EV Digest 7043
Topics covered in this issue include:
1) Re: Simple Controller
by [EMAIL PROTECTED]
2) VW Super EV Project for Sale
by "Shawn M. Waggoner" <[EMAIL PROTECTED]>
3) Jetta Adapter Plate and Gast Pump on eBay
by "Shawn M. Waggoner" <[EMAIL PROTECTED]>
4) Re: Tell Me Which DC to DC Converter I Should Use
by David Wilker <[EMAIL PROTECTED]>
5) best way to transport a newly purchased EV
by "Michael Mohlere" <[EMAIL PROTECTED]>
6) Re: Simple Controller
by Dan Frederiksen <[EMAIL PROTECTED]>
7) Re: best way to transport a newly purchased EV
by BrownGassyTurd <[EMAIL PROTECTED]>
8) Re: Tell Me Which DC to DC Converter I Should Use
by Ralph Merwin <[EMAIL PROTECTED]>
9) "Fair Radio Charger" Wiring Diagram
by Mike Chancey <[EMAIL PROTECTED]>
10) Re: Simple Controller
by Jeff Shanab <[EMAIL PROTECTED]>
11) Re: Simple Controller
by Thomas Ward <[EMAIL PROTECTED]>
12) Re: Simple Controller
by Ian Hooper <[EMAIL PROTECTED]>
13) Re: Simple Controller
by Dan Frederiksen <[EMAIL PROTECTED]>
14) Re: Simple Controller
by "Evan Tuer" <[EMAIL PROTECTED]>
15) Re: Simple Controller
by Dan Frederiksen <[EMAIL PROTECTED]>
16) Re: Simple Controller
by "Peter VanDerWal" <[EMAIL PROTECTED]>
17) Re: Simple Controller
by Chip Gribben <[EMAIL PROTECTED]>
18) Re: Simple Controller
by Dan Frederiksen <[EMAIL PROTECTED]>
19) Re: Simple Controller
by "Roland Wiench" <[EMAIL PROTECTED]>
20) Re: Tell Me Which DC to DC Converter I Should Use
by "Richard Acuti" <[EMAIL PROTECTED]>
21) Re: best way to transport a newly purchased EV
by "Timothy Balcer" <[EMAIL PROTECTED]>
22) 6v or 12v
by Jack Murray <[EMAIL PROTECTED]>
23) Is THIS the PHEV announcement ?
by Steven Lough <[EMAIL PROTECTED]>
24) Re: Simple Controller
by Thomas Ward <[EMAIL PROTECTED]>
25) Re: Simple Controller
by Thomas Ward <[EMAIL PROTECTED]>
26) Re: Virtual Instrumentation Solution
by Lee Hart <[EMAIL PROTECTED]>
27) Re: Simple Controller
by Lee Hart <[EMAIL PROTECTED]>
28) "Tree House" Controller
by Lee Hart <[EMAIL PROTECTED]>
29)
by "Thomas Brannan" <[EMAIL PROTECTED]>
30) Re:
by "Thomas Brannan" <[EMAIL PROTECTED]>
31) Re: "Tree House" Controller
by "(-Phil-)" <[EMAIL PROTECTED]>
--- Begin Message ---
Thanks everyone,
This you have put my mind to rest. I had to clear up my notion of a
barebones simplistic controller once and for all. I don't like to waste my
time since I can spend it either working to buy a Curtis or doing one of
my many other interests. Madman, I don't mean to be touchy or thin skinned
but I hope you don't include me in that bunch of "do nothing talkers". I
am half way done with my conversion and have many other hobbies that I DO.
watercooled my computer, homemade foundry, restored and painted classic
cars etc. I try to keep my questons to the point and usually only ask when
the list is the only place to get a specific answer. Thanks again for
everyones input.
Paul
--- End Message ---
--- Begin Message ---
Hi Everyone,
Well I'm selling a VW Beetle project that I don't have time for right
and it's looking like I won't have time for anytime soon. So, I'm
selling it!
I have the car and parts up on eBay (item 230154106495) with LOTS of
pictures.
Here are the basics:
1973 VW Super Beetle
8" Advanced DC 4001 Motor
New Adapter Plate, Pressure Plate, Clutch, Gland Nut
Motor Mount Bracket
Curtis 1231C 120VDC 550A Controller
PB6 Throttle
120VDC Charger 15A
New Tires and Front Disc Brakes
New Shifter
Dash Cover
I am also including a brand new tow bar that I bought for it and the
domain name for the project site I created (www.evbug.net)
Please let me know off-list if anyone has any questions.
Thanks,
Shawn Waggoner
Florida EAA
--- End Message ---
--- Begin Message ---
Clearing some EV parts from the shop if anyone is interested:
VW Jetta Adapter plate from a 1996 Jetta for a 8" Motor:
eBay item 230154101994
Gast Model MOA-V111-JH 12VDC Vacuum Pump, Switch and Gauge
eBay item 230154103734
Thanks!
