EV Digest 2396

Topics covered in this issue include:

  1) Re: Hardware for regen/dynamic braking set up?
        by "Cliff Rassweiler" <[EMAIL PROTECTED]>
  2) Charging in Fremont/Newark, CA (the "Right Bay"?)
        by Edward Ang <[EMAIL PROTECTED]>
  3) Re: There's no stopping now!
        by [EMAIL PROTECTED]
  4) RE: Hardware for regen/dynamic braking set up?
        by "Andre Blanchard" <[EMAIL PROTECTED]>
  5) Q on Series Motor
        by Edward Ang <[EMAIL PROTECTED]>
  6) Re: Hardware for regen/dynamic braking set up?
        by "Cliff Rassweiler" <[EMAIL PROTECTED]>
  7) RE: Hardware for regen/dynamic braking set up?
        by "Chris Tromley" <[EMAIL PROTECTED]>
  8) RE: Hardware for regen/dynamic braking set up?
        by "Andre Blanchard" <[EMAIL PROTECTED]>
  9) RE: Hardware for regen/dynamic braking set up?
        by "Andre Blanchard" <[EMAIL PROTECTED]>
 10) Re: Hardware for regen/dynamic braking set up?
        by "Cliff Rassweiler" <[EMAIL PROTECTED]>
 11) Re: Hardware for regen/dynamic braking set up?
        by "Cliff Rassweiler" <[EMAIL PROTECTED]>
 12) Re: Hardware for regen/dynamic braking set up?
        by "Cliff Rassweiler" <[EMAIL PROTECTED]>
 13) RE: Hardware for regen/dynamic braking set up?
        by "Andre Blanchard" <[EMAIL PROTECTED]>
 14) Re: Q on Series Motor
        by "VanDerWal, Peter MSgt" <[EMAIL PROTECTED]>
 15) Re: Hardware for regen/dynamic braking set up?
        by "Thomas Shay" <[EMAIL PROTECTED]>
 16) Re: It's Dead, Jim...or is it?
        by Victor Tikhonov <[EMAIL PROTECTED]>
 17) Re: Q on Series Motor
        by Edward Ang <[EMAIL PROTECTED]>
 18) Re: EVLN(Hey Saddam! Kiss My Gass, Who said EVs can't go fast?)
        by "Chuck Hursch" <[EMAIL PROTECTED]>
 19) Re: Hardware for regen/dynamic braking set up?
        by Victor Tikhonov <[EMAIL PROTECTED]>
 20) Re: It's Dead, Jim...or is it?/ Water pump.
        by Otmar <[EMAIL PROTECTED]>
 21) Re: Hardware for regen/dynamic braking set up?
        by Victor Tikhonov <[EMAIL PROTECTED]>
 22) Re: The little Rudman that could.
        by "Lawrence Rhodes" <[EMAIL PROTECTED]>
 23) Caution: Re: Hardware for regen/dynamic braking set up?
        by Victor Tikhonov <[EMAIL PROTECTED]>
 24) Re: Hardware for regen/dynamic braking set up?
        by "Cliff Rassweiler" <[EMAIL PROTECTED]>
 25) Re: Hardware for regen/dynamic braking set up?
        by Victor Tikhonov <[EMAIL PROTECTED]>
--- Begin Message ---
Andre,


> I would look at a simple dump or diversion regulator type of system that
> just turns on the resistors as the battery voltage comes up.  This would
be
> completely separate from the braking system, its only job would be to keep
> the battery voltage from going to high, it would be set at a voltage just
> under the limit at witch the braking controller starts to limit braking
> current.  Have resistors (one each) that would pull about 40, 80, 160, and
> 320 amps.  A simple controller could then turn on the necessary load in a
> binary pattern proportional to the voltage.  Something like at 400 volts
the
> 40 amp resistor is on, at 401 volts the 80 resistor is on, at 402 volts
the
> 40 and 80 amp resistors are on etc..  It works fine on my wind generator
> system, but that is only 1000 watts at 12 volts.

What specifically makes up a dump or diversion regulator. I can sense the
voltage and send a signal to tell it to turn on, but what is the part I
need? What does your wind generator use?

> Or you could get Rich to build a set of very high power regs and do it on
a
> per battery basis.

This is probably the ultimate system. Each cell has it's own resistor. We
even pictured making the resistor an integral part of a tube. Each tube
connects to the tube on the battery next to it and forms a cooling system
circulating cooling fluid to a radiator. This would allow very short wires
battery to resistor. For the perfect system, we would need to sense temp,
current, voltage, and probably calculate SOC. Each cell would be
individually charged. So all we need are 180 smart chips and 180 cheap 700
amp 2.5 volt diversion regulators.<g>

Cliff

www.ProEV.com
--- End Message ---
--- Begin Message ---
Fremont Hub
I found 110V outlets at Fremont Hub.  There are at
least 3 outlets under the trees in front of Radio
Shack.  There are outlets also on the light poles, but
they only have power when the lights are on.  I will
double check again those under the trees to see if
they have power when the lights are off.

