# [EVDL] EV Controllers



## EVDL List (Jul 27, 2007)

[No message]


----------



## EVDL List (Jul 27, 2007)

Dave, this was a re-post of this link back in September 2006...

<snip>
...there is this 150V 400A open source project
http://vehiculeselectriques.free.fr/racingcontroller.html
that was posted by Philippe Borges 
under the thread RE: Building a Controller Yourself
<snip>

Mike,
Anchorage, Ak. 

> -----Original Message-----
> From: [email protected] [mailto:[email protected]]On
> Behalf Of [email protected]
> Sent: Sunday, August 19, 2007 5:03 PM
> To: [email protected]
> Subject: [EVDL] EV Controllers
> 
> 
> I've heard great things about the Zilla controllers but I understand they 
> are both very costly and there is a long waiting list for them. I am an 
> electronics engineer and would consider building my own controller. Are there 
> plans any where? Is there a schematic for the Zillas avaiable?
> 
> Thank you,
> 
> Dave Delman
> 1981 Electric DeLorean Project
> 
> 
> 
> ************************************** Get a sneak peek of the all-new AOL at 
> http://discover.aol.com/memed/aolcom30tour
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
> 

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

<<<< You can't get a schematic for the Zilla's because it belongs to the
designers and they will probably protect their intellectual property. They
make a living selling their controller, so they probably don't want to give
away the design. You could try asking them about it at their website,
though. [http://www.cafeelectric.com/]

I'm also looking at building my own controller. I was just going to design
it myself; I was thinking of basing it on a half-bridge circuit with
parallel'ed Mosfet's. IGBT's would be nice, but big ones are hundreds of
dollars each and small ones don't parallel well. >>>>

Otmar has spent so many thousands of hours perfecting the Zilla, 
you're getting your money's worth. Now if he could just keep up with 
demand...

DIY controller design always brings up Lee Hart's coffee can rule 
about dead silicon. You either know how to make one already or you buy 
- the learning curve could take longer than the Zilla's lead time and 
make *your* time worth less than a buck an hour (unless you consider 
it entertainment!)

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

cool, join the club.
there are a lot of naysayers here. like a crowd of high salary lawyers 
hiding in the closet that comes running out to discourage anyone daring 
to think it can be done relatively easy. the french project you were 
linked is in my opinion a mess simply because the documentation lacks 
concision. certainly not of the kiss school of thought.

although not a full car controller I'm much more enthusiastic about this 
'core' design: http://zeva.com.au/speedy/ by Ian Hooper (it works 
running a little old trolley car. he and I seem to agree more on 
design philosophy. it's based on a very easy to work with 
microcontroller and although the design doesn't have the functions 
needed for a full car controller (like current sensing so you dont fry 
stuff and motor rpm so you don't over rev it) it does have a basic 
design that should be possible to extend to a fully working simple and 
cheap design.
the microcontroller has enough input channels to handle 'everything' so 
the circuit complexity can be kept low. perhaps a few temperature 
sensors too.

I have been able to extract some experience from a sometimes unwilling 
crowd here  and I'm sure I forget some but I can mention a few insights.
(we should probably have a site with really good controller building 
pointers)

It seems that all commercial controllers use many small transistors in 
parallel instead of fewer larger ones, simple because the price is lower 
that way. the disadvantage seems to be that you have to watch for 
manufacturing differences in them so one doesn't try to take all the 
burden, then fry and take the others down with it causing a spectacular 
cascade failure (a common occurance among first timers from what I 
understand  I figure some math and some overkill might be able to 
handle that problem though.
The curtis controller uses some 30+ of a very common mosfet BUZ30A of 
form factor TO-220
http://www.ortodoxism.ro/datasheets/siemens/BUZ30A.pdf
(very small, not something you would expect could provide power for a car)

The zillas use a similar number of TO-247 form factor IGBTs which is 
also a small component. although several people on this list know which 
component it is they wont tell us. apparantly we don't share experience 
here. (they will give you an ocean of excuses why not. all wrong)

both controllers use a similar number of 'small' capacitors in parallel 
and surprisingly they seem to be greatly underspec'ed currentwise. when 
it comes down to it the batteries carry the bulk of the ripple current 
from the PWM paradigm and apparently it works out ok anyway. the curtis 
even have caps of a particularly poor quality from what I gather  with 
maybe a 40A total ripple current rating on a 550A controller.
Ian Hooper summed the parts on a curtis once and it has roughly 80$ 
worth of power electronics in it.

MOSFETs are faster but more expensive when it comes to higher voltage 
and power than IGBTs. I happen to think we have to move towards higher 
voltage because of significant advantages in efficiency, wire thickness 
etc but there is perhaps some advantage of ease in going with the lower 
curtis voltages because of batteries and typical motor designs. still a 
bit unclear on the motor theory.

