message. I still
couldn't find what you are talking about. Where are you located? Lawrence
Rhodes....
----- Original Message -----
From: "multi-Timm" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, April 09, 2006 8:59 AM
Subject: the $5000 car - could use some expert help
We are well into the development of our $5000 kit car that pretty much
anyone can afford. It can be assembled as an EV or a hybrid, depending on
whether the owner prefers a generator or more batteries in it's place.
We're well covered on mechanical and design, but we do lack some
EXPERIENCED experts in electrical. Currently there are only one or two
guys who are expert and doing all the pulling in electrical, so the group
could use an extra person or two on the team. If anyone is interested,
you are most welcome to join us.
Hope to see you there:
autos.groups.yahoo.com/group/SmallEfficientVehicles/members
Timm
http://autos.groups.yahoo.com/group/SmallEfficientVehicles/members
T!MM! §
http://www.nrdc.org/wildlife/marine/nlfa.asp
http://groups.yahoo.com/group/Inventors-World/
http://groups.yahoo.com/group/CADoutsourcing/
http://autos.groups.yahoo.com/group/SmallEfficientVehicles/
"We don't see things as they are, we see them as we are" (Anaïs Nin)
---------------------------------
Enrich your life at Yahoo! Canada Finance
--- End Message ---
--- Begin Message ---
I thought I might have come up with a simple regen for the series motor
during lunch but I am afraid that I came up instead with a problem for
both scenarios.
We generally step the pack down, so unless we step it up how can we
charge the pack. There is an argument for the AC slip ring, It can be
easily stepped up.
but food for thought, look at this :
B+______________________________________________
| __|__
| /_\ D1 ____
| | / \
| _______ o____|________A1__[
]__A2______B-
|__B+_| zilla |M+___S1-field--S2___o==== K1
\____/ |
|_______|________________________o_________________________________|
||
__||____
|hairball|
|________|
| |
|-----|-----------|
/\/\/\/------------/\/\/\/-
PB6 throttle PB6 brake
12V----NO----------------NC-------------------K1coil-----gnd
D1 - SD1053C18S20L $127 at digikey 1000A 1800V diode
K1 - SPDT SW201 $175 evparts (would this be lrg enough?
Intended theory of operation:
During motoring K1 is in the NC position connected to A1 and current
flows from the zilla thru the field then the armature to pack neg.
D1 is reverse biased so it doesn't allow battery to feed arnmature.
When the throttle is released the NO switch on the throttle pot-box
closes and when the user presses on the brake pedal, a second potbox is
used. The NC closed switch is allowed to close as the braking throttle
is applied. K1 is pulled in and current begins to flow from zilla thru
the field to pack negative.
This fixed field is crossed by the armature coils and voltage is
producted and mechanically rectified byt the existing commutator.
This voltage, if high enough will cause D1 to conduct and push DC into
the Pack. since k1 has isolated A1 from the ground or the field.
How do I now make a DC-DC converter that can handle this or do I use a
second low voltage pack(cap bank?) that feeds a dc-dc slowly to recharge
the pack.
--- End Message ---
--- Begin Message ---
Might be better for Danny to describe this but in basic terms, there is a
lot of stress at the worm gear connection to the gear box. This causes an
increase in the amount of play on the motor shaft and that will cause the
speed sensor to freak out. In Danny's case, the car stopped and wouldn't
start up again.
- Will
323 Los Altos Drive
Aptos, CA 95003
(831) 688-8669
http://becketts.ws/Will
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Lawrence Rhodes
Sent: Sunday, April 09, 2006 12:54 PM
To: Electric Vehicle Discussion List
Subject: Re: [solectria_ev] A Force broken in San Francisco Back on the Road
I talked to Danny Saturday afternoon & he said the car wasn't yet running.
He must have gotten it going Saturday evening. Good job. As far as the
Gear box I saw when the motor came out I liked it. I don't know how it runs
but it is small and puts the motor in a nice place to extract. Is there
some issue worth discussing here? Lawrence Rhodes.
----- Original Message -----
From: "Will Beckett (becketts)" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, April 09, 2006 12:03 AM
Subject: RE: [solectria_ev] A Force broken in San Francisco Back on the Road
> Good to hear. Any word about making improvements to the gearbox based
> on what you found?
>
>
> - Will
>
> 323 Los Altos Drive
> Aptos, CA 95003
>
> (831) 688-8669
> http://becketts.ws/Will
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
> On Behalf Of Danny Ames
> Sent: Saturday, April 08, 2006 8:46 PM
> To: [EMAIL PROTECTED]; EV SEND MSG; SFEAA
> Subject: Re: [solectria_ev] A Force broken in San Francisco Back on
> the Road
>
> Wanted to share my good news.
> Just completed the final repair work today and its working great.
> With all the rain storms here in soggy California and my limited time
> available to work on the car it has been a challenge.
> Fortunately I was able to get a new sensor and get the motor in and
> out ok between dry times.
> Motor bearings were replaced due to excessive axial play.
> The sensor board was also bad due to it getting banged.
> Runs like a top.
> Danny
>
> Danny Ames wrote:
>
>>After several months of carefree driving we have now been down for
>>several weeks.
>>I have bee reluctant to post my story and a bit depressed and needed
>>to do some checking.
>>In my several calls to various people feel ready to run this by those
>>on the list.
>>What happened is the car starting bucking on de-acceleration and got
>>progressively worse till finally it stopped moving in downtown rush hour.
>>I examined the speed sensor disk and could see the lines scratched off
>>where the detector pair on the speed sensor is placed.
>>I re-inked the disk lines with a sharpie and tried to makes several
>>adjustments but could not get it going at all and had the car towed home.
>>Jacked up the front end so the wheels could turn freely.
>>Completely backed off the sensor and the motor would turn smoothly and
>>slowly.
>>In testing I adjusted the sensor closer in small increments to the
>>disk and then the motor started to respond in a very erratic and rough
>>stepping motions. The axial motion of the motor armature starting
>>jumping about at what appears to be .125 inch so the disk is moving
>>to and fro in this sputtering effect to the sensor and is very choppy
>>The motor bearings seem noise free but the armatures axial movement
>>maybe to great and the trouble possibly.
>>When the motor is at rest the disk is about flush to the motor face.
>>I can see the motor mounts with 3 bolts, so does one remove these and
>>simply slide the motor out.
>>Also how does the motor shaft engage to the transmission?
>>Hopefully I am on the right track to fixing this.
>>Danny
>>
>>
>>
>>
>>
>>
>>
>>
>>Yahoo! Groups Links
>>
>><*> To visit your group on the web, go to:
>> http://groups.yahoo.com/group/solectria_ev/
>>
>><*> To unsubscribe from this group, send an email to:
>> [EMAIL PROTECTED]
>>
>><*> Your use of Yahoo! Groups is subject to:
>> http://docs.yahoo.com/info/terms/
>>
>>
>>
>>
>>
>>
>
--- End Message ---