I gained 5 miles having a 40-min dinner over there
last evening :)


NewPark Mall
There are at least 3 110V outlets in the parking
garage next to Target.  2 on the lowest level and one
on second level.  There are outlets on all light pole
on the highest level.  All of these are always on.

Ed Ang

__________________________________________________
Do you Yahoo!?
HotJobs - Search new jobs daily now
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--- End Message ---
--- Begin Message ---
In a message dated 29/10/02 22:58:40 GMT Standard Time, 
[EMAIL PROTECTED] writes:

> Last Saturday, I started a race against time to investigate, before
> the forecast bad weather arrived ( nasty storm, with 90+ mph gusts ).
> Found that the master cyclinder wouldn't pump fluid out, even with the
> pipes disconnected. Darn it all, it was the master cylinder that was
> causing the hassle!

Wrong pushrod length. The piston isn't returning far enough to open the 
input/bleed ports. Been there done that. In my case it was right on the 
margin, normally fine but binding up as the brakes heated.


Paul Compton
BVS technical officer www.bvs.org.uk
www.sciroccoev.co.uk
--- End Message ---
--- Begin Message ---
What can the split be side to side when braking into a corner?

Andre' B.  [EMAIL PROTECTED]
If something cannot be defined, it does not exist.
Isaac Newton

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:owner-ev@;listproc.sjsu.edu]On
Behalf Of Rich Rudman
Sent: Wednesday, October 30, 2002 11:45 AM
To: [EMAIL PROTECTED]
Subject: Re: Hardware for regen/dynamic braking set up?

Yea track braking is 1 G plus, and up to 3 Gs if you have ground
effects, and 90% of it is on the front tires.
Front drive is required to get this with Regen.


--
Rich Rudman
Manzanita Micro
www.manzanitamicro.com
1-360-297-7383,Cell 1-360-620-6266
--- End Message ---
--- Begin Message ---
Any reason why we can't power the field winding and
the armature separately?  Since most series motors
have different terminals for field winding and for
armature to allow for reversed rotation operation,
could we power them from different power source (or in
parallel) instead of in series?  We might need a lower
voltage to avoid arcing at the brushes, but could this
be done?

If this is possible, a 144V series motor could be run
at 72V and still give about the same power?

Just want to learn more.

Thank you.

Ed Ang

__________________________________________________
Do you Yahoo!?
HotJobs - Search new jobs daily now
http://hotjobs.yahoo.com/
--- End Message ---
--- Begin Message ---
> >> For a race car, I assume weight is important... Let it boil off the
> >> water, so you can carry just enough to finish the race.
>
> > I suspect race officials will take a dim view of us emitting clouds
> > of steam everytime we brake.
>
> Depending on the ambient humidity, the steam wouldn't be visible. The
> air behind the car is just more humid than in front of it. :-)

Too bad. I was beginning to get enamored with this idea. Two cars dive into
the corner. A cloud of steam. Only one car emerges.

>
> > The motor controller is intelligent enough to give us the amount of
> > current we ask for, but it has no provision for splitting those amps
> > to anywhere other than the batteries.
>
> That part is easy. You would just have your load resistors in parallel
> with the batteries. The controller delivers all its regen power to the
> batteries. A second controller watches battery voltage; if too high for
> the current, it adds the load resistors as needed.

What should I use for a second controller? Something like a 400 volt Zilla?
I could run an analog signal in place of the throttle pot to control it.
Wouldn't I need an inductor with the resistor?

>
> > use some sort of electronic one/off switch (SCRs?) to cut in different
> > resistors as needed and let the controller do the fine control.
>
> SCRs are easy to turn on, but won't turn off until the current in them
> goes to zero. This happens automatically in an AC circuit; you could put
> SCRs and load resistors directly on your AC motor. But SCRs would be a
> poor choice to switch load resistors in the DC side.

Ok, SCRs would not be a good choice on the DC side. What would?

>
> > For example, say the SOC calcs tell us that 100 amps is what the
> > batteries will accept at this time. The braking signal is calling
> > for 550 amps to slow the car. We signal 5 of our resistors which
> > will each take 100 amps at 400 volts to join the circuit... the
> > batteries are only getting around 50 amps, even though we want them
> > to get 100 amps.
>
> That is not a problem. The batteries don't care if the instantaneous
> current is 100 amps; only that the average be 50 amps. You could
> alternately apply 0-100-0-100 amps by switching one of your load
> resistors on and off.
>
> In practice, the regen current is going to vary rapidly depending on
> driver input. The battery voltage is also going to be changing very
> quickly. The batteries only care that the voltage is not too high for a
> given state of charge. So all you need is a giant version of a Rudman
> regulator, that switches the load resistor on/off as need to keep the
> batteries below X volts.