A picture inside a curtis: http://www.df-cad.dk/web/ev/Curtis.jpg
and one of the Zilla2k http://www.df-cad.dk/web/ev/Zilla2kdiscovery.jpg

both controller seems to switch in the 15kHz region. I will be looking 
into switching at a much lower frequency because it costs energy each it 
switches and that is heat inside the transistors which you don't need. 
rough estimate that about half the heatloss in an IGBT at 15kHz is from 
the switching and the loss is linear with frequency. that's my 
impression so far at least.
The current rating on power transistors are usually higher than you can 
use them at. some say a factor 2. some say a factor 3. depends on 
cooling, frequency etc

there is more but that's what I could think of right now

oh from what I gather the current limit problem is most pronounced at 0 
rpm where the motor is largely a short circuit. especially if locked in 
place as the backemf only start to act like resistance when motor is 
turning (doing work, eating voltage and not just amps)

Lenz's law helps you out a little but the inductance in these motors are 
not high enough to save you for many microseconds so the current sensor 
has to be quick to save you from frying everything 

cool going with the DeLorean btw  I considered it myself but they are 
not cheap and not terribly well built so I figured it would be 
expensive. but done right it could be a real crowd pleaser  I'm 
thinking chrome the body work 

Dan







> [email protected] wrote:
> > I've heard great things about the Zilla controllers but I understand they
> > are both very costly and there is a long waiting list for them. I am an
> > electronics engineer and would consider building my own controller. Are there
> ...


----------



## EVDL List (Jul 27, 2007)

Was there a Discovery Channel program on EV conversions or something?


-----Original Message-----
and one of the Zilla2k http://www.df-cad.dk/web/ev/Zilla2kdiscovery.jpg

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

Hi EVerybody;

Waiting for a Frederikson controller, sounds good. Hope Dan can put it 
together, he makes it sound easy? He makes a few good points as I have scene 
My Curtis apart at Lee Hart's and the many tiny looking diodes and stuff 
look SO small to run a car. Lee pointed out that there ARE BIG diodes, 
IGBITS or whatEVer it takes to handle the hi power, over the counter stuff. 
The devil is the DETAILS! Protective circuits, we went over on the loooong 
drive with Lee to Fla and back. Had him trapped in the car. Ha Ha! He 
couldn't escape my "How to build a Controller" quaries. He sure made me 
appreciate what goes into them, you just don't throw stuff in a purple/green 
box and go! Taint that easy. Do-able, but you will be spending alota time 
designing protective circuits as EV controller stuff isn't mainstrean 
electronics like TV sets, washing machines. Ya looked at the NEW washers? 
All the electronic shit on THEM! Whatthehell is wrong with a cam timer that 
they have used since I was a kid, thousands of years ago?!FEH! Good folks 
like Otmar have DONE all the safety and control stuff, just for you.

Yeah! I know the shit's expensive, but price out building, say a V-8 
from scratch;cast the block, get the crank forged, pour yur own babbbit 
bearings,cast aluminum pistons. IF ya had to converyt say EV-1's to gas, and 
no cheating; hafta BUILD your own gas engine? Even a one lunger, it would be 
a long time and money thing.One lung 6" piston for more torque?No Briggs and 
Stratten here<g>!

Anyhow that's my input on controllers, for now. Start savin'

Bob
----- Original Message ----- 
From: "Dan Frederiksen" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, August 20, 2007 2:57 AM
Subject: Re: [EVDL] EV Controllers


