EV Digest 5512
Topics covered in this issue include:
1) Re: MOSFETs vs. IGBTs
by "Joe Smalley" <[EMAIL PROTECTED]>
2) Re: 200 miles highway range on flooded lead acid: Is it possible?
by David Dymaxion <[EMAIL PROTECTED]>
3) Re: New Netgain TransWarp 11
by "steve clunn" <[EMAIL PROTECTED]>
4) A bad week for EVs (was: Re: Ampabout, Joliet Version)
by "Paul G." <[EMAIL PROTECTED]>
5) Re: Ampabout, Joliet Version
by "Michael Perry" <[EMAIL PROTECTED]>
6) Re: Edison batteries
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
7) Re: AC vs. DC - hopefully ending (for now...)
by Victor Tikhonov <[EMAIL PROTECTED]>
8) 5th EVer Chapter Conference Photos
by Peter Eckhoff <[EMAIL PROTECTED]>
9) Re: Regen - as a 'brake'
by "peekay" <[EMAIL PROTECTED]>
10) RE: Regen - as a 'brake'
by "Don Cameron" <[EMAIL PROTECTED]>
11) Re: Valence
by Meta Bus <[EMAIL PROTECTED]>
12) Re: G'bye Porsche...
by "Mark Grasser" <[EMAIL PROTECTED]>
13) Re: Taperlock dilemma
by Dave Cover <[EMAIL PROTECTED]>
14) Re: G'bye Porsche...
by Lee Hart <[EMAIL PROTECTED]>
15) Re: Taperlock dilemma
by Jim Husted <[EMAIL PROTECTED]>
16) Re: Aerodynamics .. viktor's idea .. to reduce 'drag' to near zero
by Lee Hart <[EMAIL PROTECTED]>
17) Edison batts
by "Mike Phillips" <[EMAIL PROTECTED]>
18) Re: MOSFETs vs. IGBTs
by Lee Hart <[EMAIL PROTECTED]>
19) Re: Taperlock dilemma
by "Roland Wiench" <[EMAIL PROTECTED]>
--- Begin Message ---
IGBTs switching losses produce more heat. They need to dissipate more heat
to pass the same amount of current at the same frequency and duty cycle.
IGBTs do not share current as well as MOSFETs. The IGBTs need to be derated
more to compensate for the imbalance.
Joe Smalley
Rural Kitsap County WA
Fiesta 48 volts
NEDRA 48 volt street conversion record holder
[EMAIL PROTECTED]
----- Original Message -----
From: "Brad Baylor" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, May 18, 2006 11:11 PM
Subject: MOSFETs vs. IGBTs
> Otmar recently stated that when using over 144V nominal that IGBTs
> were better. But some calculations I did leave me confused.
>
> Given a 20 12 V Orbital battery system (192 V):
> Losses for a racing controller using 20 paralleled devices (package
> limit is 100 A per):
> Ixys IXGN 60N60 1.7 VCE 600 V IGBTs:
> 1.7 V x 2000 A = 3400 W
> 1.7 V x 1000 A = 1800 W
> 1.7 V x 500 A = 850 W
> 1.7 V x 100 A = 170 W
> 1.7 V x 50 A = 85 W
>
> Ixys IXFN 130N30 22 mohm 300 V MOSFETs:
> .0011 ohm x 2000 A ^ 2 = 4400 W
> .0011 ohm x 1000 A ^ 2 = 1100 W
> .0011 ohm x 500 A ^ 2 = 275 W
> .0011 ohm x 100 A ^ 2 = 11 W
> .0011 ohm x 50 A ^ 2 = 2.75 W
>
> Losses for a more typical controller with 10 paralleled devices:
> Ixys IXGN 60N60 1.7 VCE 600 V IGBTs:
> 1.7 V x 1000 A = 1800 W
> 1.7 V x 500 A = 850 W
> 1.7 V x 100 A = 170 W
> 1.7 V x 50 A = 85 W
>
> Ixys IXFN 130N30 22 mohm 300 V MOSFETs:
> .0022 ohm x 1000 A ^ 2 = 2200 W
> .0022 ohm x 500 A ^ 2 = 550 W
> .0022 ohm x 100 A ^ 2 = 22 W
> .0022 ohm x 50 A ^ 2 = 5.5 W
>
> The IGBTs only appear to have an advantage at racing current levels.
> For normal driving, MOSFETs seem the better choice, especially
> considering that matching devices is unimportant. What does voltage
> (144 V) have to do with anything? Yeah I know the RDSon for 600 V
> MOSFETs sucks, but voltages like that aren't used for typical DC
> conversions. Desired current levels seems to be the important
> parameter in deciding which to use.
>
> Are switching losses lower with IGBTs? Are IGBTs better suited to
> handling accidents and abuse? What I'm I missing?
>
> Curiosity is killing this cat.. :)
> Brad Baylor
>
--- End Message ---
--- Begin Message ---
200 miles with a production car donor chassis would be pretty
challenging. With a custom car, though, I'd think it would be doable.