So basically I can use one resistor and switch it on and off rapidly to keep
the batteries below X volts. Which is basically the DC traction controller
above controlled by voltage sensing?

Cliff
--- End Message ---
--- Begin Message ---
Andre Blanchard wrote:

> What can the split be side to side when braking into a corner?

That's where things get really interesting.  Regen acts on the ring gear
(assuming a differential is involved), not the wheels.  If it's an open
differential and one wheel locks on a slick spot, the ring gear will
turn half as fast as it would if both wheels were turning.  If the
differential is some sort of limited-slip type, the nature of the
differential will have a substantial effect on side-to-side balance.

You're asking components that were never designed for braking to start
performing as a braking system.  Under extreme conditions, where
delicate control is vital.  Not saying it can't be done, but you're
talking about a serious development project.

Chris
--- End Message ---
--- Begin Message ---
The system on my wind generator is just a single resistor connected to a
mosfet switch, the switch is controlled by a simple voltage comparator.  I
just described the binary resistor setup because you wanted a little better
control.  That will require a little more like a micro or could possibly use
an A/D chip in a free running mode with the switches connected to the output
bits.

But actually a PWM system like Lee describes would provide very smooth
control.

Andre' B.  [EMAIL PROTECTED]
If something cannot be defined, it does not exist.
Isaac Newton

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:owner-ev@;listproc.sjsu.edu]On
Behalf Of Cliff Rassweiler
Sent: Wednesday, October 30, 2002 12:03 PM
To: [EMAIL PROTECTED]
Subject: Re: Hardware for regen/dynamic braking set up?

Andre,


> I would look at a simple dump or diversion regulator type of system that
> just turns on the resistors as the battery voltage comes up.  This would
be
> completely separate from the braking system, its only job would be to keep
> the battery voltage from going to high, it would be set at a voltage just
> under the limit at witch the braking controller starts to limit braking
> current.  Have resistors (one each) that would pull about 40, 80, 160, and
> 320 amps.  A simple controller could then turn on the necessary load in a
> binary pattern proportional to the voltage.  Something like at 400 volts
the
> 40 amp resistor is on, at 401 volts the 80 resistor is on, at 402 volts
the
> 40 and 80 amp resistors are on etc..  It works fine on my wind generator
> system, but that is only 1000 watts at 12 volts.

What specifically makes up a dump or diversion regulator. I can sense the
voltage and send a signal to tell it to turn on, but what is the part I
need? What does your wind generator use?

> Or you could get Rich to build a set of very high power regs and do it on
a
> per battery basis.

This is probably the ultimate system. Each cell has it's own resistor. We
even pictured making the resistor an integral part of a tube. Each tube
connects to the tube on the battery next to it and forms a cooling system
circulating cooling fluid to a radiator. This would allow very short wires
battery to resistor. For the perfect system, we would need to sense temp,
current, voltage, and probably calculate SOC. Each cell would be
individually charged. So all we need are 180 smart chips and 180 cheap 700
amp 2.5 volt diversion regulators.<g>

Cliff

www.ProEV.com
--- End Message ---
--- Begin Message ---
I have a vision of the resistors and the water in a small closed space.
Hit the brakes water heats up well about atmospheric pressure boiling point
but since the entire available space is used by the water already it cannot
boil, but it will build up pressure.  Then when you come out of the corner a
valve opens water bursts into steam and exits through a nozzle.  Helping to
accelerate the car.

I think there was/is someone that runs such a car at a drag track.  His
closed space holds several gallons of water that is heated up before the
race and is the sole source of power for the car.

Andre' B.  [EMAIL PROTECTED]
If something cannot be defined, it does not exist.
Isaac Newton

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:owner-ev@;listproc.sjsu.edu]On
Behalf Of Cliff Rassweiler
Sent: Wednesday, October 30, 2002 12:45 PM
To: [EMAIL PROTECTED]
Subject: Re: Hardware for regen/dynamic braking set up?

> >> For a race car, I assume weight is important... Let it boil off the
> >> water, so you can carry just enough to finish the race.
>
> > I suspect race officials will take a dim view of us emitting clouds
> > of steam everytime we brake.
>
> Depending on the ambient humidity, the steam wouldn't be visible. The
> air behind the car is just more humid than in front of it. :-)

Too bad. I was beginning to get enamored with this idea. Two cars dive into
the corner. A cloud of steam. Only one car emerges.

<<  snip  >>
--- End Message ---
--- Begin Message ---
Rich,

> Cliff What kinda battereis???
> Optimas I thought or Gennies. I have it written down some wheres. Any
> good AGM Lead acid battery will suck up what it can make.

 Cyclons.

  >After you
> have about 1 Kwhr out of the stack, the batteries will take a lot more
> than 250Kw.

This would make life easier but I have a hard time picturing them accepting
700 amps without complaint.

>Your inverter drive has a over voltage buss set point.