> cool, join the club.
> there are a lot of naysayers here. like a crowd of high salary lawyers
> hiding in the closet that comes running out to discourage anyone daring
> to think it can be done relatively easy. the french project you were
> linked is in my opinion a mess simply because the documentation lacks
> concision. certainly not of the kiss school of thought.
>
> although not a full car controller I'm much more enthusiastic about this
> 'core' design: http://zeva.com.au/speedy/ by Ian Hooper (it works
> running a little old trolley car. he and I seem to agree more on
> design philosophy. it's based on a very easy to work with
> microcontroller and although the design doesn't have the functions
> needed for a full car controller (like current sensing so you dont fry
> stuff and motor rpm so you don't over rev it) it does have a basic
> design that should be possible to extend to a fully working simple and
> cheap design.
> the microcontroller has enough input channels to handle 'everything' so
> the circuit complexity can be kept low. perhaps a few temperature
> sensors too.
>
> I have been able to extract some experience from a sometimes unwilling
> crowd here  and I'm sure I forget some but I can mention a few insights.
> (we should probably have a site with really good controller building
> pointers)
>
> It seems that all commercial controllers use many small transistors in
> parallel instead of fewer larger ones, simple because the price is lower
> that way. the disadvantage seems to be that you have to watch for
> manufacturing differences in them so one doesn't try to take all the
> burden, then fry and take the others down with it causing a spectacular
> cascade failure (a common occurance among first timers from what I
> understand  I figure some math and some overkill might be able to
> handle that problem though.
> The curtis controller uses some 30+ of a very common mosfet BUZ30A of
> form factor TO-220
> http://www.ortodoxism.ro/datasheets/siemens/BUZ30A.pdf
> (very small, not something you would expect could provide power for a car)
>
> The zillas use a similar number of TO-247 form factor IGBTs which is
> also a small component. although several people on this list know which
> component it is they wont tell us. apparantly we don't share experience
> here. (they will give you an ocean of excuses why not. all wrong)
>
> both controllers use a similar number of 'small' capacitors in parallel
> and surprisingly they seem to be greatly underspec'ed currentwise. when
> it comes down to it the batteries carry the bulk of the ripple current
> from the PWM paradigm and apparently it works out ok anyway. the curtis
> even have caps of a particularly poor quality from what I gather  with
> maybe a 40A total ripple current rating on a 550A controller.
> Ian Hooper summed the parts on a curtis once and it has roughly 80$
> worth of power electronics in it.
>
> MOSFETs are faster but more expensive when it comes to higher voltage
> and power than IGBTs. I happen to think we have to move towards higher
> voltage because of significant advantages in efficiency, wire thickness
> etc but there is perhaps some advantage of ease in going with the lower
> curtis voltages because of batteries and typical motor designs. still a
> bit unclear on the motor theory.
>
> A picture inside a curtis: http://www.df-cad.dk/web/ev/Curtis.jpg
> and one of the Zilla2k http://www.df-cad.dk/web/ev/Zilla2kdiscovery.jpg
>
> both controller seems to switch in the 15kHz region. I will be looking
> into switching at a much lower frequency because it costs energy each it
> switches and that is heat inside the transistors which you don't need.
> rough estimate that about half the heatloss in an IGBT at 15kHz is from
> the switching and the loss is linear with frequency. that's my
> impression so far at least.
> The current rating on power transistors are usually higher than you can
> use them at. some say a factor 2. some say a factor 3. depends on
> cooling, frequency etc
>
> there is more but that's what I could think of right now
>
> oh from what I gather the current limit problem is most pronounced at 0
> rpm where the motor is largely a short circuit. especially if locked in
> place as the backemf only start to act like resistance when motor is
> turning (doing work, eating voltage and not just amps)
>
> Lenz's law helps you out a little but the inductance in these motors are
> not high enough to save you for many microseconds so the current sensor
> has to be quick to save you from frying everything 
>
> cool going with the DeLorean btw  I considered it myself but they are
> not cheap and not terribly well built so I figured it would be
> expensive. but done right it could be a real crowd pleaser  I'm
> thinking chrome the body work 
>
> Dan
>
>
>
>
>


> > [email protected] wrote:
> >> I've heard great things about the Zilla controllers but I understand they
> >> are both very costly and there is a long waiting list for them. I am an
> >> electronics engineer and would consider building my own controller. Are
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> [email protected] wrote:
> > DIY controller design always brings up Lee Hart's coffee can rule
> > about dead silicon. You either know how to make one already or you
> > buy - the learning curve could take longer than the Zilla's lead time
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> Greg Owen wrote:
> > As I understand it, controllers are complicated and expensive because
> > very extensive and, as you say, debugged logic needs to be rendered into
> > silicon.
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

> And each time you have a software bug, you just blew another can full of
> IGBT/MOSFET/Whatever parts.

The Zillas are completely worth every penny Otmar is asking for them,
and then some. I mean, nobody even MAKES DC controllers with his
specs, let alone with his reliability, tech support, and so on. Rather
than criticize him, people should be INVESTING in CafeElectric so he
can hire more people to MAKE more of em faster!

And come ON folks. He is not making himself rich with this. He is
making a living, to be sure, supporting himself, his entire family,
and his staff, but not rich. He'll be becoming rich when he has a
fully automated plant operating, making 1000 units per day and still
having a backorder.



--T

PS: Check out Gumstix computers: http://www.gumstix.com/

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> On 20 Aug 2007 at 9:50, John G. Lussmyer wrote:
> 
> > > Wouldn't it be easier to build a more generic 'sensor' end of the
> > > controller and pass info on to a generic PC where the actual decision
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> John G. Lussmyer wrote:
> >> Wouldn't it be easier to build a more generic 'sensor' end of the
> >> controller and pass info on to a generic PC where the actual decision
> >> logic is put into software? That lowers the cost and increases the
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

But you blow up parts while debugging and testing your code... I know,
I've done it. Stop the software debugger in the wrong place to check
some registers etc, and poof there goes a FET that's been on longer
than it should. Controller parts are gonna be *much* more expensive
than the cash drawer circuits I've blown up. I've designed both
circuits and microcode, and there's always been way more bugs in the
code than the hardware during the design process. There are orders of
magnitude more bugs if you're talking an OS, even a good open source
embedded one, than dedicated microcode.