Start the thought process with Tango
(<http://www.commutercars.com/>), but make it twice as long and 1/2
as high. Put in 2 or 3 times as many batteries. Now you basically
have a Salt Flats streamliner <http://www.landracing.com/> -- but is
probably better aero Cd than most any car and less than 1/2 the
frontal area.
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: "Roland Wiench"
I using a Warp 9 as a temporary motor, and it does not have the
performance of the 11.> Roland
----- Original Message -----
From: "steve clunn" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Wednesday, May 17, 2006 8:24 AM
Subject: Re: New Netgain TransWarp 11
----- Original Message -----
From: "Pestka, Dennis J" <
Hi Pastka and all
I have a warp 11 in one of my ev's that I had a 9 in before , , here is
a
video clip of it spinning the tires , while in 4th gear right tire dose
most
of the spinning .
http://www.grassrootsev.com/mits.htm . From a dead stop the truck feels
faster in the take of in 4th that in 3 ed , I know this doesn't seem to
make
allot of sense , but that's the feel I get from it .
The motor data sheet say 2 times the toque as their 9" for the same amp
and
volts , this of course means 1/2 the rpm and makes 3ed gear feel like 1st
with a 9" and 4th gear which one would never take off in with a 9" feels
like 2ed . I put some bigger tires on , and was smoking the tires for a
reporter when the tranny started making a noise . I'm planning on hooking
the motor right to the rear now.
I took the 2k zilla out and put it in pauls 959 Porsche
http://www.worldclassexotics.com/ which also has a 11 net gain motor . We
went for a test drive and after a bit started smelling what at first
smelled
like burning insulation , motor was cool , turned out to be the clutch .
Yes
a 911 stock clutch will not handle the torque , not even close .
>
> Would one motor reduce the number of contactors needed to supply
> reverse?
>
could be done with one set of reversing contactors ( 2 contactors hooked
together )
> Can a series/parallel setup still be done with 1 motor?
Their 13 " motor has this for the field windings, but right now the 11
dose
not . I'm running a 3.7 rear and even with some big 285 /15 it will
still
spin the wheels in 4th gear, but at about 70 mph the battery amp start to
drop and it feels like its time to shift , this is where the series/
parallel would come in so as to get more power out of the controller , or
if
I had a 5 th gear . If you don't have room for 2 motors ( 8's or 9's )
than
one 11 will let you experience the power of a 2k zilla but you will have
to
deal with 2 times the toque .
I'd like to hear from some other 11 motor users also , are you finding
the same things I'm seeing ?
Steve Clunn , thinking about 2 11" , :-)
> Does it gain you anything?
>
> Sorry for all the questions;
> Dennis
>
>
--- End Message ---
--- Begin Message ---
Wow, its been a tough week for EVs. First I learn that Michael
Bearden's Porsche visited hell. Now I hear the Bob Rice's Rabbit turned
into more sled than lead.
I'm sorry for your losses. Its not easy seeing one's hard work turned
into junk.
Paul "neon" G.
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: <[EMAIL PROTECTED]>
> OK MY turn! I figgured that I would just drag my E brake and wheelslip a
bit before my clutch would let go. But in second gear, revving the motor up
with the T Wrecks, dumping the clutch, it broke loose into a 500 amp plus
wheelslip! Tires spun, and SPUN! Gees a 3 million lb Floody powered non
racing setup, doing the smookiest burnout I have EVer gotten!Turning the
steering wheel right an' left got BOTH tires smoking. As they sang and
ground along filling the cabin with smoke I could see 350 amps with a 15
volt sag on the 120 volt system, about what it takes to go about 85 mph in
5th! I was sorta waiting for SOMETHING to open up in a blinging flash? Take
yur pick, battery terminals, fuze, motor flashover/ Or just killing the
controller.
> Bob
Geez, Bob. Here it was midnight as I was reading your tale... and had
reached this point. Here I am, expecting your controller to blow, when
there's an explosion in the house... like a Cherry bomb, or a 38 blank,
going off in the house. (How'd you plan timing like that?)
No big deal, just an exploding tire in the entryway... but so perfectly
timed that now, half an hour later, my heart is coming back down and the
dogs are finally calmed down. (They expect this sort of thing, I guess...
but they are at my feet, instead of in the other room.)
A few years ago, Bikerev built me a custom battery trailer for one of my
toys... the e-bike. It's been sitting for a while and I need a couple of the
Hawkers for my e-mower. I aired up the tires, pulled it out to an outlet and
threw on the 48V charger. I got to this part of your story, and Blam! The
dogs, asleep in the next room, go running, looking guilty, and my heart is
racing. My first thought was I'd fried/blown a batt, but they aren't even
warm after an hour. I looked around to see if maybe a sheet of something
fell to the floor, but the remodel is past having sheets of subflooring in
the house. It turns out one of the tubes on the trailer blew so hard it knoc
ked the tire off the rim. I'd have not thought 45 lbs could make that much
noise on a 16" bike tire.