Shawn Waggoner
Florida EAA
--- End Message ---
--- Begin Message ---
Have you considered running the original alternator off the shaft?
David C. Wilker Jr.
USAF (RET)
---- Lee Hart <[EMAIL PROTECTED]> wrote:
From: Joseph Lado
> I have had it. I have been stranded by my auxilary battery. I don't
> have a DC to DC converter... If I have to drive at night in rain I can
> only go about 10 miles before the battery craps out. I need a DC to DC
> converter. I tried to use the IOTA 35. That didn't work. My pack is
> 108 volt pack and somehow that isn't enough for the IOTA35.
The Iota is really a 120vac input supply. It rectifies this to produce 160
volts DC. Your 108 volt pack is much less than this -- too low for the Iota to
work acceptably.
> Just tell me what I should buy that works with my 18 Trojan 6 volt
> batteries? What is the best choice?
"Best" is a judgement call. But if it were me, I'd look for a pair of 48v
input, 13.5v output DC/DC converters. These are very common, as 48vdc is widely
used in industry and telephone systems. Use two of them, each powered by half
your pack (108v/2 = 54v; these converters actually work from 36-72vdc). Two
converters also provides redundancy; if one fails, the other still provides 12v
power.
--
"Excellence does not require perfection." -- Henry James
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart-at-earthlink.net
--- End Message ---
--- Begin Message ---
If anyone can provide a referral to a good, reliable shipper for
transporting my newly purchase EV from
Roeland Park, KS to Huntsville, AL, I'm all ears...have a similar post on
the MAEEA (sp?) list.
Thx, Mike
_________________________________________________________________
http://newlivehotmail.com
--- End Message ---
--- Begin Message ---
Rich, how many horses is 300V and 300A?
Rich Rudman wrote:
Oh.. not much as it seams here...
Please keep us informed as the amount of your cash that turns into spendy
Smoke...
This aughta be good...
I'll bring Hershies and Grammcrakers to the IGBT roasting party.
300 amps and 300 volts... Not even Curtis amps.... Hoo ho ho... Good one
there...
I can run that fast....and I am a fat old man....This might be good for a
750 lbs NEV....
You need more amps.
Madman
----- Original Message -----
From: "Dan Frederiksen" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, July 19, 2007 5:04 PM
Subject: Re: Simple Controller
hehe that's rich. I know what an IGBT is. I plan to use them. you didn't.
and from what I understand they can be used rather simply. a pwm, an
IGBT driver and the IGBTs (caps etc). and they are not terribly
expensive either.
Otmar said the IGBTs in the zilla 1K cost him 165$ and 1000amps is way
too much for a normal car. As I understand it, higher than the typical
100-150v is more important than amps so the car can do freeway speeds
too instead of just initial strong acceleration.
the trick is to connect it right and watch for high current. but with
the right knowledge it should be a simple circuit
and the parts relatively cheap.
others have succesfully built controllers themselves.
a shame that noone has yet made a good simple robust design that
everyone can make but perhaps that will happen.
something like a 300V 300A spec would be nice I believe. but hey, what
do I know :)
Dan
--- End Message ---
--- Begin Message ---
I used and do not hesitate in recommending:
www.nationalautoshipping.com
toll free phone 1-877-393-3232
toll free fax 1-888-415-1113
The driver brought my car from Maryland to So.California and gave me
status reports and cell phone pictures from the trip.
Oh yeah they pretty much had the cheapest quote too. :)
Manny
On 7/19/07, Michael Mohlere <[EMAIL PROTECTED]> wrote:
If anyone can provide a referral to a good, reliable shipper for
transporting my newly purchase EV from
Roeland Park, KS to Huntsville, AL, I'm all ears...have a similar post on
the MAEEA (sp?) list.
Thx, Mike
_________________________________________________________________
http://newlivehotmail.com
--
http://www.austinev.org/evalbum/1117
http://EVorBust.blogspot.com
--- End Message ---
--- Begin Message ---
Joseph,
The Sevcon sold by Electro Automotive might work for you:
http://www.electroauto.com/catalog/dc-dc.shtml
Ralph
Joseph Lado writes:
>
> I have had it. My pack in my Destiny2000 solar paneled conversion of a
> Pontiac Fiero gets me 50 miles on a charge. I have never been stranded by my
> pack anywhere. I have been stranded by my auxiliary battery. I don't have a
> DC to DC converter and even though my Trojan maintenance free battery is
> great, but, it simply is very limited. If I have to drive at night in rain I
> can only go about 10 miles before the battery craps out. I need a DC to DC
> converter. I tried to use the IOTA 35. That didn't work. My pack is 108 volt
> pack and somehow that isn't enough for the IOTA35. Just tell me what I should
> buy that works with my 18 Trojan 6 volt batteries? What is the best choice?