> Seriously - I would think that hardware is just as likely to encounter
> 'bug' conditions as software of similar complexity (haven't I heard a
> bit about the raptor hardware being dicey for requirements?), and that a
> proper solution - hardware, software, or both - would involve fail-safes
> and pre-set safety limits. The difference is that software can be tuned
> more easily.
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

your on the wrong list serve for nice responses, but
seriously i know very little about the inside of a
controller and i agree that if a controller could be
made cheaper they would be and that controllers like
Zilla's are correctly priced

but:

can you build a simpler controller that is cheaper? 
the controllers i am familiar with regulate voltage
and amps based upon the logic of the controller, but
could you build a controller where you manually
control the amp and voltage? 



> --- Greg Owen <[email protected]> wrote:
> 
> > I appreciate any thoughts on the matter, so long as
> > they don't come wrapped around an e-brick 8).
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

You don't know anything about controller design yet you know they are 
priced right?
is that perhaps more a case of blind faith?

from what I understand a 'manual' control of amps would be at least as 
difficult. besides current limiting/sensing is not a costly thing in a 
controller from what I understand. more a case of having the expertise 
the design it to work right more than cost of the elements doing it. 
thus once designed has no significant adverse effect on production cost.

Dan



> dale henderson wrote:
> > you're on the wrong list serve for nice responses, but
> > seriously i know very little about the inside of a
> > controller and i agree that if a controller could be
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> On 20 Aug 2007 at 10:58, dale henderson wrote:
> 
> > can you build a simpler controller that is cheaper?
> 
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

Ignorance is fine as long as it isn't willful.
You don't actually have to make custom silicon. There is a category of 
components called microcontrollers.(not to be confused with the EV sense 
of the word controller) essentially a small cpu with a tiny bit of ram 
and flash ram built in. these can be programmed just like a pc although 
much simpler software of course.
it will then remember the software even in power failure and resume 
proper activity when power resumes. just as if it was custom hardware. 
the chip used in the previous trolley controller design is an AVR which 
is an 8bit cpu in the 286/amiga MHz range (up to 16Mhz iirc). it has 
several analog to digital sampling channels that can be used to monitor 
various signals as well as several PWM channels which can be used to 
pulse control the transistors for motor drive as well as the 12V DCDC 
supply if so desired. it costs 4$ and made by atmega. they do chips for 
automotive use too meaning they stand by the reliability. the zilla has 
such a chip as well although perhaps from a different brand. the curtis 
is analog which actually complicates the circuit design a lot.

Dan



> Greg Owen wrote:
> > Please pardon a stupid question...
> >
> > As I understand it, controllers are complicated and expensive because
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

yes there are and well priced, but even these have
programing of some sort that regulate the amps and
voltage applied. my question is can a simpler
[cheaper?] controller be built where the amps and
voltage are under manual control [might not call it a
controller anymore?]

if you hold the throttle at full power most
controllers [as i understand them] start off with high
amps and low voltage then [on their own] lower the
amps while increasing the voltage.




> --- David Roden <[email protected]> wrote:
> 
> > On 20 Aug 2007 at 10:58, dale henderson wrote:
> >
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

My first rides are always with a pair of jumper cables. Is this what you are after? It is definitely cheaper and the user is in control rather than a microprocessor and a bunch of expensive electronic parts.

You will have a hard time beating the price of an already engineered high amperage DC controller. Your only reasonable alternative on price alone is to find a bunch of appropriately sized surplus contactors and possibly diodes to build a contact or rectactor controller. Even this is hard to do for less money but if you get just the right hardware at a good price you can do it. 

Most of the cost of the controller is in the high current switching, not in the brains. 

damon
> Date: Mon, 20 Aug 2007 12:27:20 -0700> From: [email protected]> To: [email protected]> Subject: Re: [EVDL] EV controllers> > yes there are and well priced, but even these have> programing of some sort that regulate the amps and> voltage applied. my question is can a simpler> [cheaper?] controller be built where the amps and> voltage are under manual control [might not call it a> controller anymore?]
_________________________________________________________________
News, entertainment and everything you care about at Live.com. Get it now!
http://www.live.com/getstarted.aspx
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

>Seriously - I would think that hardware is just as likely to encounter 
>'bug' conditions as software of similar complexity (haven't I heard a 

No, for sure not. Software can't typically protect fast enough, even
if it works. On the indication of a short circuit or overcurrent at
these current levels, you have maybe only a couple of microseconds
to turn everything off. Many IGBT drivers these days include
desaturation detection so that if something shorts, it can be
turned off quickly. That is one of the main attractions of the
(admittedly overpriced) Powerex intelligent power modules. Desat
detection is included, and switching speeds are matched.

In my ICE ECM's, drivers are usually hardware protected, so that
even when a software bug leaves the output on, the output has
current limiting/shutdown 'just in case'. That happens frequently
during development. Once in production, obviously not often, but
you have to assume that the occasional crash will happen due to
ESD, EMI, power surge, or perhaps an occasional undetected
software bug.