What a heart stopping coincidence. It certainly made your tale a whole lot
more interesting and personal. <g> BTW, I'm sorry to hear about the loss of
your car. It's good in a way, I guess... now you get to build your Jetta,
eh? Those same roads nearly took out my new car, in the same way, when I was
moving west. Fortunately, a trucker warned me in time. My tow hitch was
broken on one side and when I touched it, it fell off... so I can sorta
relate.
--- End Message ---
--- Begin Message ---
My friend who works for the Department of Electricity in San Francisco
plucked up the UPS batteries many years ago that powered the Fire Alarm
system during a power outage when they were replaced. If you are interested
I can get you in contact. They are about 18" high and 1.2 or so in voltage.
Lots of capacity Probably good for a solar system or low speed vehicle
like a parade float. Lawrence Rhodes.....
----- Original Message -----
From: "Mike Phillips" <[EMAIL PROTECTED]>
To: "Lawrence Rhodes" <ev@listproc.sjsu.edu>
Sent: Saturday, May 20, 2006 12:26 PM
Subject: Re: Edison batteries
Lawrence,
Who are you refering to? I'm in SJ.
Mike
--- In [EMAIL PROTECTED], "Lawrence Rhodes" <[EMAIL PROTECTED]> wrote:
I know a guy in the Bay Area with a bunch of the Edison cells. I
bet he'd
give them to you. Lawrence Rhodes.....
----- Original Message -----
From: "Michael Perry" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Friday, May 19, 2006 5:49 PM
Subject: Edison batteries
> You can sometimes find them for sale on the EV sites. There were
several
> auto batteries available, about 4 years ago, on one of the EV For Sale
> sites. The only thing EBay has today is the wooden box 4 of these
cells
> were
> kept in.
>
http://cgi.ebay.com/1890s-EDISON-LALANDE-Type-S-4-cell-battery-box_W0QQitemZ6279865096QQcategoryZ414QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
>
> You might also contact this dealer that scraps Edison batts. They
insist
> that the batts be stripped of their contacts and wooden crates,
but might
> guide you to someone.
> http://www.recycle.net/specs/gr030560.html
> The Edisonian might also know something about where to find them
> http://www.edisonian.com
> I've also read that a Chinese company (and one in Europe???) is making
> replacements.
>
> They weren't used in all that many autos, but were popular for
industrial
> uses, due to their long life and relatively light weight per watt
> (compared
> to LA of the time.) Apparently the 1.3V required too many cells,
and their
> maintenance/weather profile, made them not the best for mobile
> applications.
> (Though I understand some forklifts and heavy trucks may have used
them.)
> They were critical to be kept maintained & didn't do well in the
cold...
> and
> hydrogen offgassing during charging doesn't make them overly popular.
>
> These can often be rebuilt today, 100 years after they were built,
I'm
> told.
> (Jay Leno's car has the original batts.. or at least the original
cases...
> and uses it to drive his car around.) You'll see a lot of bottles
for sale
> "Edison Battery Oil". That oil was dumped atop the batts, floating, to
> minimize evaporation.
>
> "Another widely used secondary cell is the alkaline cell, or
nickel-iron
> battery, developed by the American inventor Thomas Edison in the
1900s.
> The
> principle of operation is the same as in the lead-acid cell except
that
> the
> negative electrode consists of iron, the positive electrode is of
nickel
> oxide, and the electrolyte is a solution of potassium hydroxide. The
> nickel-iron cell has the disadvantage of giving off hydrogen gas
during
> charging. This battery is used principally in heavy industry
applications.
> The Edison battery has a useful life of approximately ten years and
> produces
> about 1.15 V."
>
> ----- Original Message -----
> From: "Mike Phillips" <[EMAIL PROTECTED]>
> To: "Andre' Blanchard" <[EMAIL PROTECTED]>
> Sent: Friday, May 19, 2006 12:59 PM
> Subject: Re: Question about NIMH patent(s)
>
>
>> I'd love to disect an original Edison battery. I think they were in
>> metal cans?
>>
>> It's clear that the energy density is not as good as lead acid, but
>> then again, maybe that can be changed.
>>
>> Mike
>
--- End Message ---
--- Begin Message ---
I'll skip forward to technical part
Otmar wrote:
I reiterate my point: A logical controller for comparison would be the
Z1K-LV (which is still quite a bit less expensive than the Z1K-EHV which
you chose). The Z1K-LV package costs $1975 which is $850 less than the
one you used for your comparison.
The reason I choose HV version is simply because inverters are also HV.
HV to HV seem apples to apples to me. HV AC compared to LV DC is not
quite the same, even though LV DC still makes more raw power.
Reason: if AC system uses more expensive silicon and caps and other bits
and pieces, and customer gets benefits for this extra expense, for
comparison reason you also add such components and also add some extra
cost. That way units are as alike as possible.