> Please. Joe Lado
>
--- End Message ---
--- Begin Message ---
Hi folks,
I know this is a really long shot, but would anyone happen to have
the wiring diagram for those military surplus power supplies we
referred to as Fair Radio chargers? I bought the manual when I
bought my FR, but I misplaced it years ago.
Thanks,
Mike Chancey,
'88 Civic EV
Kansas City, Missouri
EV Photo Album at: http://evalbum.com
My Electric Car at: http://www.geocities.com/electric_honda
Mid-America EAA chapter at: http://maeaa.org
Join the EV List at: http://www.madkatz.com/ev/evlist.html
In medio stat virtus - Virtue is in the moderate, not the extreme
position. (Horace)
--- End Message ---
--- Begin Message ---
I am gonna have to agree.
When I accelerate gently from a stoplight, my 4000lb EV (including
this fat old man driving it) I can do it with 200 battery amps if people
aren't behind me
This is because at launch I may be only at 10% duty createing an average
voltage of around 60 at the motor. In these first few mph only 50 amps
is drawn, but the duty cycle quickly climbs and so does the voltage at
the motor. It climbs rapidly to 200A. From there, I can choose to paltry
accelerate or keep pushing to 400ish battery amps.
The 300V 200A becomes 60V 1000A at the motor. If you were limited to
300A in the motor loop, It would end up takeing 1-2 min to get to 45-50
on level grade.
I think 1000amps on a single 9 is just adequete.
Loose weight or increase amps.
--- End Message ---
--- Begin Message ---
I have always been curious about the need for high amps.
The documentation for Citroen Berlingos states that peak current is 200
amps, and I think this is probably correct because the IGBT is only
rated 300 amps. There is more than enough acceleration. Vehicle weighs
2 tonnes.
The motor is a sepex, is that why Citroen can get away with this low
amperage and still have acceleration at low speed?
Perhaps this a way forward for budget controllers, 100 amp continuous +
sepex motor?
Rich Rudman wrote:
300 amps and 300 volts... Not even Curtis amps.... Hoo ho ho... Good one
there...
--- End Message ---
--- Begin Message ---
High amps are not necessarily required, it just happens that most
series DC motors used in EVs have very low impedance, which results
in high current flow at a given voltage.
Amps by themself aren't an indication of a vehicle's power. Power is
voltage x current, so if a motor was carrying 300 amps at 300 volts,
that's 90kW of electrical power (which should be plenty for driving a
car)! But in most EVs, you'll have a much lower voltage pack and a
low impedance motor, so need higher current for a given power.
Getting power from higher voltage & lower current has some
advantages, in particular power lost to heat in a circuit equals the
*square* of the current times resistance. (But there are
disadvantages of course, like higher semiconductor losses etc.)
On 20/07/2007, at 2:10 PM, Thomas Ward wrote:
I have always been curious about the need for high amps.
The documentation for Citroen Berlingos states that peak current is
200 amps, and I think this is probably correct because the IGBT is
only rated 300 amps. There is more than enough acceleration.
Vehicle weighs 2 tonnes.
The motor is a sepex, is that why Citroen can get away with this
low amperage and still have acceleration at low speed?
Perhaps this a way forward for budget controllers, 100 amp
continuous + sepex motor?
Rich Rudman wrote:
300 amps and 300 volts... Not even Curtis amps.... Hoo ho ho...
Good one
there...
--- End Message ---
--- Begin Message ---
what car and what gear is that?
Jeff Shanab wrote:
I am gonna have to agree.
When I accelerate gently from a stoplight, my 4000lb EV (including
this fat old man driving it) I can do it with 200 battery amps if people
aren't behind me
This is because at launch I may be only at 10% duty createing an average
voltage of around 60 at the motor. In these first few mph only 50 amps
is drawn, but the duty cycle quickly climbs and so does the voltage at
the motor. It climbs rapidly to 200A. From there, I can choose to paltry
accelerate or keep pushing to 400ish battery amps.
The 300V 200A becomes 60V 1000A at the motor. If you were limited to
300A in the motor loop, It would end up takeing 1-2 min to get to 45-50
on level grade.
I think 1000amps on a single 9 is just adequete.
Loose weight or increase amps.
--- End Message ---
--- Begin Message ---
On 7/20/07, Thomas Ward <[EMAIL PROTECTED]> wrote:
I have always been curious about the need for high amps.
The documentation for Citroen Berlingos states that peak current is 200
amps, and I think this is probably correct because the IGBT is only
rated 300 amps. There is more than enough acceleration. Vehicle weighs
2 tonnes.