Some MCU's include partial hardware protection in their motor
control PWM logic, so that an overcurrent (detected by a
comparator) will force a PWM-off condition. Considering that
this is pretty much standard equipment on motor control MCU's,
gate drivers, I think it is a pretty safe assumption that most
seasoned motor control designers use hardware protection
logic.

-Dale

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

my main goal is not to get a cheaper controller, but
one that i have more control over. i simply assumed
that a simpler [more manual] controller would be
cheaper/easier than an automatic controller. however
as i don't know the first thing about what goes inside
a controller i could be quite wrong.

what i want is a controller where i can manually
control both the amps and volts independent of each
other. and i was hoping that this would be something
easier to make than a 'standard' controller




> --- damon henry <[email protected]> wrote:
> 
> >
> > My first rides are always with a pair of jumper
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

I don't think having manual control over both current and voltage is realistic as they are tied together as part of the complete circuit. For instance, if you hold a specific voltage across a motor the load on the motor will determine the current. 

Alltrax controllers come with serveral different throttle profiles which allows you to vary the effect changing the throttle position produces. They also have different programmable ramp up and ramp down parameters.

damonDate: Mon, 20 Aug 2007 13:55:58 -0700From: [email protected]: [email protected]: Re: [EVDL] EV controllersmy main goal is not to get a cheaper controller, butone that i have more control over. i simply assumedthat a simpler [more manual] controller would becheaper/easier than an automatic controller. howeveras i don't know the first thing about what goes insidea controller i could be quite wrong.
_________________________________________________________________
Invite your mail contacts to join your friends list with Windows Live Spaces. It's easy!
http://spaces.live.com/spacesapi.aspx?wx_action=create&wx_url=/friends.aspx&mkt=en-us
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> Morgan LaMoore wrote: =
> 
> 
> > Yeah, it's not possible to control amps and volts =
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

>As for cost, 10 90A 100V FETs in parallel, several huge caps (about half a
>kiloJoule worth), and some big diodes will give me the power stage for
under
>$300 (I've priced it out). Add in another $300 for control, a case,
cooling,


I've done this kind of thing before. I don't want to be a naysayer, but
before you start with the paralleling aspect, get your controller to be
bulletproof on a single MOSFET. You'll probably blow up several of
them. You'll probably blow up a few sets of them when you start
hooking them in parallel, even after getting it solid with a single
one. This isn't pessimistic, it's realistic. Until you've sat at a
bench for hours trying to figure out why you just blew up a $300 set of
MOSFET's, with your ears still ringing from the explosion, you can't
really appreciate the power contained in those capacitors. Or that
you really should have made sure your 'scope was set to trigger on the
cause of the catastrophe that just happened. Be careful and good luck!!!
If you are halfways through an EE degree, try to get some help from
a power electronics prof, or better yet, someone who has built stuff
at these power levels before.

In a controller, and anywhere else, by the way, use an op-amp for amplifying
and a comparator for comparing, and don't ever, ever, ever, mix them up.
I'm guilty and managed to blow up maybe half a dozen IGBT's before realizing
that an LM2904 takes about 500 microseconds to compare, and an LM2903 takes
about 1 microsecond to do the same thing. A lot happens in 500 microseconds
in a battery charger or a controller... That was when I was about halfways
through an EE degree. Mostly I worked on a small (5kW) EV battery charger,
but I'd never design it that way now - it would not be reliable.

-Dale

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

>From: damon henry <[email protected]>
>Reply-To: Electric Vehicle Discussion List <[email protected]>
>To: Electric Vehicle Discussion List <[email protected]>
>Subject: Re: [EVDL] EV controllers
>Date: Mon, 20 Aug 2007 21:08:54 +0000
>
>
>I don't think having manual control over both current and voltage is 
>realistic as they are tied together as part of the complete circuit. For 
>instance, if you hold a specific voltage across a motor the load on the 
>motor will determine the current.

You've got the right idea - you can't control both voltage and current.

But, if you apply a specific voltage across a motor, it's the motor speed 
that will determine both the current and the torque output.

Phil Marino

_________________________________________________________________
A new home for Mom, no cleanup required. All starts here. 
http://www.reallivemoms.com?ocid=TXT_TAGHM&loc=us

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

You'd not use a PC for this task, but a microcontroller.
They do make microcontrollers rated for automotive environments. There
are very few supporting parts required around it. The system is far
simpler and far far FAR more reliable than a PC. Now it's not
problematic for the controller to talk to a PC, send it data about
current or whatever you want, or receive data from a PC. Or Palm Pilot.
Microcontrollers can be reprogrammed of course, usually bootloaders
will allow the PC to rewrite the controller's code through the
connection (a few seconds). Or just modify a few parameters without
rewriting everything.