The fact that HV may not be nessessary for practical car conversion
is *irrelevant*. If we start discuss what best for a particular
car, much more will be involved than just a controller.
We compare drive systems. I can't (and don't want to) change
configuration of the system, it comes that way and prices as whole.
You provide just a controller, so to get as close as possible
to the identical system *just for price comparison) you just use
identical components (other than controller itself).
If you don't use identical other components (again, may be better for
practical conversion), of course price will be different too and
co longer apples to apples. It becomes as everything else: you
get what you paid for.
So, if you compare HV inverters to LV controllers, granted you pay
less for LV controller (and yes get more raw power) but you also get
only LV controller e.g. no HV advantages, whether you need these
advantages or not).
I'm sorry Victor. But I must call you on that statement. Did you intend
it to sound as misleading as it sounds to me? "Identical" as I
understand it, means something which is "similar in every detail".
As identical as you can choose. You can't reap out half of the power of
zilla (and recalculate reduced price) to get it closer to 100-150kW
typical inverter offers, you don't make any lower power ones. So we must
use lowest power you do make.
But you do make LV and HV versions, and I only offer HV.
HV cost money. Naturally, we must compare HV to HV then,
if you want to compare dollars, *even* though this leads to yet
more power of DC controller. IF primary criteria though is power,
you sure should stay with LV DC system. However, max power per
dollar is not where AC shines, and not the goal, there is no secret.
So what is the most reasonable way to compare two systems? When
comparing drive systems it is common to compare power ratings. Don't
worry, I'm not trying to say we need to do that, I will be the first to
admit that my lowest power controller has more power than most people
need. So for most people the power difference between your 78kW drive
and my Z1K-LV is unimportant. Power ratings are broken down into
voltage and current ratings. Some controllers get their power ratings
from high voltage since on the controller side of the system it is less
expensive to do it this way. Comparing the voltage alone, and ignoring
the current or power rating, as you have done seems unreasonable to me.
I think it would be reasonable, when comparing the cost of systems, to
compare your 78kW system to my least expensive system. Does this not
seem logical to you?
Yes it does, provided that this statement "When comparing drive
systems it is common to compare power ratings" is indeed a top priority
for someone who compares. "Most common" I take as majority of
people (potential buyers), is that what you mean?
So then for these people power/$ ratio is on top of the list, and
for minority others - isn't. Just like most people drives Camry,
and some minority - Mercedes. Nothing wrong with either one.
....
As I stated: $2.3k inverter, $2.3k motor (up to supplier
to change that). Identical feature set, only low voltage (72-160V)
and proportionally lower power.
Thank you. I'm glad to hear that. It's good to see more options
available. I can see how they could be very nice in a very light car
(which we should be seeing more of with lithium batteries), but as you
admit, you don't expect to sell many since they are pretty low power...
I don't know how many, it's not up to me to decide if people have
enough power for their needs or not. You'd think that if the systems are
made by a OEM manufacturer with certain power level, they've done
their home work and chose it for real on-road EVs, so it must be enough
for *their most* potential customers. You and I may think it's not
enough for us, but if it wouldn't be enough for most, they'd never been
produced - no manufacturer knowingly will set themselves for losses.
So they decided *this* power is enough for *that* sector of buyers -
most of them will be doing commuting around European towns.
I realize Americans want everything bigger better and meaner, so such
systems well may not find too many customers.
The power for DC controller drops too - no difference.
Well, there is a difference, when you start with twice the power needed,
then you can choose to drop the power in half and still get the required
performance. It all depends on the power required.
Sure, but starting with twice the power need meaning paying for twice
the power need and if you intend to drop it in half it makes no sense.
My personal opinion
is that 50kW is as low as most people want to let it drop for a street
machine.
I suppose you mean peak power here, not continuous.
I'd agree with this for the USA situation where everyone fears to get
run over by an SUV on a freeway entry ramp and 70-75 MPH is a norm.
Carlton Brown and Gary Graunke both use 18kW rated (up to ~60kW max
but max depends on the voltage) motor. Carl uses kit car body, and Gary
has Insight. I suppose they can chime in and tell us if they feel
max power and acceleration adequate at least for them.
But there is a big difference between trying to make my own product look
bad, and trying to make someone elses' product look bad. I believe that
if you are going to publish a website that says things about the
"competition" with a critical or disrespectful attitude, then what you
say should be true and reasonable.
I have decided, I'll take out any comparisons on my business web page,
though it won't help customers. I'll move it to either ACRX conversion
page where it may be more appropriate because I've done it both ways,
DC and AC (no Zillas though :-( ), or John Lussmyer just offered hosting
of such a site.
But if you find any references to Zilla where I said they are "bad"
I'll take it out, because this is not true - they are excellent
controllers. If excellent controllers only look bad just because
compared to something even better (whatever "better" criteria might be),
well, tough luck. Same as tough luck for MES AC inverters - they are
excellent ones but look "bad" compared to top of the line of BRUSA ones.