Strange, mine weighs 1.45 tonnes. And the IGBT is a 400A part.
With maximum battery power of about 28kW, the acceleration is "more
than enough" up to about 25MPH, above which it is best described as
"leisurely". This is fair enough since it's a delivery van and
intended for city driving with 30 or 40mph speed limits.
Anyway, this is little to do with the current rating of the
controller. You could achieve the same power with a 500A controller,
and a 72V pack.
--- End Message ---
--- Begin Message ---
Do you have a picture of the electronics? (model/make of the IGBT)
is the berlingo a DC drive?
what system voltage?
Dan
Evan Tuer wrote:
Strange, mine weighs 1.45 tonnes. And the IGBT is a 400A part.
--- End Message ---
--- Begin Message ---
Something doesn't add up. My truck weighs 1.5 tons. My controller does
550 amps, motor loop, and 350 amps battery loop. Acceleration is
lethargic, 0-60mph in about 1.5 minutes.
> I have always been curious about the need for high amps.
>
> The documentation for Citroen Berlingos states that peak current is 200
> amps, and I think this is probably correct because the IGBT is only
> rated 300 amps. There is more than enough acceleration. Vehicle weighs
> 2 tonnes.
>
> The motor is a sepex, is that why Citroen can get away with this low
> amperage and still have acceleration at low speed?
>
> Perhaps this a way forward for budget controllers, 100 amp continuous +
> sepex motor?
>
>
> Rich Rudman wrote:
>
>> 300 amps and 300 volts... Not even Curtis amps.... Hoo ho ho... Good one
>> there...
>>
>
>
--
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 ---
Rod's right. There is a slew of Chinese controllers out there, but
only for the scooter market. Mostly 24 volts. Above 48 volts, I
haven't seen any.
For example, check this site out and scroll to the bottom half of the
page.
http://www.scootercontroller.com
You'll see rows and rows of 24 volt scooter controllers. At the most
they can handle 30 to 40 amps. Easy and cheap to make. Above 60 amps
with motors in the 1000 to 2000 watt range your getting into more
complex circuits that the full size 48 volt scooters use and that's
where you start to see the Alltrax and Curtis type controllers. If
the Chinese saw a market for larger ones then 48 volt 60 amp
controllers they would be doing it.
And thank goodness they don't. I have boxes of melted and burnt out
24 volt Chinese controllers. I keep them to salvage the wires and
connectors.
Chip Gribben
www.electroscooterworks.com
On Jul 19, 2007, at 11:06 PM, Electric Vehicle Discussion List wrote:
From: Rod Hower <[EMAIL PROTECTED]>
Date: July 19, 2007 9:43:12 PM EDT
To: ev@listproc.sjsu.edu
Subject: Re: Simple Controller
the trick is to connect it right and watch for high
current. but with
the right knowledge it should be a simple circuit
and the parts relatively cheap.
Yep, it must be pretty simple and cheap, that's why we
see a flood of EV controls coming from China (since
it's so easy they should be cranking them out by
now!).
Two problems, it's not cheap and easy and there is not
a big enough market to create these controls. If
there's money to be made I'm sure the Chinese would be
cranking these out in high volume. That's the
problem, there is not a big market for these controls
to bring down the price in volume. When you produce
controls in lower volume you have to spread out the
engineering and manufacturing cost to cover your
expenses. Knowing what it takes to produce a control,
I realize that people like Rich Rudman and Otmar
aren't making big bucks, just producing a product in
low volume to serve the EV market. When you actually
design and manufacture a control like this you'll know
what I mean concerning low volume cost. A good
comparison would be the PC. You can buy a nice high
performance desktop for $300 to $400 bucks new.
Imagine what it would cost if you were producing 1000
PC's, contracting out all of the individual circuit
boards and also hand building many of the parts
manually (not automated assembly, which you CANT do
with a Zilla control).
I guess I'm just rambling, but I know the time
involved in producing low volume controls (I have put
together many low volume prototypes of my 2HP BLDC
control for the transportation market which is just
starting to order higher volumes of controls, the
first 100 were very expensive and the next 1000 will
still be very costly do to the low volume
manufacturing). Once they get up to the 10k to 20k
volume they will be quite a bit cheaper, but will
still cost quite a bit because they are not being
produced in the 1 million quantity (probably 1/3 the
cost!!).
So, my advice is to put in the sweat equity and see
what it actually costs to produce something at the
cost you envision.
Good luck!
Rod
--- Dan Frederiksen <[EMAIL PROTECTED]> wrote:
hehe that's rich. I know what an IGBT is. I plan to
use them. you didn't.
and from what I understand they can be used rather
simply. a pwm, an
IGBT driver and the IGBTs (caps etc). and they are
not terribly
expensive either.