Danny


----- Original Message -----
From: David Roden <[email protected]>
Date: Monday, August 20, 2007 12:13 pm
Subject: Re: [EVDL] EV controllers
To: Electric Vehicle Discussion List <[email protected]>



> > On 20 Aug 2007 at 9:50, John G. Lussmyer wrote:
> >
> > > > Wouldn't it be easier to build a more generic 'sensor' end of the
> > > > controller and pass info on to a generic PC where the actual
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

My ALLTRAX 7245 has a serial port which communicates
to a PC. I wonder if it has one of the
microcontrollers or PIC devices in it. It's why I
went with ALLTRAX rather than some of the other brands
like Curtis, etc. I liked the ability to change the
controller's parameters with the software interface
running on my laptop in the car, along with the
ability to monitor and save the live data while
driving the EV. I wish I had the brains to develop a
PC based GUI that would show the controller's data
output in a nice graphic display. I'll have to live
with my AllTRAX until I can get my EV license in
Oklahoma, in order to build a higher voltage EV. No
sense in buying a 1k or 2k zilla for a 78volt
system...... LOL




> --- [email protected] wrote:
> 
> > You'd not use a PC for this task, but a
> > microcontroller.
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

I just bought a 2400 Amp 1700 volt IGBT off eBay for $100. That should 
handle enough power for my DeLorean conversion even with the Flux Capacitor I 
have in the back!

Is there any group dedicated to high power controllers?



Thank you,

Dave Delman
1981 Electric DeLorean Project



************************************** Get a sneak peek of the all-new AOL at 
http://discover.aol.com/memed/aolcom30tour
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

>
> Regen is possible with series-wound motors. I believe a reason why the
> 'Zilla doesn't offer this feature is because Otmar's experiments with
> series motor regen suggest that it is hard on brushes/comms, especially at
> the sorts of voltages the 'Zilla users are likely to run.

Roger is correct. Otmar has an article on his website describing his
boost type regen. system using a Curtis controller. Worked well, but
later postings by Otmar described two month brush life due to the lack of
commutating/compensating poles in the small frame motors used in hobbyist
EV's.

Curtis
> offers/offered a regen controller (1221R) for series motors, and Otmar
> once published instructions on how to modify a standard Curtis for regen
> operation (though he advised against doing so based on his experiences
> with the setup). Not sure if these instructions are available on the Caf=
=E9
> Electric site; I think they may originally have appeared as an article in
> Home Power?

The Curtis 1221R was never available in the US, believe it only went up to
120 volt systems and seems not available presently.
>
> A "simple" regen scheme I saw described in a paper some time back involved
> assumed a pack composed of 6V floodies and used a couple of contactors, a
> beefy diode, and a power resistor (a length of allthread with washer
> "fins") to connect one 6V battery to the motor field for excitation and to
> parallel the two halves of the pack during regen to allow regen to lower
> speeds/at lower motor RPM.

This was probably Gary Jackson of "Little Guy Racing" in Southern
California who used to race Fred Schilling's VW Rabbit with a Prestolite
motor and Russco Controller. Gary wrote a book on his regen. system that
Ken Koch at KTA sells.

The Russco Orange Juicer I had a similar regen. system around 1985. =

Divide the 84 volt system with a series/parallel contactor setup and apply
2 volts to the field with a single Trojan cell. Worked like a champ. =

Russco's present EV, Orange Juicer II, a VW bug, will use a similar regen.
system but instead of the two volt cell, will use a DC-DC converter to
provide the field excitation of 2 volts at 200 amps. Updated information,
including pictures of the inside of the new 600 amp Russco controller and
the Russco motor field converter will be posted on the Russco website in
the next 30 days. Information will be under "Russco's EV," sub Russco
Motor Controller and sub Russco Regenerative Braking.

Russ Kaufmann

RUSSCO Engineering

http://www.russcoev.com

The Other PFC Charger With Built In GFCI.


_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

EV license?? what's that?

Dan

Michael Barkley write:
> My ALLTRAX 7245 has a serial port which communicates
> to a PC. I wonder if it has one of the
> microcontrollers or PIC devices in it. It's why I
> went with ALLTRAX rather than some of the other brands
> like Curtis, etc. I liked the ability to change the
> controller's parameters with the software interface
> running on my laptop in the car, along with the
> ability to monitor and save the live data while
> driving the EV. I wish I had the brains to develop a
> PC based GUI that would show the controller's data
> output in a nice graphic display. I'll have to live
> with my AllTRAX until I can get my EV license in
> Oklahoma, in order to build a higher voltage EV. No
> sense in buying a 1k or 2k zilla for a 78volt
> system...... LOL
>
>


> > --- [email protected] wrote:
> >
> >
> >> You'd not use a PC for this task, but a
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> On 20 Aug 2007 at 12:27, dale henderson wrote:
> 
> > my question is can a simpler
> > [cheaper?] controller be built where the amps and
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

If you want to try a low voltage controller why not try this basic design
http://zeva.com.au/speedy/
it's working afaik and extendable because of the microcontroller

Dan



> Morgan LaMoore wrote:
> > Roger,
> >
> > OK, I guess you can control volts and amps at the same time. I'd call that
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

> more soon.
>
> As for cost, 10 90A 100V FETs in parallel, several huge caps (about half a
> kiloJoule worth), and some big diodes will give me the power stage for
> uunder $300 (I've priced it out).