400 Volts

 >It
> can be set to back off the regen at a programmed voltage point. simply
> have your "BRAKING resistors" kick in about 2 volt below the cut back
> point.

What should I use to connect the resistors to the circuit?

 > GET a Locomotive sized braking resistor, have it in  water, and
> you can suck up about 180 Kw that way.

Good. Where do I find a locomotive size resistor? How much does it weigh?

>We do it testing DC controllers.
> My guess is that you won't need it once the first lap is over with.

>
> Ummm don't over voltge the charger..... I won't like that....

The charger will sit in the pits safe from regen experiments.

>
> Your chassis will be in my hands for start of build up Friday.... the
> day I am moving....
>
>
>
>
> --
> Rich Rudman
> Manzanita Micro
> www.manzanitamicro.com
> 1-360-297-7383,Cell 1-360-620-6266

>
--- End Message ---
--- Begin Message ---
Hi Chris,

> Max braking involves a very subtle balance of very large forces.  The
> forces, and therefore the balance, are constantly changing in any
> braking event, and will be different at different points on the track.
> A good driver plays the brake pedal just as delicately as he plays the
> accelerator or steering wheel.  *Everything* he does is on the ragged
> edge of adhesion.
>
> He can do this with a hydraulic brake system because it provides
> excellent, real-time feedback.  Will your high-power regen do the same?

A valid concern and one we won't be able to answer until we get the car on
the track. A big design goal is to have the regen pedal deliver a constant
response regardless of SOC or motor RPM. Whether the electronics calculating
everything will give sufficient response time to emulate hydraulic brakes is
something we will have see.

> Since hydraulic brakes *must* be part of the system, you seem to be
> combining regen with hydraulic brakes to get your overall braking
> performance.  The difficulty will be in getting the two to work well
> together on the track, even after all the control issues are solved.

Our solution is simple and low tech. All our drivers are skilled left foot
brakers. The regen pedal goes in place of the clutch pedal. To slow the car,
the driver regens with his left foot. 10% pedal, 10% of max regen, etc. If
he needs addition stopping power beyond max regen, his right foot moves to
the brake pedal and modulates that.

Cliff

www.ProEV.com
--- End Message ---
--- Begin Message ---
Rich

> Like I just said..... you batteries will take a LOT more amps than you
> expect. Yts and Gennies can take 15.5  to 16 volts each for 2-10
> seconds. Your brake current will be your limit NOT what your batteries
> can take. Once off the %90 charged shelf, dump pack currents are OK.

Sounds like 400 volt Max bus voltage will be the controlling factor. The
usual
racer's Catch-22; The higher voltage pack we run, the better our torque
curve looks. The lower voltage pack we run, the higher voltage we can show
the individual batteries and the more amps we can recapture under regen.


Cliff

www.ProEV.com
--- End Message ---
--- Begin Message ---
Should have added the disclaimer, that heating water in a closed container
without knowing exactly what you are doing is a very good way to get dead.

Andre' B.  [EMAIL PROTECTED]
If something cannot be defined, it does not exist.
Isaac Newton

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:owner-ev@;listproc.sjsu.edu]On
Behalf Of Andre Blanchard
Sent: Wednesday, October 30, 2002 1:25 PM
To: [EMAIL PROTECTED]
Subject: RE: Hardware for regen/dynamic braking set up?

I have a vision of the resistors and the water in a small closed space.
Hit the brakes water heats up well about atmospheric pressure boiling point
but since the entire available space is used by the water already it cannot
boil, but it will build up pressure.  Then when you come out of the corner a
valve opens water bursts into steam and exits through a nozzle.  Helping to
accelerate the car.

I think there was/is someone that runs such a car at a drag track.  His
closed space holds several gallons of water that is heated up before the
race and is the sole source of power for the car.

Andre' B.  [EMAIL PROTECTED]
If something cannot be defined, it does not exist.
Isaac Newton

--- End Message ---
--- Begin Message ---
>Any reason why we can't power the field winding and
>the armature separately? 

Some regen controllers actually do this (in regen only though).

>Since most series motors
>have different terminals for field winding and for
>armature to allow for reversed rotation operation,
>could we power them from different power source (or in
>parallel) instead of in series?

The voltage across the field coils in a series motor is typically only a
couple volts.  Hundreds of amps but only a couple volts.  The requirements
for a field only power source would be virtually the same as for the whole
motor, in other words you would need TWO high current controllers.  The
current requirements are the same whether it's one or two controllers so you
basically double your controller cost.

> We might need a lower
>voltage to avoid arcing at the brushes, but could this
>be done?

Actually you are going to get arcing (even at low voltage) if fields
strength gets out of sync(relative power) with the armature strength.  Wired
in series they automatically stay in sync.  
This pretty much kills your idea right here, there is no real advantage to
powering them separately if you need to keep them in sync.

>If this is possible, a 144V series motor could be run
>at 72V and still give about the same power?

