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Today's Topics:

   1. Re: New motor design will help the EV world! (GWMobile)
   2. Re: cheap cheap cheap!!!!!! (Gilbert, Brian D (GE Infra, Energy))
   3. Re: Finsishing it up mounting the motor (Roland Wiench)
   4. Re: Finshing it up DC/DC (Jeff Major)
   5. Re: Finshing it up DC/DC (Roger Stockton)


Message: 1
Date: Thu, 25 Oct 2007 10:23:21 -0700
Subject: Re: [EVDL] New motor design will help the EV world!
To: Electric Vehicle Discussion List <>
Content-Type: text/plain; charset="us-ascii"; format="flowed"

Any true circuit design would have a board design as well specifically 
to avoid the eddie current problems you mention.
Board design is automated and softre exists that elminates testing 
requirements because it calculates wire route neded to avoid eddies and 
other problems.

> Its not the schematic thats the hard part of the controller design,
> its the board layout and packaging. When you get higher
> voltages/currents, you have eddie currents, noise and other stuff to
> worry about. I'm currently helping some guys in the Portland area
> design/test/build some DC as well as AC controllers. Its not a simple
> thing. Expect to spend months testing/designing and
> retesting/redesigning.
> Not trying to discourage, but trying to shed some light on the harder
> side of things. You may be able to modify that circuit to drive higher
> voltage FETs with higher capacity diodes/caps/etc... so that you could
> use it to drive a higher voltage motor. Hell, with some fancy
> programming, and splitting up small groups of FETS, you could do AC.
> Good luck
> Travis Gintz
> 1986 Honda VFR AC conversion
> Http://
> On 10/25/07, Steven ** <[EMAIL PROTECTED]> wrote:
>>  I've been looking at the motor controller as the prime candidate for 
>> saving
>>  money.  I'm good with a soldering iron.  I just need to know what 
>> parts to
>>  put together.  I did find one diagram for a motor controller (
>>  But it says it's
>>  intended for 24 - 48V input and 200 - 400 amps.  I don't understand 
>> what the
>>  limiting factor is that caps it at 48V.  Anyone have a circuit 
>> diagram for a
>>  controller that handles higher voltage?
>>  I've recruited some Computer Engineers (Computer Engineer = (0.5 * 
>> Computer
>>  Science degree) + (0.5 * Electrical Engineer degree) ) for our EV 
>> project
>>  that will hopefully be able to design a controller.  If we come up 
>> with
>>  something that works, I will quickly post our circuit diagram and any
>>  instructions on my website.
>>  -Steven
>>  On 10/25/07, Dan Frederiksen <[EMAIL PROTECTED]> wrote:
>>  >
>>  > the skilled labor part has been greatly exaggerated. the skill is
>>  > required in the design, not the assembly. just instruction
>>  > and the power electronics for a curtis has been estimated at 80$ in 
>> even
>>  > moderate volume
>>  >
>>  > the battery tech is here too but to be practical we need a big 
>> company
>>  > to make large cheap packs available off the shelf so grease monkeys 
>> can
>>  > just plug it in. a bit like lead acids now.
>>  >
>>  > Dan
>>  >
>>  >
>>  >
>>  > Andrew Kane wrote:
>>  > >       I am a staunch FOSS advocate and believe that the same
>>  > > philosophy should be applied to hardware when applicable, though I
>>  > > concede that for some time to come it will apply in only very rare
>>  > > circumstances. I certainly would not want an EV designed with a 
>> "black
>>  > > box" approach.
>>  > >       However, my previous concerns as to motor controller design 
>> have
>>  > > not been addressed. I reiterate that I am not educated enough to 
>> know
>>  > > much about this subject, but from my reading the cost of 
>> components
>>  > > and skilled labor is an irreducible factor, regardless of the 
>> openness
>>  > > of the design. My belief is that the design should be entirely 
>> open,
>>  > > since that will facilitate improvements as time goes on and the 
>> design
>>  > > gathers eyeballs.
>>  > >        If you, Mr. Hart, know of ways around the problems I have 
>> dimly
>>  > > perceived in the mass-production of motor controllers, I would be
>>  > > eager to hear about them, although I may not have the background 
>> to
>>  > > understand. In the meantime I continue to concede that the battery
>>  > > problem is the main problem.
>>  > >        By the way: Thank you for all you do.
>>  > >
>>  >
>>  > _______________________________________________
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>>  >
>>  >
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Message: 2
Date: Thu, 25 Oct 2007 13:26:10 -0400
From: "Gilbert, Brian D (GE Infra, Energy)" <[EMAIL PROTECTED]>
Subject: Re: [EVDL] cheap cheap cheap!!!!!!
To: "Electric Vehicle Discussion List" <>
Content-Type: text/plain;       charset="us-ascii"