What is the ESR for those caps? at that price I can't imagine that it
will be good enough for a 72V 250A controller (about what those FETs are
good for)


> Add in another $300 for control, a case,

not to mention the extra cost for replacing the silicon a few times as you
(hopefully) learn from your mistakes. It doesn't take many mistakes to
push the price over the $700 it would cost to buy a 72v 400A controller.

If you reaaly want the learning expierence, I'd recommend starting samller
where the mistakes are cheaper, say 36V @ 50A. that's enough power for
a fun scooter / ebike

> cooling,
> and misc. costs, and I should have a 600A continuous (higher peak)
> controller for a 72V system for about $600.

actually you usually need to derate the silicon to aound 1/3 - 1/4 in
order for it to survive long enough to detect and correct for and over
current situation.

> I guess if DC series-wound regen were
> possible,
> the Zilla would already have it.

regen with a series motor is possible, there are a couple different problems.

one problem is the brush angle. Unless you have one of the rare series
motors that have interpoles, the brushes need to be advanced for normal
operation to avoid arcing, but they need to be retarded for regen.
So series motors set up for regen usualy have the brushes at the neutral
position which isn't particularly good for either normal or regen
operation. Several folks have fried their motors with regen setups.

Another problem is that series regen usually isn't very efficient. It
slows you down, but doesn't put much juice back in the pack.

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> Morgan LaMoore wrote:
> 
> > OK, I guess you can control volts and amps at the same time.
> > I'd call that controlling volts or amps depending on which
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> Morgan LaMoore wrote:
> 
> > Sorry if I sound defensive, but I can't have anyone
> > thinking I'd try to break Ohm's law! :-D
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

What is the purpose of the large, low ESR capacitors?



Thank you,

Dave Delman
1981 Electric DeLorean Project



************************************** Get a sneak peek of the all-new AOL at 
http://discover.aol.com/memed/aolcom30tour
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

Well look at all the numbers surrounding this situation though. You've 
got 150A ripple handled by the caps. So 50% of the time you've got 150A 
flowing into them, 50% of the time 150A out. Average absolute val of 
current is 150A. I2R=50W of heat originating in those caps. That's a 
signficant amount of heat. 20 in parallel, 2.5W per cap, sounds 
reasonable if they're big caps and you've got some sense of cooling. 
It's a rough situation though because most cap construction- unlike 
transistors and power resistors- has a limited thermal conductivity to 
the air combined with a lack of tolerance for high internal temps. The 
outer covering is usually plastic which holds in heat and will melt if 
it heats up. The cap's electrolyte inside will cook well below the 
Tjmax of a typical transistor or the "magic smoke" temp of a power resistor.

Also problematic is the ESR of a cap is not consistent through the life 
of the product. Say that ESR creeps up to 4mOhm later as the caps age a 
bit ahead of schedule due to high current and high temps, the I2R power 
goes up to 90W, operating temps increase to an unreasonable level. 
Hard to get guarantees of long term performance. Acutally what 
typically happens is when the ESR increases the caps simply absorb and 
release much less of the ripple and the battery starts taking all the 
ripple.

Just pointing out the difficulties in these cap banks. Your solution 
sounds like one of the better ones!

Danny



> Morgan LaMoore wrote:
> 
> >As an example, United Chemi-Con has some caps that are 5600 uF 0.044 Ohm
> >each. 20 in parallel costs $150 and gives me 112 mF at 2.2 mOhm. For some
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

It's even a lot more than the typical bank can handle it seems
for some reason it's accepted to let the batteries carry the bulk of the 
ripple current, not the caps
as much as 90%

Dan



> Morgan LaMoore wrote:
> > Dave,
> >
> > The caps act as a huge supply bypass, providing the ripple current for the
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

There's no mystery to the reason. Caps are big, very expensive, and of 
limited long-term reliability under currents of this magnitude.

Danny



> Dan Frederiksen wrote:
> 
> >It's even a lot more than the typical bank can handle it seems
> >for some reason it's accepted to let the batteries carry the bulk of the
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

well, considering the power electronics in a typical curtis is around 
80$ in total (at 1000 unit prices) having more caps should easily be doable
they are not 'very expensive'. they might well be less than a dollar a 
piece so having a few hundreds of those is doable but I guess most don't 
care to have to wire that many and house them either.

Dan



> Danny Miller wrote:
> > There's no mystery to the reason. Caps are big, very expensive, and of
> > limited long-term reliability under currents of this magnitude.
> >
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

try to do the math on that, my hunch is that unless those lines are very 
long and thin that the load difference wont be significant
try not to be a naysayer

Dan




> Morgan LaMoore wrote:
> > Plus, there's another problem I've been thinking of:
> >
> > If you take a ton of capacitors, wire them together, and treat them as
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

looking at the diagram for a curtis I don't see any smaller and better 
caps, only the main array of identical caps. where are you getting this 
information?