Not unless you rewound the motor.  
As is, 72V across the field would cause it to draw thousands (possibly tens
of thousands) of amps and probably melt quickly unless you used a controller
to reduce the current.  Reducing the current will reduce the voltage until
you only have a couple volts flowing.
This is effectively no different that powering the field in series.

Before the field melts it would be way over saturated, this means that it
won't produce a proportionally larger magnetic field.  You'll have 20-30
times the current going through it that it's rated to handle, but it's field
strength will only be maybe 5 times stronger (total swag here) 
With only 72V on the armature coils they will only produce about 1/2 their
potential field strength.
Net result is slightly more power than running the motor as a series motor
on 72V, probably lots of arcing, melted fields coils/cabling/ or batteries
and far less power than running the motor on 144V.

>Just want to learn more.
Nice idea, what you are describing is called a shunt or separately excited
motor (depending on how it's wired).  These types of motors have field coils
that use much thinner wire with many more coils.  The coils are then powered
with high voltage / low current instead of the low voltage / high current
that series motors use in their field coils. 

Magnetic field strength is determined by the amount of current flowing
multiplied by the number of coils.  100 amps through a coil with 1 loop
produces about the same field strength as 10 amps through 10 loops (assuming
equal diameter loops).  

Longer thinner wire has more resistance so it takes more voltage to push 10
amps through 10 thin coils than it does to push 100 amps through 1 thick
coil.  Plus the spinning armature coil produces back EMF in the field coils,
more coils equals more BEMF which means more applied voltage to overcome the
BEMF.
--- End Message ---
--- Begin Message ---
I'm puzzled about the reason to brake the car so hard.
How much room is there to decelerate on a typical
1/4 mile drag strip?
--- End Message ---
--- Begin Message ---
Christopher Meier wrote:
> 
> John, have you considered that the time may be right to form a
> custom, high-end, EV conversion business?  With components
> that are available now (Warp, PFC, Godzilla, Siemens, etc),
> and your wonderful 'salesmanship' and design/crafting ability
> and attention to detail,

John, just don't use fish tank water pumps for cars, OK?  :)

Victor
--- End Message ---
--- Begin Message ---
Thanks!  I have only taken apart permanent magnet
motors before, but not shunt or series or compound
motors.  I know the theory, but it was hard for me to
visualize their physical differences.  Good learning!

Ed Ang

--- "VanDerWal, Peter MSgt" <[EMAIL PROTECTED]>
wrote:
> >Any reason why we can't power the field winding and
> >the armature separately? 
> 
> Some regen controllers actually do this (in regen
> only though).
> 
> >Since most series motors
> >have different terminals for field winding and for
> >armature to allow for reversed rotation operation,
> >could we power them from different power source (or
> in
> >parallel) instead of in series?
> 
> The voltage across the field coils in a series motor
> is typically only a
> couple volts.  Hundreds of amps but only a couple
> volts.  The requirements
> for a field only power source would be virtually the
> same as for the whole
> motor, in other words you would need TWO high
> current controllers.  The
> current requirements are the same whether it's one
> or two controllers so you
> basically double your controller cost.
> 
> > We might need a lower
> >voltage to avoid arcing at the brushes, but could
> this
> >be done?
> 
> Actually you are going to get arcing (even at low
> voltage) if fields
> strength gets out of sync(relative power) with the
> armature strength.  Wired
> in series they automatically stay in sync.  
> This pretty much kills your idea right here, there
> is no real advantage to
> powering them separately if you need to keep them in
> sync.
> 
> >If this is possible, a 144V series motor could be
> run
> >at 72V and still give about the same power?
> 
> Not unless you rewound the motor.  
> As is, 72V across the field would cause it to draw
> thousands (possibly tens
> of thousands) of amps and probably melt quickly
> unless you used a controller
> to reduce the current.  Reducing the current will
> reduce the voltage until
> you only have a couple volts flowing.
> This is effectively no different that powering the
> field in series.
> 
> Before the field melts it would be way over
> saturated, this means that it
> won't produce a proportionally larger magnetic
> field.  You'll have 20-30
> times the current going through it that it's rated
> to handle, but it's field
> strength will only be maybe 5 times stronger (total
> swag here) 
> With only 72V on the armature coils they will only
> produce about 1/2 their
> potential field strength.
> Net result is slightly more power than running the
> motor as a series motor
> on 72V, probably lots of arcing, melted fields
> coils/cabling/ or batteries
> and far less power than running the motor on 144V.
> 
> >Just want to learn more.
> Nice idea, what you are describing is called a shunt
> or separately excited
> motor (depending on how it's wired).  These types of
> motors have field coils
> that use much thinner wire with many more coils. 
> The coils are then powered
> with high voltage / low current instead of the low
> voltage / high current
> that series motors use in their field coils. 
> 
> Magnetic field strength is determined by the amount
> of current flowing
> multiplied by the number of coils.  100 amps through
> a coil with 1 loop
> produces about the same field strength as 10 amps
> through 10 loops (assuming
> equal diameter loops).  
> 
> Longer thinner wire has more resistance so it takes
> more voltage to push 10
> amps through 10 thin coils than it does to push 100
> amps through 1 thick
> coil.  Plus the spinning armature coil produces back
> EMF in the field coils,
> more coils equals more BEMF which means more applied
> voltage to overcome the
> BEMF.
> 