Otmar said the IGBTs in the zilla 1K cost him 165$
and 1000amps is way
too much for a normal car. As I understand it,
higher than the typical
100-150v is more important than amps so the car can
do freeway speeds
too instead of just initial strong acceleration.
the trick is to connect it right and watch for high
current. but with
the right knowledge it should be a simple circuit
and the parts relatively cheap.
others have succesfully built controllers
themselves.
a shame that noone has yet made a good simple robust
design that
everyone can make but perhaps that will happen.
something like a 300V 300A spec would be nice I
believe. but hey, what
do I know :)
Dan
--- End Message ---
--- Begin Message ---
what system voltage?
I'm guessing low. starts quick enough but gets weak at higher speed
Peter VanDerWal wrote:
Something doesn't add up. My truck weighs 1.5 tons. My controller does
550 amps, motor loop, and 350 amps battery loop. Acceleration is
lethargic, 0-60mph in about 1.5 minutes.
I have always been curious about the need for high amps.
The documentation for Citroen Berlingos states that peak current is 200
amps, and I think this is probably correct because the IGBT is only
rated 300 amps. There is more than enough acceleration. Vehicle weighs
2 tonnes.
The motor is a sepex, is that why Citroen can get away with this low
amperage and still have acceleration at low speed?
Perhaps this a way forward for budget controllers, 100 amp continuous +
sepex motor?
Rich Rudman wrote:
300 amps and 300 volts... Not even Curtis amps.... Hoo ho ho... Good one
there...
--- End Message ---
--- Begin Message ---
Hello Jeff,
What is the overall gear ratio's you have to pull that much motor amperes?
I am running about a 20:1 in 1st gear and about 14:1 and 2nd gear.
I can run from 0 to 25 mph which is about 6000 rpm in 1st gear in about 10
seconds with a peak motor ampere of 300 amps. When I shift to 2nd gear at
25 mph it will peak to about 500 amps briefly and it will come back to 200
amps when I reach 30 mph in the next 5 seconds.
My battery ampere ranges from 100 amps at acceleration and comes back to 40
amps at cruse.
This is about a normal acceleration for me. I am a afraid to push it to the
floor like a Mad Man, because the motor coupler may shatter like it did when
I foot slip off the brake peddle onto the accelerator and it hop like a
grasshopper.
Roland
Roland
----- Original Message -----
From: "Jeff Shanab" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List" <ev@listproc.sjsu.edu>
Sent: Thursday, July 19, 2007 11:44 PM
Subject: Re: Simple Controller
> I am gonna have to agree.
>
> When I accelerate gently from a stoplight, my 4000lb EV (including
> this fat old man driving it) I can do it with 200 battery amps if people
> aren't behind me
>
> This is because at launch I may be only at 10% duty createing an average
> voltage of around 60 at the motor. In these first few mph only 50 amps
> is drawn, but the duty cycle quickly climbs and so does the voltage at
> the motor. It climbs rapidly to 200A. From there, I can choose to paltry
> accelerate or keep pushing to 400ish battery amps.
>
> The 300V 200A becomes 60V 1000A at the motor. If you were limited to
> 300A in the motor loop, It would end up takeing 1-2 min to get to 45-50
> on level grade.
>
> I think 1000amps on a single 9 is just adequete.
>
> Loose weight or increase amps.
>
>
--- End Message ---
--- Begin Message ---
Hmmm....I have the Sevcon 128/12 model yet when I went to their website, all
I could find were much lower input voltage models (72v). Did they quit
making the 128v models? That would be very uncool. I love mine. I was going
to recommend it until I couldn't find it.
So: If mine died, what is available in that input/output voltage and power
range? Just give me some brand names and I'll look them up.
Rich A.
Message-ID:
<[EMAIL PROTECTED]>
Date: Thu, 19 Jul 2007 20:06:05 -0700 (GMT-07:00)
From: Lee Hart <[EMAIL PROTECTED]>
To: ev@listproc.sjsu.edu
Subject: Re: Tell Me Which DC to DC Converter I Should Use
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
From: Joseph Lado
I have had it. I have been stranded by my auxilary battery. I don't
have a DC to DC converter... If I have to drive at night in rain I can
only go about 10 miles before the battery craps out. I need a DC to DC
converter. I tried to use the IOTA 35. That didn't work. My pack is
108 volt pack and somehow that isn't enough for the IOTA35.
The Iota is really a 120vac input supply. It rectifies this to produce 160
volts
DC. Your 108 volt pack is much less than this -- too low for the Iota to
work
acceptably.
Just tell me what I should buy that works with my 18 Trojan 6 volt
batteries? What is the best choice?