Dan



> Bill Dube wrote:
> > Completely incorrect.
> >
> > Inside the controller, there are smaller, but "better", blocking caps
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

Again don't neglect this issue of ripple performance in the capacitors 
themselves. Cheap caps typically don't have good ripple performance.
We're looking at the stated ripple rating, the ESR, and the temp rating- 
since the caps can get quite hot running at high currents yet they 
typically don't tolerate high operating temps.

The ESR is the killer. Here's the catch- capacitors only charge or 
discharge with a change in voltage. We're trying to make a situation 
where the voltage doesn't change. If the batt/cap voltage changes much, 
then the batt will be picking up the ripple instead of the cap. We've 
got to overwhelm the battery's low ESR with an even lower cap ESR. It's 
not only hard to get ESRs that low, but it's a fleeting thing- cap ESR 
increased with high current and high temp operation, and it's only got 
to creep up a little to lose those hard-won design gains.

Really it makes a lot of sense to use a massive inductor to smooth out 
battery current. Inductors operate directly on changes in current, 
rather than these marginal gains as you go with larger and larger caps.

Danny



> Morgan LaMoore wrote:
> 
> >Plus, there's another problem I've been thinking of:
> >
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> Danny Miller wrote:
> > Again don't neglect this issue of ripple performance in the capacitors
> > themselves. Cheap caps typically don't have good ripple performance.
> >
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*


----------



## EVDL List (Jul 27, 2007)

> Dave Delman wrote:
> > I am an electronics engineer and would consider building my own
> > controller. Are there plans any where? Is there a schematic for
> > the Zillas avaiable?
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> Morgan LaMoore wrote:
> > I was also thinking about a massive inductor. With the currents we're
> > dealing with, we don't need much battery inductance to make our caps
> > deal with the ripple. An inductance of 1uH at 15kHz with a 2V ripple
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

I just replaced the capacitors in a 10-year-old Curtis 1221. They
weren't "bad" per se; just old. I have an ESR meter. The old caps were
Nichicon VX series, 220uF 160vdc. Their ESRs measured 0.06 to 0.13 ohms.

The new parts I used are Panasonic FA series, 220uF 200vdc. They
measured 0.01 to 0.02 ohms. My meter only resolves to 0.01 ohms, so this
is low enough to be lost in the noise.

If anyone doesn't believe low ESR is important in a controller, I'd be
glad to sell you the old Nichicon parts for just the cost of shipping.
They will work; but you will have higher voltage spikes on your
switching transistors and the batteries will see more ripple current.



> Danny Miller wrote:
> > The ESR is the killer... We've got to overwhelm the battery's low
> > ESR with an even lower cap ESR.
> > Really it makes a lot of sense to use a massive inductor to smooth out
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> Lee Hart wrote:
> > The new parts I used are Panasonic FA series, 220uF 200vdc.
> according to panasonic's site the FA series was dicontinued in 2000 and
> only goes to 63v. so what's the dealio : ) does it say FA series on
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

Lee,


How many of those caps are in a Curtis? 

I just replaced the capacitors in a 10-year-old Curtis 1221. They
weren't "bad" per se; just old. I have an ESR meter. The old caps were
Nichicon VX series, 220uF 160vdc. Their ESRs measured 0.06 to 0.13 ohms.





Thank you,

Dave Delman
1981 Electric DeLorean Project



************************************** Get a sneak peek of the all-new AOL at 
http://discover.aol.com/memed/aolcom30tour
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*

----- Original Message ----- 
From: <[email protected]>
To: <[email protected]>
Sent: Saturday, August 25, 2007 11:53 AM
Subject: Re: [EVDL] EV controllers


>
>
> Lee,
>
>
> How many of those caps are in a Curtis?
>
> I just replaced the capacitors in a 10-year-old Curtis 1221. They
> weren't "bad" per se; just old. I have an ESR meter. The old caps were
> Nichicon VX series, 220uF 160vdc. Their ESRs measured 0.06 to 0.13 ohms.
> Hi Lee;

Dems wouldn't be in MY Curtis controller? Rebuilding it to better than 
spec?

Bob
>
>
>
>
> Thank you,
>
> Dave Delman
> 1981 Electric DeLorean Project
>
>
>
> ************************************** Get a sneak peek of the all-new AOL 
> at
> http://discover.aol.com/memed/aolcom30tour
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
>
> -- 
> Internal Virus Database is out-of-date.
> Checked by AVG Free Edition.
> Version: 7.5.476 / Virus Database: 269.11.15/949 - Release Date: 8/12/2007 
> 11:03 AM
>
> 

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> [email protected] wrote:
> > Lee, How many of those caps are in a Curtis?
> 
> 32.
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] EV controllers*



> Bob Rice wrote:
> > Dems wouldn't be in MY Curtis controller? Rebuilding it to better than
> > spec?
> 
> ...


----------