__________________________________________________
Do you Yahoo!?
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--- End Message ---
--- Begin Message ---
I have one of these Kiss My Gass stickers for sale in the Bay
Area, and John Maggio (the creator) has two more (as of last
night).  An image of the sticker can be found at
www.geocities.com/nbeaa/sale.htm, once I get the page uploaded
here in a few minutes.

Chuck Hursch
Larkspur, CA
www.geocities.com/nbeaa
http://www.austinev.org/evalbum/339.html

----- Original Message -----
From: Bruce EVangel Parmenter <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>
Cc: <[EMAIL PROTECTED]>
Sent: Sunday, October 06, 2002 3:00 PM
Subject: EVLN(Hey Saddam! Kiss My Gass, Who said EVs can't go
fast?)


> EVLN(Hey Saddam! Kiss My Gass, Who said EVs can't go fast?)
> [The Internet Electric Vehicle List News. For Public EV
>  informational purposes. Contact publication for reprint
rights.]
>  --- {EVangel}
>
> -[edited]
> From:"john maggio" <[EMAIL PROTECTED]>
> Date:Thu, 3 Oct 2002 21:23:13 -0400 (EDT)
> Subject:Re: th!nk ev car
>
> I'm a participant in the NY State Power Authority's program
> here in upstate New York. There are presently about 80 of
> 100 Ford Th!nk cars on lease between Westchester County,
> Queens and Long Island. I have the longest drive to the
> train station (33 miles RT over several mountians).
>
> I average 175 miles a week and have put on her over 4150
> mies since 3/8/02. I take it on back roads, main routes and
even
> have had it on the interstate, all with very satisfactory
> results. In fact, I told my Ford dealer I wanted the 2003
> model #0001 when it came off the line, that's how much I
> love my car (I have the gray one).
>
> I too, am dismayed and disappointed by Ford's decision to
> drop the Th!nk program. Whle I think the upcoming protest
> will produce some favorable press, perhaps the best way to
> get Bll Ford's attendtion is to use a different strategy...
> Namely, the stockholders. It's a publicly traded company,
> right?
>
> Ford sunk over $100 million into Th!nk and has
> nothing to show for it except 1000 cars. So? Why don't we
> all get the message out that we shouldn't be talking to Ford
> but to the stockholders.  After all, when the lease's are
> up, Ford will spend several hundred thounsand dollars to
> ship them back to Norway and junk them.
>
> My idea is why not
> petition the Ford shareholders to force Ford to sell the
> Norway and USA plants/research centers to the employees for
> a fair sum (likea LLP or LLC) and run it as an employee
> owned compan. In the meantime, sell the Th!nk's to the lease
> holders for say, $10,000 or $15,000. I'm sure with some
> persuation, we can get waivers for the cars. Meantime, the
> sharholders can see at least some return for all the money
> Ford wasted.
>
> Maybe some artculated person from EV
> World or a buch or Th!nk owners can get to the shareholder's
> meeting and voice their suggestions about Th!nk. I would. I
> also would thik I'm gonna cry when I have to give my "Dusty
> Duck" (as the kids call it) up. Unless I hold it for ransom,
> or some other desprite measure.
>
> Thanks for your time but here in NY, we are few and far
> between with no concerted efforts like you guys (and gals)
> in California. Feel free to use my ideas as you wish and if
> you desire, keep in touch.
>
> BTW... Had the car on I-84 tonight. Ford gave me a loaner
> because mines in the shop because of a systems fault. The
> loaner has big white letters on the rear window: "Th!nk
> Electric, Scarsdale Ford". Here I am doing 56 when this
> trucker comes barreling along at better than 80 in the left
> lane. Passes me 'bout half a trailer lenght when he slams on
> the brakes.
>
> Blue brake shoe smoke swirling. Wheels locked
> on wet pavement. Serves behind me and stays there for about
> 4 miles. Finally builds up speed and passes me. I can only
> guess that he read the sign and got behind me to check the
> car out as he leaned on his horn, flashed his lights and
> waved.
>
> He must've been on the CB cause after that, every
> trucker who passed me gave me a good horn show and a thumbs
> up signs or wave.  Funniest thing you ever saw.
>
> Who said an EV can't go fast?
>
> Regards...
>
> John Maggio
> Pawling, NY
>
> PS: I had made up for my car a bumper sticker that reads:
>
> "Hey Saddam... Kiss My Gass. I Own An Electric Car."
> (flanked by the American flag)
> If you'd like some, give me your address.
> -
>
>
>
>
> =====
> ' ____
> ~/__|o\__
> '@----- @'---(=
> . http://geocities.com/brucedp
> . EV List Editor & RE newswires
> . (originator of the above EV ascci art)
> =====
>
> __________________________________________________
> Yahoo! - We Remember
> 9-11: A tribute to the more than 3,000 lives lost
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--- End Message ---
--- Begin Message ---