Any street legal drag car performance look bad compared to a rail.
Are these cars bad? This is why we have classes.
I can confess outloud: in a class of DC controllers, Zillas are
the King, no comparison to any other DC controller.
OK, If I understand your point many of your customers basically have
unlimited funds.
Not true; and $8k-$10k (today) is high but not unreasonable cost
for what you get. Certainly you don't need "unlimited" funds.
Any normal car today cost 3 times of that and *everyone* has
at least one vehicle, most - more than one, and it cost them
more than $8k-$10k.
But those people don't care about price comparisons. So
I must assume that the section on your site addressing the price
comparison of AC to DC drives is intended for the same customers who buy
my product, those who find price is important.
I don't judge people and their ability to pay, I don't look in their
pockets. I do know the price is important (believe me it is
important to me as customer too), but I sell the hardware
for what I believe it worth, not how much someone can pay.
Many can't afford it. I can't afford BRUSA High speed drive either.
So what? We all want something we can't afford, guaranteed.
...
Siemens AC drive includes 60A DC-DC converter, main
contactors, "reverse contactors" (as a software function but for
comparison purposes you'd need to shell out for these), the Bosch
throttle sensor, the battery cables, the motor cables, dash
instrumentation interface all pre-wired.
Add these to your controller cost. Still $1,975??
Yes, I say my controller still costs $1975. What's so hard about that?
Nothing. You just talk about one $1975 component which needs many more
other components to make up a system. And comparing to a system.
...
It seems that on your site you knew that what I am selling is called a
"controller". You also made it quite clear that it didn't come with all
the things that your "solution" comes with. I call these other parts
accessories since they are not what is primarily controlling the motor.
No. Here is my and your quote from previous email:
---------------
This is true, but irrelevant for discussion. We are not
talking about overall building a car.
We're not eh? Ok, but I thought the whole reason of your Q and A was to
help people decide which components to use in building a car.
---------------
So if you're talking about building a car, you must include
components (and their cost) you call "accessories". If one
thinks $1975 is all he/she can get away with (+ motor) for a car,
*this* is misleading.
If you want to compare pure controller then I'd have to leave out
the cost of very expensive (not discussing reasons for it) contactors,
throttle pot, and rip out DC-DC converter which is integral part
of the inverters (and so reduce the cost accordingly). What's left
is AC analog (functionally) to the Zilla. I have no idea how much
that would cost. I get complete package. If you want to compare fairly,
you must fit other "accessories" identical to what I use, and then
compare. Because only then user gets the same quality accessories,
which makes comparison easier. Different accessories may be more
practical, but then the system is not quite the same either.
Not saying better or worse. Different. overall price must be different
too. So only for the sake of the comparison, get the same accessories.
I can give you part numbers, because this is what people is paying
and getting. And then compare.
I was addressing the part of your site where you were illogically
listing the prices of my "controllers" at $4900 and then $2850. Both of
which were well above the closest comparable unit at $1975.
I should have said "complete AC systems except the motor" then, not
just "controllers". So people know they'd need more accessories to
make up a system. I can change that, no problem, it will be clearer.
I disagree. Battery impacts everything but is not part of the
drive systems cost we're comparing. For comparison wee can both
use 24 Optimas (so the battery cost has no impact AC vs DC).
And I disagree with that choice. 24 Optimas have a very high cost per
mile and are optimized for high power. They would be better for a short
range fast car with fewer batteries.
It's irrelevant. We must choose identical components other than
inverters/controllers so the price difference is *only* due to these
units and not masked off by something else.
Again, if we're discussing optimization of cars, everything will be
considered. I thought we compare cost of *controllers*.
And, yes, people who pay for features use them. For instance
10 years warranty. (This though rather exception, MES systems
are two years warranty). OR the fact that the motor is sealed
and practically indestructible. You will never overheat it.
That's very nice.
"Nice" isn't enough. Please assign a dollar sign to it.
Or that there are no exposed high voltage connections.
I don't hear, how much does this basic safety feature worth to you?
Or, you can listen to the radio while driving because of
EMI is taken care of.
True, I leave those two up to the flexibility of the installer.
Sometimes they do better than other times.
This is not the question. The question (again for comparison sake)
how much money would *you* charge if you'd need to take care of it.
I can't change the fact that it is already taken care of (and charged
for) in AC inverters. If you don't have something (and so don't charge
for it), it's no longer a fair comparison.
u
Or, you're 100% assured it will not fail full on.
I think you're pushing it on this. A pedal can still get stuck full on
in either system.
C'mon, you know better. I'm talking about consequences of the
power silicon in the controller power stage to fail full on.
Eternal mechanical throttle being "stuck" is not in the picture,
if identical part is used, the chances are the same and have
nothing to do with DC vs AC being discussed.