"Best" is a judgement call. But if it were me, I'd look for a pair of 48v
input,
13.5v output DC/DC converters. These are very common, as 48vdc is widely
used in
industry and telephone systems. Use two of them, each powered by half your
pack
(108v/2 = 54v; these converters actually work from 36-72vdc). Two converters
also provides redundancy; if one fails, the other still provides 12v power.
--
"Excellence does not require perfection." -- Henry James
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart-at-earthlink.net
_________________________________________________________________
http://im.live.com/messenger/im/home/?source=hmtextlinkjuly07
--- End Message ---
--- Begin Message ---
Or... you can build a pusher trailer and bring it with :-)
--T
--- End Message ---
--- Begin Message ---
I'll be moving my Optima batteries to my sailboat, so I'm going to get
some new batteries for the Fiero.
I'm leaning towards getting the Trojan 24TM 12v batteries, and go with
10-20 of them. It seems to me the higher voltage is going to reduce
current draw and be better for range via pukert. How many volts can
an ADC 8" motor be OK with? Is 240v too much?
Jack
--- End Message ---
--- Begin Message ---
Is THIS the PHEV announcement Every One has been Waiting For ?
Dateline TOYOTA Japan 20 - July
Off the Google - Alert - Electric Car News Feed...
( http://www.asahi.com/english/Herald-asahi/TKY200707200126.html )
--
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 ---
Your motor is series?
I think this may be because at about 7mph the voltage in the armature of
this sepex motor is already about 90volts 90V x 200A is a > 15KW.
By about 15mph the voltage is about 140-180V depending on SOC.
The voltage in a series motor at 7-15mph is going to be about 10-20V ?
so it needs higher amps.
I guess acceleration is relative but 0-60 in the van seems OK to me
probably about 30 seconds, its fairly aerodynamic, petrol version does
about 45mpg.
Peter VanDerWal wrote:
Something doesn't add up. My truck weighs 1.5 tons. My controller does
550 amps, motor loop, and 350 amps battery loop. Acceleration is
lethargic, 0-60mph in about 1.5 minutes.
I have always been curious about the need for high amps.
The documentation for Citroen Berlingos states that peak current is 200
amps, and I think this is probably correct because the IGBT is only
rated 300 amps. There is more than enough acceleration. Vehicle weighs
2 tonnes.
The motor is a sepex, is that why Citroen can get away with this low
amperage and still have acceleration at low speed?
Perhaps this a way forward for budget controllers, 100 amp continuous +
sepex motor?
Rich Rudman wrote:
300 amps and 300 volts... Not even Curtis amps.... Hoo ho ho... Good one
there...
--- End Message ---
--- Begin Message ---
Hello Evan,
> Strange, mine weighs 1.45 tonnes.
sorry should have said 1.5 tonnes + .5 tonne payload
>And the IGBT is a 400A part.
Are you sure?
The IGBT in my van is Toshiba MG300J2YS50 , when I read the data sheet
of this part I understand that max continuous current is 300A at only 25
degrees C.
The fuses are rated 220A for 5 minutes. And the manual says the
controller is limited to 200A
When you say 400A do you mean continuous or peak?
I wonder if Citroen changed the spec at some point
What year is yours?
mine is 2000.
Evan Tuer wrote:
On 7/20/07, Thomas Ward <[EMAIL PROTECTED]> wrote:
I have always been curious about the need for high amps.
The documentation for Citroen Berlingos states that peak current is 200
amps, and I think this is probably correct because the IGBT is only
rated 300 amps. There is more than enough acceleration. Vehicle weighs
2 tonnes.
With maximum battery power of about 28kW, the acceleration is "more
than enough" up to about 25MPH, above which it is best described as
"leisurely". This is fair enough since it's a delivery van and
intended for city driving with 30 or 40mph speed limits.
Anyway, this is little to do with the current rating of the
controller. You could achieve the same power with a 500A controller,
and a 72V pack.
--- End Message ---
--- Begin Message ---
Timothy Balcer wrote:
I was wondering... if you shielded and twisted all of your cable runs,
and made your battery boxes Faraday tight, would that eliminate some
of the noise trouble? I realize you get EMF from the motor and
controller.. could that be limited as well with a faraday shield
surrounding, or perhaps at least shielding in the right directions,
the engine compartment?
Sure; you can shield it as tightly as desired, to the point where the
noise is undetectable without delicate instruments. However, that costs
money.
People are of course reluctant to spend money on things unless they are
sure it's necessary.
--
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 ---
[EMAIL PROTECTED] wrote:
Why can't I use a PWM signal, amplified through a motor driver to
switch a high power SCR? Is this how the old SCR controllers work so
can I just use an SCR big enough for the voltage and current I want
to handle? Just looking for the simplest solid state possible.