Cliff Rassweiler wrote:
> 
> Hi,
> 
> We are designing a regen/dynamic braking system for our race car to try and
> return the maximum power to our batteries without blowing them up. We have
> one motor per axle capable of producing up to 320 amps each. We have a data
> acquisition system capable of reading currents and voltages and
> temperatures, calculating SOC, and outputting digital or analogue control
> signals. What we need is a system to take the power in excess of what the
> batteries can accept and burn it off.
> 
> Any suggestions on how to build braking resistors capable of burning off a
> maximum of  256kw (640 amps X 400 volts). I am thinking some kind of liquid
> cooled array but what liquid and what resistors? What is the best hardware
> to control how much power goes to the resistors and how much goes to the
> battery?
> 
> My understanding of how the regenerative system works on our Siemens AC
> motors is that the brake pedal signal tells the controller that it wants say
> 50% of braking power. The controller translates that into current (50% of
> 320 amps max current is 160) and then raises it's output voltage until
> either 160 volts flow into the batteries or the voltage hits the max
> allowed. (Victor, feel free to correct me if I have this wrong).

Yes you are absolutely correct.
You meant 160 Amps flow into batteries, not volts. 

> 
> We have been throwing around a number of ideas. I would love to hear what
> list members suggest.

Do you want to burn extra energy just because don't want to use 
mechanical disk brakes and use motors as "electric brakes" even if 
the batteries are full?
 
> Cliff
> 
> www.ProEV.com
--- End Message ---
--- Begin Message ---
John, just don't use fish tank water pumps for cars, OK?  :)

Victor
I've been using one for over 5 years now, it's the best solution that I know of.
It's reliable. Brushless construction, and it's made to run years continuous.
Unlike automotive water pumps, there's no high temperature to worry about.
It's quiet. People with fish tanks don't like noise in the house. Just like EVs.
It's submersible which makes it very easy to install, just drop it in the reservoir and run hoses out the top, no leaks.
It pumps plenty of water to cool a Zilla.
It does require a pocket inverter to run, but hey, that's one inexpensive AC drive for a water pump!

Here's what I use:
http://www.mops.on.ca/products/PHAS-MJ250.HTML

So Victor, I'm curious why should one not use one of these?

-Otmar-

http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
Rod, Victor chimes in here

Rod Hower wrote:
> 
> Cliff,
> 
> You will also have mechanical brakes?  I would think this would be required
> for racing.
> The controller should have two protection features that are programmable
> (if
> it doesn't it should).
> First is brake current limit.  This may depend on what the control can take
> or
> the batteries.

Programmable: motor braking current value, the motor current ramp dA/dt, 
the RPM point at which it starts decreasing (toward 0 RPM), battery 
charging current limit during regen, and I believe battery charging 
current ramp dA/dt (not sure about this one).

> Second is voltage limit.  The braking (regen) algorithm should reduce duty
> cycle when the bus voltage gets too high.  That means less brake current
> as well.

Of course, this is programmable: voltage value as well as damping 
(overshoot behavior) by Kp controller parameters.

> Some how you will have to integrate a transducer on the brake pedal
> to indicate how fast you want to stop.

dA/dt is programmable, so if you slam on the brakes, regen 
current will increase gradually at desired rate if you wish.
Not sure if you want it this way though.

> When the controller can not provide the braking requested by the operator,
> the mechanical brakes must apply greater force.
> So now you have your 'brake resistor' ie, air cooled friction brakes!
> Rod

If inverters provide regen current resulting loss of traction, no
mechanical
brakes needed (for routine braking, just as emergency).
 