You seem to be arguing that if we could get economy of scale going for
us, AC motors and controllers would be cheap.  You use the semiconductor
industry to try to prove your point, but they have had economy of scale
on their side for decades, and their progress is technology limited, not
scale limited.

The technology for AC controllers and motors is not technology limited,
nor is it scale limited either.  Several companies make AC induction
motors and controllers in the sizes required for EV use, and they make
lots of them for industrial machines.  THEY ARE NOT CHEAP.  In fact,
Otmar's controllers and Advanced DC motors are significantly less

Batteries are the limiting factor right now.  They are technology AND
scale limited.  Even with A123Systems batteries you would need more than
10000 of them (a lot more!) to go 300 miles in a 250wh/m vehicle.  The
Tesla had to use older technology batteries so they could get around the
scale issues, but they have more limited discharge/recharge, can explode
easily, and aren't that cheap anyways.

And how can you say that a quad-core with billions of transistors is
cheap?  Last I checked, the materials going into a processor cost a few
pennies!  $250 for a processor is outrageous!


some truth to that but also som bullshit if that was the case it would
be hard to explain the consumer computer industry where you can have
killer products dirt cheap

go back in time and ask someone to make you a quad core cpu with a
billion transistors at a few gigahertz for 250$ and they might laugh too


Ben wrote:
> Reminds me of that old saying..
> Good, Fast, Cheap: Pick any two (you can't have all three).
> On 10/25/07, wayne alexander <[EMAIL PROTECTED]> wrote:
>> I keep seeing " I want cheap this & that, I dont want to pay alot for
anything for my EV"
>>   well why dont you go out and buy a CNC ststem, plasma cutter, about
20K$ woth of hand tools,  a 14x40 lathe, and start making your own, this
way you wont have to pay for anything.
>>   But asking a business to make or give you "CHEAP" THEY WILL LAUGH
>>   then when some other cheap skate ask you to make some thing cheap
for him, your gonna say "ARE YOU NUTS, YOU KNOW HOW MUCH ALL THIS CRAP
COST ME TO RUN A BUSINESS"   lolololol     Wayne


Message: 3
Date: Thu, 25 Oct 2007 12:11:20 -0600
From: "Roland Wiench" <[EMAIL PROTECTED]>
Subject: Re: [EVDL] Finsishing it up mounting the motor
To: "Electric Vehicle Discussion List" <>
Content-Type: text/plain;       charset="iso-8859-1"

Hello Damon,

If you have your motor side tap for motor mounts, just use a standard engine 
mounts that has a bottom rubber mounting plate and a engine side plate. 
This is what I use.  If you motor holes do not align up right, than use a 
flat bar of steel with tap holes as a adapter.

Install the motor mounts, transmission, and dry fit the unit so that the 
rear transmission mount is setting on the correct position on the 
transmission rear cross member.

Make sure that the transmission yoke is not bottom out into the 
transmission. Look up the specs to see what clearance you need.  This 
clearance is needed, as the rear axle goes up and down which reduces the 
angle of the driven line, which allows it to slip in and out of the 

Make sure that the motor and transmission is level in relationship to the 
differential, NOT INLINE, but is parallel.  There should not be least a 2 
degree angle in the drive line between the yoke of the transmission and the 
yoke of the differential.  If this is not maintain, you will take out the 
needle bearings in the U-joints  bearings, because they will not rotate 

After you have the motor and transmission correctly place, while hanging on 
a engine hoist or some other lift, than you can reference a platform 
position for mounting the motor mounts to.