There's a lot of controller info in the EV list archives. There are also
dozens (if not hundreds) of designs in books, manufacturer's application
notes, and on the web. A little research will reveal a gold mine of data.
An SCR PWM controller is indeed pretty simple; very few parts. It's just
that some of these parts are pretty big. SCRs are easy to turn on, but
hard to turn off. There is usually a big inductor, capacitor, and 2 or 3
extra SCRs or diodes to turn the main SCR off.
--
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 ---
[EMAIL PROTECTED] wrote:
Yeah, I thought IGBT's might be the one thats I needed. But how do
forklift scr's work? All I want to do is turn voltage on and off really
fast. I guess there really is just no way to do it without high tech
electronics.
If you lower your expectations enough, then a simple PWM controller is
possible. The main tradeoffs are:
- It will be acoustically noisy (you can hear it operating),
- It will be slightly less efficient (a few percent).
- Power will be modest, like a Curtis controller.
- It won't be "idiot proof", i.e. it will have little or no
protection from overtemperature, undervoltage, overcurrent, etc.
- It will have somewhat "lumpy" operation; things like a small
lurch when starting out, or a throttle response that doesn't
match a normal ICE's, etc.
- There will be "surprise" failure modes, due to design or
assembly errors (stuff you don't know when you build it).
SCRs are cheap, rugged, and easy to turn on (even easier than MOSFETs or
IGBTs). The tradeoff is that they are hard to turn off. The classic
method is to have a big inductor, a big capacitor, and 1 or 2 extra big
SCRs or diodes. The circuits are very basic and well documented; it's
just that these are big parts!
could not the IGBTt just be in line with the motor and batteries
switched on and off by a gate current? I'm well aware of the problems
involved with real controllers, it just seems like a solid state
on/off switch could be rigged up without any bells or whistles.
If you're using the IGBT as a solid-state contactor, then there are no
switching loss concerns. You just have to deal with the heat produced by
its 3v drop at full current.
You will always need a freewheel diode. It is easiest to get an IGBT
module that has one built-in, as it will naturally have short leads and
be matched to the IGBT's capabilities.
If you want to duty-cycle modulate that IGBT to make a PWM controller,
then it gets interesting. Now you have to deal with switching losses,
which can exceed conduction losses (twice the heat, which means twice
the cooling and/or having to use the parts at half their ratings). And,
you have to make fast, accurate measurements in noisy high-power
switching circuits, for current limit and voltage protection to work.
I think the trouble with simple cheap controllers is the "tree house"
problem. It goes like this:
1. Kids want a tree house. They know they can scrounge up some scrap
lumber, find a can of rusty nails in the garage, steal dad's hammer
and saw, and build it in a day or two!
2. But dad knows it will be a ramshackle structure, badly built,
probably unsafe, and certainly ugly.
What's likely to happen?
A. Kids don't tell dad. They build it themselves. It takes a week
instead of a month, due to all the "surprises" along the way.
They smash thumbs, get splinters, bend nails, need to scrounge
more materials, but manage to cobble something together. It looks
and works terrible; but they learned a lot and love it anyway.
B. Dad gets involved. He says, "We have to do this right". He makes
plans, buys materials, tries to supervise but winds up doing it
himself because the kid's workmanship is so poor. It takes him
all summer to build it. It looks great and is safe; but the kids
rarely use it; they're off on some other hot new interest.
It's hard for experts to remember that beginners have far lower
standards of quality and performance. The expert knows how to do it
"right" -- build something that even he would be proud to use. But it's
very hard for him to build a "tree house controller" that is
disgustingly cheap crude and primitive.
But the beginner, having no experience with real controllers, may be
perfectly happy with a "tree house controller", thrown together out of
cheap surplus parts, that works but has all sorts of problems.
The middle ground is difficult to achieve. It would be like:
C. Dad supervises, but forces himself to keep his hands in his pockets
and his mouth shut most of the time. He shows them how to use a
hammer and saw, but doesn't do the work for them (so they learn how
to do it themselves). He shows them how to make strong joints so it
won't fall apart, but lets them do it their way (so they learn the
consequences of not doing it right). Dad knows that learning is the
real goal; not the end product itself.
The end result is a tree house that still looks pretty crude; but it is
a heck of a lot stronger and safer that it would have been without adult
supervision. And the kids still love it, because they made it themselves!
--
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 ---
help set
--- End Message ---
--- Begin Message ---
OOPS! Well, color me embarassed!!
Sorry, guys.
Regards,
Tom
On 7/20/07, Thomas Brannan <[EMAIL PROTECTED]> wrote:
help set
--- End Message ---
--- Begin Message ---
Awesome Lee, I love the "Treehouse" analogy. I will dispense this wise
analogy (with credit to you) to many for years to come!