> Lee,
> 
> Thank you for the response.
> 
> > Cliff Rassweiler wrote:
> > > We are designing a regen/dynamic braking system for our race car to
> > > try and return the maximum power to our batteries without blowing
> > > them up... What we need is a system to take the power in excess of
> > > what the batteries can accept and burn it off.
> > >
> > > Any suggestions on how to build braking resistors capable of burning
> > > off a maximum of 256kw (640 amps X 400 volts)?
> >
> > Impressive specs! I hope you can solve all the technological and
> > reliability problems such a complex system entails.
> 
> We hope so too. We are keeping our brake system seperate though<g>.
> 
> > For a race car, I assume weight is important. In that case, some type of
> > water-cooled resistor is probably the best choice. Let it boil off the
> > water, so you can carry just enough to finish the race.
> 
> I suspect race officials will take a dim view of us emitting clouds of
> steam
> everytime we brake. I was thinking more in terms of an enclosed system with
> a radiator to cool the heated fluid.
> 
> > > What is the best hardware to control how much power goes to the
> > > resistors and how much goes to the battery?
> >
> > "Best" requires an immense amount of knowledge and experience about the
> > system. Your motor controller is probably your first choice.
> 
> The motor controller is inteligent enough to give us the amount of current
> we ask for, but it has no provision for splitting those amps to anywhere
> other than the batteries. The scheme that seems to make the most use of the
> controller's smarts is to use some sort of electonic one/off switch (SCRs?)
> to cut in different resistors as needed and let the controller do the fine
> control.
> 
> For example say the SOC calcs tell us that 100 amps is what the batteries
> will accept at this time. The braking signal is calling for 550 amps to
> slow
> the car. We signal 5 of our resistors which will each take 100 amps at 400
> volts to join the circuit. This means that if the controller goes to it's
> maxium of 400 volts, it will get a current of 600 amps. Instead the
> controller adjusts the voltage to get it's 550 amp current with around 50
> amps going to the batteries.
> 
> This isn't as exact as we would like. In this example the batteries are
> only
> getting around 50 amps, even though we want them to get 100 amps. We could
> refine the concept by using either more smaller resistors or a mix of
> different value resistors.
> 
> What do you think?
> 
> Cliff
> 
> www.ProEV.com
--- End Message ---
--- Begin Message ---
When I said a few bucks I meant it.  Your prices are so reasonable for
repair.  Thank you for servicing your product so well.  Speaking of feeling
sorry, I have a box of a dozen or so mixed regs.   If you could work on some
and if the problems are simular I can finish them if you diagnose them if
you don't have the time to fix them all.  I like the old 1996 rev C Mark
ones.  When they are working they flash when connecting to the battery.  The
25w external load really works well.  I modified a few to blink at 10.1
instead of 9.6.  They are simpler than the MK IIs. Which makes me more
likely to work on them.   I really only need a few but with my reg busting
history I would like a few for a buffer.  I will leave the fuse holders on
and a few burnt fuses so you can see the  1/16 amp fuses with the little
resistor & coiled wire.  I thought this kind of fuse with a resistor might
be causing some trouble.  It does reduce the voltage to the sense by .02v
You can also see how I mounted your regs and if it isn't good maybe you can
advise me.  Thanks again.  Lawrence Rhodes....
----- Original Message -----
From: "Rich Rudman" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, October 30, 2002 9:29 AM
Subject: Re: The little Rudman that could.


> Lawrence Rhodes.  It's not the regs.
> > It's not the batteries that's the problm.  It's DUH.................I'll
bet
> > Rich has made a few bucks off DUH............
>
> No I  don't make much off of Ummmm "Troubles". I feel sorry for you all
> and take care of what I can fix, and hope all involved learned
> something.
>
>
> --
> Rich Rudman
> Manzanita Micro
> www.manzanitamicro.com
> 1-360-297-7383,Cell 1-360-620-6266
>
--- End Message ---
--- Begin Message ---
Cliff Rassweiler wrote:
> 
> So basically I can use one resistor and switch it on and off rapidly to keep
> the batteries below X volts. Which is basically the DC traction controller
> above controlled by voltage sensing?
> 
> Cliff

Don't do this. Rapid switching modulates battery voltage and inverter's
Pk controller deciding how much regen is allowed before max voltage is
reached will be confused - in your case there is no fixed max voltage,
just
2 kHz pulsating one. Pk controller will smooth is out and "average), 
but may try to modulate regen current with this 2 kHz freq, and you
won't like the outcome.

The voltage on the pack may change quickly, but should be smooth,
without PWM component in it. Leave this solution as absolutely
last resort.

Victor
--- End Message ---
--- Begin Message ---
Thomas,

We are building a car for closed circuit road racing. Some of us like to
turn <G>. Go to www.ProEV.com for more detail

Cliff

www.ProEV.com

----- Original Message -----
From: "Thomas Shay" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, October 30, 2002 3:18 PM
Subject: Re: Hardware for regen/dynamic braking set up?


> I'm puzzled about the reason to brake the car so hard.
> How much room is there to decelerate on a typical
> 1/4 mile drag strip?
>
--- End Message ---
--- Begin Message ---
Cliff Rassweiler wrote:
> 
>  > GET a Locomotive sized braking resistor, have it in  water, and
> > you can suck up about 180 Kw that way.
> 
> Good. Where do I find a locomotive size resistor? How much does it weigh?

Can you use a carbon pile type of dump load? Parallel IGBTs can
turn it on or off. Advantage is, you could design a hydraulic link
from the brake pedal to a cylinder similar to caliper wheel cylinders,
which will squeeze the pile as you brake, thus reducing its resistance,
thus keeping batteries from overvoltage and so allowing keeping
regenning.

Kind of feed back...

Just an idea.

Victor
--- End Message ---

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