To be fair, there is no extra money sent for AC inverters to make
them "power silicon fail safe" - this is inherent property of
the principle of operation. For comparison stake you must provide
the same "security level" - this is what people pays premium for.
Or record any of 512 running parameters (any 16 at the time
I believe) as you drive to plot and inspect them later,
Yup, much better, mine only does ten at a time, and I don't provide the
plotting software.
Or...
Who cares, right Otmar? The only fun is shredded rubber!
You seem to have this strange image of me. I think you might be
confusing me with Mad Man Rudman, or maybe Wayland who I think just went
through another set of tires.
The image comes from your consistent reminding that the power is
paramount of the drive property.
As a matter of fact, I've had the same
tires on my car for five years now. They still have legal tread.
I do too. I think, since 1998. Time to change - I get 240Wh/mile
because they are wrong type anyway.
Yes, I enable the worlds most powerful controllers for electric cars
because a number of racers pestered me so much I couldn't say no. But
your image of me seems to be disregarding my work of the last several
years where I've done nothing but try to provide a reasonable cost drive
controller for normal cars.
Sorry if this is your impression, it is wrong one.
Can I help it if many of my customers like
shredding rubber? No. Still my smallest controller is about 80% of my
volume. I think it's just that the many people who use my controllers on
fun normal (and low power) EV's don't post to this list about it as
much. So maybe you don't see that side of my business.
Otmar, there is one fundamental difference between us:
I don't design controllers. (I don't know how, don't want to know
how and as hardware designer, my interest is elsewhere).
As far as drive systems, I sell someone else's product, and can
critique and complain about it if I see something is wrong with it,
and can refuse to buy it from a manufacturer at all. I can
choose other supplier. And I can afford to keep non-popular
inverters in stock - if no sustomer, I just return it to
a manufacturer.
You can't do this, you're in business to make money by making
your own product. So you must watch far more carefully what
exactly 80% of your customers want.
The only reason I have what I have is because every second email I get
is question asking to help to choose, why do I want AC?
I get a lot of those questions too. More like "should I go AC or DC?" I
think it might have been one of those that I told to check out the
discussions on this list that may have started this whole exchange.
(Sorry about that everyone. Hopefully we'll get the archives or a FAQ
working soon.) Of course, I was hoping he would be hearing from people
other than Victor and I since I know we are both busy, and others seem
to present the issues with less bias.
Frankly, while help to decide is needed, it's like asking what kind of
car do you recommend me to drive? There is no answer to that.
Better for you then, less competition from me :-)
No please! Take my customers! My backorder list is too long as it is. :-)
I sure will. Don't worry though, you'll still have plenty left :-)
And now, for those who have sat through this long exchange, I return you
to your regularly scheduled EV discussion list...
Good idea.
Victor
--- End Message ---
--- Begin Message ---
Hi All,
We had a great time at the 5th EVer Chapter Conference in Joliet, Ill
last weekend. Despite the weather trying to play havoc with our
spirits, we prevailed. You can see what I mean at
http://www.rtpnet.org/~teaa/5thEVerThumbs.htm where in the Pep Boys
parking lot the White Zombie went fender to fender with Matt Graham's
Nissan 240 SX in a classic burnout (mpg) .
We want to thank the Fox Valley folks for all their efforts from a tour
of the Warfield motor plant to some great restaurants, to just plain
hosting this large event on a volunteer basis. Hats off to Todd Dore
who chaired this event to Jerry Asher, Ted Lowe and the Fox Valley crew
who did a lot of the behind the scenes phone calls, leg work,
coordinating, web mastering, etc. to speakers such as Ted Lowe, Ron
Freund, John Wayland, Terry Wilson who talked shop to Sherry Boschert
who presented some highlights of her soon to be published book: "Plug In
Hybrids"; Fred Blood, Austin Energy Sustainability Officer, who talked
about the Plug In Partnership; Tom Dowling who talked about a Route 66
string of chargers project from LA to Chicago; and Dave Goldstein who
had a spirited discussion with Sherry at lunch on whether batteries were
ready for EV commercialization.
I know that I'm forgetting a few other names and their contributions.
You know who you are, you know what you did, and you are much
appreciated for doing so. Events like this are a welcomed breath of
fresh air that helps us to get recharged.
Thanks again for a great time!!!
Peter Eckhoff, President
Triangle Electric Auto Association
--- End Message ---
--- Begin Message ---
interesting to note that many ev'ers want regen capability
for the 'braking' effect on the car .. feels good .. of course,
it charges batteries too ..
strange that the silent 'gliding' without any acceleration/deceleration
cannot be an accepted feeling .. habbits, "normal" and other kind
of natural human 'feelings' seem to be the reason
..peekay
(pulling or reverse-pulling seems ok :-) .. freely cruising doesn't ??)