----- Original Message ----- 
From: "damon henry" <[EMAIL PROTECTED]>
To: "EV List" <>
Sent: Thursday, October 25, 2007 8:54 AM
Subject: [EVDL] Finsishing it up mounting the motor

I could use a little input on issues of mounting my motor.  As soon as I get 
my adaptor plate this will be the first thing I tackle.  My plan is to 
couple the motor and transmission together then mount the transmission back 
in place and see how it all needs to sit before fabricating anything.  I 
have two potential mounting points, the original motor mounts, and a frame 
member that looks like it will end up sitting under the motor in a very 
convenient location.  My motor has a flat metal mount welding on the bottom 
plus several tapped holes in the case that we put there while we had it all 
apart to be used during mounting.

So I won't have a lot of specifics until it is all hanging in place, but I 
do have a couple of general questions.  First, what considerations are 
important when deciding how to mount the motor.  I know that providing 
resistance against the torque of the motor is a must, which is why we tapped 
the holes in the motor case.  Also, should everything be mounted with some 
kind of hard rubber insulator to keep vibration from being transferred to 
the frame?  What kind of clever things have you tried that might work well 
for me, and what kind of mistakes have been made that I should be sure to 

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Message: 4
Date: Thu, 25 Oct 2007 11:21:44 -0700 (PDT)
From: Jeff Major <[EMAIL PROTECTED]>
Subject: Re: [EVDL] Finshing it up DC/DC
To: Electric Vehicle Discussion List <>
Content-Type: text/plain; charset=iso-8859-1

Hi Damon,

I think voltage doublers only work on AC when
rectified to DC.  So would not work off the battery.

Jeff M

--- damon henry <[EMAIL PROTECTED]> wrote:

> The last option I have been considering is a voltage
> doubler to feed a regular proven EV style DC/DC like
> an IOTA.  This has a few advantages that I like. 
> First, there is a good chance that this truck may
> end up at 144 volts in the future at which point I
> could just remove the voltage doubler.  I'm going to
> try the truck at 72 volts for now and see how I like
> it.  Second, this option feels like a complete
> solution, where the others feel like they are just
> adequate. The main problem is that I don't know what
> it takes to build a voltage doubler, although I'm
> under the impression that they are fairly simple
> circuits, but perhaps they are a bit trickier at
> these current levels.  If the DC/DC is good for 40
> or 50 amps that means the voltage doubler would have
> to be built for twice that.
> Any comments appreciated.  Or if you know of a good
> DC/DC that that operates well in the 60 - 90 volt
> range and that is easy to work with and readily
> available let me know.
> thanks
> damon

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Message: 5
Date: Thu, 25 Oct 2007 11:58:56 -0700
From: Roger Stockton <[EMAIL PROTECTED]>
Subject: Re: [EVDL] Finshing it up DC/DC
To: "'Electric Vehicle Discussion List'" <>
Content-Type: text/plain; charset="us-ascii"

damon henry wrote:

> Any comments appreciated.  Or if you know of a good DC/DC
> that that operates well in the 60 - 90 volt range and that is
> easy to work with and readily available let me know.

Check out Surepower <>; they're in your area and have 
good DC/DCs.  The 71030i (used in GEM NEVs) delivers [EMAIL PROTECTED] and 
works with battery packs from 72-96V nominal.

As others have noted, a voltage doubler works on AC only.  If you have a 30A 
output DC/DC delivering 12V from 144V input, then it draws about 2.5A @ 144V, 
or about 5A @ 72V on the battery side of a voltage step up device.  This is far 
more managable a current level than you had thought.  While a voltage doubler 
would not work, it is possible to use a vibrator circuit to chop the 72V DC 
allowing it to be stepped up by a transformer.  I would suggest that unless you 
have lots more time than money you would be much better off to just buy a 
SurePower DC/DC and know that it will just work ;^>




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End of EV Digest, Vol 3, Issue 72

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