He is absolutely right. I am by no means an "expert" on high-power PWM
controls, but I have a few under my belt, including many which still
operate. But when I look back at my earliest projects, one of which I still
have in my junk collection (but don't use), it makes me laugh at myself.
Sure, it works, but I would have slapped myself if I could go back in time.
I to remember this when I look over someone else's shoulder when they try to
attempt such things. It's best to be the dad who keeps his hands in his
pockets.
There is really no effective way to teach someone with the same educational
value of a whole row of parallel MOSFETs all blown to bits!
When it happened to me the first time, I felt like I was in the middle of
Hiroshima! There was a visible fireball of white plasma and mini-mushroom
cloud of blue smoke. I had a T-bridge (PWM speed control with Regen) go
short circuit on both legs. It directly shorted 48v of AGM power. The 200a
circuit breaker was useless. It never opened at all.
-Phil
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Friday, July 20, 2007 9:17 AM
Subject: "Tree House" Controller
[EMAIL PROTECTED] wrote:
Yeah, I thought IGBT's might be the one thats I needed. But how do
forklift scr's work? All I want to do is turn voltage on and off really
fast. I guess there really is just no way to do it without high tech
electronics.
If you lower your expectations enough, then a simple PWM controller is
possible. The main tradeoffs are:
- It will be acoustically noisy (you can hear it operating),
- It will be slightly less efficient (a few percent).
- Power will be modest, like a Curtis controller.
- It won't be "idiot proof", i.e. it will have little or no
protection from overtemperature, undervoltage, overcurrent, etc.
- It will have somewhat "lumpy" operation; things like a small
lurch when starting out, or a throttle response that doesn't
match a normal ICE's, etc.
- There will be "surprise" failure modes, due to design or
assembly errors (stuff you don't know when you build it).
SCRs are cheap, rugged, and easy to turn on (even easier than MOSFETs or
IGBTs). The tradeoff is that they are hard to turn off. The classic method
is to have a big inductor, a big capacitor, and 1 or 2 extra big SCRs or
diodes. The circuits are very basic and well documented; it's just that
these are big parts!
could not the IGBTt just be in line with the motor and batteries
switched on and off by a gate current? I'm well aware of the problems
involved with real controllers, it just seems like a solid state
on/off switch could be rigged up without any bells or whistles.
If you're using the IGBT as a solid-state contactor, then there are no
switching loss concerns. You just have to deal with the heat produced by
its 3v drop at full current.
You will always need a freewheel diode. It is easiest to get an IGBT
module that has one built-in, as it will naturally have short leads and be
matched to the IGBT's capabilities.
If you want to duty-cycle modulate that IGBT to make a PWM controller,
then it gets interesting. Now you have to deal with switching losses,
which can exceed conduction losses (twice the heat, which means twice the
cooling and/or having to use the parts at half their ratings). And, you
have to make fast, accurate measurements in noisy high-power switching
circuits, for current limit and voltage protection to work.
I think the trouble with simple cheap controllers is the "tree house"
problem. It goes like this:
1. Kids want a tree house. They know they can scrounge up some scrap
lumber, find a can of rusty nails in the garage, steal dad's hammer
and saw, and build it in a day or two!
2. But dad knows it will be a ramshackle structure, badly built,
probably unsafe, and certainly ugly.
What's likely to happen?
A. Kids don't tell dad. They build it themselves. It takes a week
instead of a month, due to all the "surprises" along the way.
They smash thumbs, get splinters, bend nails, need to scrounge
more materials, but manage to cobble something together. It looks
and works terrible; but they learned a lot and love it anyway.
B. Dad gets involved. He says, "We have to do this right". He makes
plans, buys materials, tries to supervise but winds up doing it
himself because the kid's workmanship is so poor. It takes him
all summer to build it. It looks great and is safe; but the kids
rarely use it; they're off on some other hot new interest.
It's hard for experts to remember that beginners have far lower standards
of quality and performance. The expert knows how to do it "right" -- build
something that even he would be proud to use. But it's very hard for him
to build a "tree house controller" that is disgustingly cheap crude and
primitive.
But the beginner, having no experience with real controllers, may be
perfectly happy with a "tree house controller", thrown together out of
cheap surplus parts, that works but has all sorts of problems.
The middle ground is difficult to achieve. It would be like:
C. Dad supervises, but forces himself to keep his hands in his pockets
and his mouth shut most of the time. He shows them how to use a
hammer and saw, but doesn't do the work for them (so they learn how
to do it themselves). He shows them how to make strong joints so it
won't fall apart, but lets them do it their way (so they learn the
consequences of not doing it right). Dad knows that learning is the
real goal; not the end product itself.
The end result is a tree house that still looks pretty crude; but it is a
heck of a lot stronger and safer that it would have been without adult
supervision. And the kids still love it, because they made it themselves!
--
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 ---