Send instant messages to your online friends http://uk.messenger.yahoo.com
--- End Message ---
--- Begin Message ---
You are assuming that people do not use gliding because they are asking
about a technical feature of regen. At least for me, and a number of others
I know, this is not true. Since gliding comes for free on all Evs, I doubt
many people post notes asking about it.
Since I live and drive in a city, I often have to stop (red lights,
crosswalks, stop lights). Sometimes gliding is **not** suitable for these
situations as I would be holding up traffic going well below the speed
limit. In these situations, I use regen as my brakes.
Regen, is also nicely used on descents. Once again, gliding does not always
work here as I would be grossly exceeding the speed limit or running into
the backs of other vehicles.
Rather than assuming it may be better to pose a question: how many people
use gliding as a technique to improve range? What kind of driving
techniques do people use to increase range? Etc.
Don
Don Cameron, Victoria, BC, Canada
see the New Beetle EV project www.cameronsoftware.com/ev
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of peekay
Sent: May 21, 2006 2:44 AM
To: ev@listproc.sjsu.edu
Subject: Re: Regen - as a 'brake'
interesting to note that many ev'ers want regen capability for the 'braking'
effect on the car .. feels good .. of course, it charges batteries too ..
strange that the silent 'gliding' without any acceleration/deceleration
cannot be an accepted feeling .. habbits, "normal" and other kind of natural
human 'feelings' seem to be the reason
..peekay
(pulling or reverse-pulling seems ok :-) .. freely cruising doesn't ??)
Send instant messages to your online friends http://uk.messenger.yahoo.com
--- End Message ---
--- Begin Message ---
Dave Roekle wrote:
Does anyone know if Valence Technologies is delivering their 27-12XP
Rechargeable Lithium-Ion Batteries?
I was quoted a lead-time of 60 days.
What is the cost per battery?
$1900 each, in small quantities. For my lot of 50, only $1760 each.
That's FOB China. This is a quote from last week. The price is pretty
much the same that others were quoted a year ago (In one year, the price
has not moved).
Has anyone tried them yet?
Not me.
Pros / Cons?
Only one con, from my perspective, and I just quoted it.
I currently have 50 Deka gels, Group 31 (8G31DT), which I'd hoped to
retire and replace with the Group 27 version of the Valence lithiums.
Almost half the weight, and more than double the usable capacity
(keeping the gels above 50% DOD, while leaning on the U27's for 80%).
But I decided I'm not going to mortgage my house.
With new gels costing $150 each, FOB nearby, I can replace my pack 10
times before spending as much as the single pack of U27's.
Regards,
Jim
Dave Roekle
951-278-2370
951-278-2886 Fax
AIM: daveroekle
Yahoo: daveroekle
--- End Message ---
--- Begin Message ---
Ralph,
Thanks for the feedback.
Mark Grasser
----- Original Message -----
From: "Ralph Merwin" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Saturday, May 20, 2006 9:09 PM
Subject: Re: G'bye Porsche...
Mark Grasser writes:
Still sounds like something is not right. Who's regs are these? There
should
be current limiting and temp limiting on these, no?
Mark,
These were ancient Mk1 Rudman regulators. As I said, they were not
drawing
too much current, so current limiting would not help. The problem was
that
a raindrop got onto the board and caused a fault in the circuit
controlling
the FET that was driving the load resistor, causing the load resistor to
get
very hot. Temp limiting on the load resistor would've helped (if it could
turn the FET off). Enclosing the regulators in boxes would've helped too.
The current Mk2B regulators have many more features and may not be prone
to
this problem. At least the Mk2B's in my car will never get rain on them
as
they are inside the enclosed battery boxes.
Ralph
--- End Message ---
--- Begin Message ---
--- Bob Bath <[EMAIL PROTECTED]> wrote:
> What if you for some reason, needed to replace the
> flywheel? Now you need a new motor too!
I was thinking of welding the flywheel to the taperlock only. Then have it
machined to reduce
weight and rebalance. It wouldn't be welded to the motor. The taperlock, in
theory, should be
removable from the motor shaft. And if the flywheel needed replacing, couldn't
it be cut off the
taperlock and a new flywheel welded on?
Yes/no?
Dave Cover
--- End Message ---
--- Begin Message ---
Ralph Merwin wrote:
> A fuse is a good idea (and the newer Mk2B's have built-in fuses),
> however this failure mode is one that would not cause the fuse to
> blow. The regulator was happily dumping power into the load like
> normal, but the control circuit was stuck on.
This is why I prefer real resistors instead of MOSFETs acting as
resistors. Transistors typically fail shorted. Resistors typically fail
open.
Also, you can get fuse resistors. They are specially designed to
guarantee it will fail open from either overcurrent or overtemperature,
and that it will not burn or start a fire when it fails.
--
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 ---
Hey Dave
This would make for a dificult bearing replacement, just something to think
about.
Jim Husted
Hi-Torque Electric
Dave Cover <[EMAIL PROTECTED]> wrote:
--- Bob Bath wrote:
> What if you for some reason, needed to replace the
> flywheel? Now you need a new motor too!
I was thinking of welding the flywheel to the taperlock only. Then have it
machined to reduce
weight and rebalance. It wouldn't be welded to the motor. The taperlock, in
theory, should be
removable from the motor shaft. And if the flywheel needed replacing, couldn't
it be cut off the
taperlock and a new flywheel welded on?
Yes/no?
Dave Cover
---------------------------------
Love cheap thrills? Enjoy PC-to-Phone calls to 30+ countries for just 2ยข/min
with Yahoo! Messenger with Voice.
--- End Message ---
--- Begin Message ---
Gnat wrote:
> Its refered to as the Magnus effect. You can buy dimpled tape and
> sheets with this on it... About the only effects you could expect
> to see with the dimple tape on a car is having a nifty conversation
> starter and making the guy who sold you the stuff a wee bit richer.
There was an article in the other EAA (Experimental Aircraft
Association) about this. The author wanted an easy way to experiment
with this effect. He hit upon making a propeller with blades of the
shape he wanted to evaluate. Spin it with an electric motor, and measure
rpm (airspeed) vs current (drag). Kind of a free-air version of a wind
tunnel.
In his case, it led to developing an improved wing profile / propeller
with dimples just behind the thickest point in the cross-section.
So... how about mounting a model car on a counterweighted arm. Spin it
with an electric motor. Control the motor voltage to control the
airspeed of the car). Measure the motor current to determine its
aerodynamic drag. You could even include the effect of the road by
putting a stationary ring around the outside, just barely missing the
wheels of the car.
Now you an experiment with various aerodynamic mods with ease. Buy a
model car kit of your favorite car, and try all the mods and testing
with it.
--
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 ---
Lawrence,
I'd like to talk to the fellow that has the Edison Batts. Can you give
me some contact info?
Mike
--- End Message ---
--- Begin Message ---
[EMAIL PROTECTED] wrote:
> in my experience the device data sheets are quite accurate. What
> is often overlooked is what the maximum rating means. That is the
> voltage that should never, ever be exceeded.
I agree! The numbers on the front page of a data sheet, and that are
given in the one-line description in a catalog are the *absolute
maximum* ratings. Your actual application should never come anywhere
near these values if you expect it to last more than a matter of
minutes.
Once you get into the "meat" of the data sheet, it provides a lot more
data on typical and minimum values, derating curves at various
temperatures, etc. The real challenge in designing a reliable product is
to properly interpret this data so you always stay within these
guidelines, no matter what sort of abuse the customer may devise.
> Motor controllers are basically a power supply that use the motor
> as the inductor.
And the battery as the capacitor. Both are rather poor examples of a
"good" inductor or capacitor. The result is rather poor control of the
amount of noise and ringing you get.
> So, a switcher using devices with an absolute max rating of 300
> volts should not be operated over 150 volts of supply.
Novice controller designers, and many inexpensive EV controllers use
smaller safety factors than this. It is common to see 200v rated parts
in a controller rated for 120v or 144v battery packs. Happy, happy, joy,
joy... BANG!
--
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 Dave and all,
I just look at my taperlock adapter, and the problem I would have, is that I
have to install the adapter on the motor first, before I install the
flywheel, otherwise I cannot get to the 6 set screws, where three of them
are for installing the coupler and 3 of them are for removing.
The special design taperlock from Electro Auto have smaller installing
screws where all 6 screws are installing type which would work for
installing the taperlock and flywheel together, but removing this coupler
still takes a heavy duty locking type puller using a air driven impact
wrench.
While you have your taper lock modified to fit your flywheel, have the
machinist make a centering insert that will be place into the transmission
pilot bearing bushing, so the wheel puller center point has something to
push against with damaging the motor shaft.
The wheel puller will have to be the type, that has large sliding bars that
can bridge the diameter of the flywheel at three points and then bolt to the
flywheel at the same place the pressure plate bolts on.
A large wheel splitter may work, as long as you do not damage the motor
housing, which the wheel splitter presses against.
To pull my taper lock that does not have any removable screws with the
flywheel removed, it took a tremendous force with the impact wrench crank
all the way up to 120 psi, which the taper lock finally broke loose with a
load explosion.
Roland
----- Original Message -----
From: "Dave Cover" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, May 21, 2006 8:03 AM
Subject: Re: Taperlock dilemma
> --- Bob Bath <[EMAIL PROTECTED]> wrote:
> > What if you for some reason, needed to replace the
> > flywheel? Now you need a new motor too!
>
> I was thinking of welding the flywheel to the taperlock only. Then have it
> machined to reduce
> weight and rebalance. It wouldn't be welded to the motor. The taperlock,
> in theory, should be
> removable from the motor shaft. And if the flywheel needed replacing,
> couldn't it be cut off the
> taperlock and a new flywheel welded on?
>
> Yes/no?
>
> Dave Cover
>
>
--- End Message ---
