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Today's Topics:
1. Re: Absolute max input voltage of the Z1K-HV? (Andrew Letton)
2. Re: article: Mitsubishi i MiEV Sport - brutally fast electric
sports car prototype (Glenn Saunders)
3. Re: article: Mitsubishi i MiEV Sport - brutally fastelectric
sports car prototype (Harris, Lawrence)
4. Re: zivan Instructions on ebay - scam or real?
([EMAIL PROTECTED])
5. Re: Vectrix braking flaw? (Charles Whalen)
6. Re: Video pictures, write-up (Ted Sanders)
7. Re: Vectrix braking flaw? (Glenn Saunders)
8. Re: Vectrix braking flaw? (Roger Stockton)
----------------------------------------------------------------------
Message: 1
Date: Thu, 15 Nov 2007 11:35:45 -0800
From: Andrew Letton <[EMAIL PROTECTED]>
Subject: Re: [EVDL] Absolute max input voltage of the Z1K-HV?
To: [EMAIL PROTECTED]
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Here's a message that Ot asked me to forward to the list, since he's not
subscribed these days.
cheers,
Andrew
-------- Original Message --------
Subject: Re: [Fwd: Re: [EVDL] Absolute max input voltage of the Z1K-HV?]
Date: Wed, 14 Nov 2007 22:17:46 -0800
From: Otmar Ebenhoech <[EMAIL PROTECTED]>
To: Andrew Letton <[EMAIL PROTECTED]>
References: <[EMAIL PROTECTED]>
Hi Andrew, Thanks for the heads up!
I sure would appreciate it if you could post the following to the list:
Hello All,
Yes, I've made a mistake here.
Years ago when I designed the EHV model of the Zilla series of
controllers I intended them to be able to handle 400V on the input at
full load and to reduce load as they approached the cut off voltage
of 429 Volts. They still will try to do that, but the question is
will they survive? In truth the spec was based on design, but rarely
tested.
I've never had a Zilla fail in service due to excessive voltage, and
who knows how high people have taken them? :) I load each EHV
controller to full output current at about 375V while watching a
number of critical parameters in testing. This is all the capability
I have at the shop, and I feel plenty nervous doing that.
It also seems that no matter how high I spec a controller, Mr Berube
will always lead the way at pushing the voltage higher to see if it
blows up. :)
For the first few years Berube was the only one I knew of running the
unit at 348V and high voltage vehicles were very rare. Eventually I
heard he was running it at 360V nominal, and then Wayland decided to
follow suit. They assured me that they were bleeding the pack well
off surface charge before starting them up. We had no troubles, but
also only a very small pool of samples.
Recently I've had a problem with a few gate driver DC-DC's failing
causing a "Quiet Zilla". More details about it are in my production
blog here:
http://www.cafeelectric.com/blog/?p=23
It's happening in high voltage units and mostly units that have had
motor fireball incidents or other ground faults. The actual source of
the probem has been a bit of a mystery. Early on in the process of
diagnosing the problem I took the main power supply (that powers the
DC-DC converters on the gate drive) to 400V and above. What I found
was as expected that at light internal loads (not driving) the main
supply output voltage would float upwards when the input was over
375V. The design has a zener diode to limit it and slightly increase
the load in those cases. I was nervous since the tolerance on the
zener came pretty close to the maximum rated input voltage for the
DC-DC converters. Additionally, the failure mode of the DC to DC
converters was mimicking excessive input voltage. So with that in
mind, and since I could only test to 375V I told people that I really
didn't want them exceeding 375 volts on the input.
About a week ago with a great tip from Lee Hart, I found that the
real "Quiet Zilla" problem seems to be the inability of these small
integrated DC-DC's to meet the spec sheet values of isolation and
that this is blowing the input stages. As a result I'm in the middle
of designing a replacement for that design and hope to have a
solution soon. Additionally early on I redesigned the main power
supply with a newer control chip that can keep the supply from
creeping up at high voltage. These should all be tested and in
production early next year. Does this mean that I will lift the 375V
recommendation on the EHV Zillas? I'm not sure. I still get awfully
nervous at EHV testing but I agree that it would be nice to run the
full 400V+ that they were designed to handle. We'll see how
adventurous I feel when I get through with this.
In the meantime, I plan to drop the rating in the manual since that
is misleading and doesn't agree with my current comfort level. I am
really sorry I did not do that earlier. My only poor excuse is that
any change to the manual requires a lot of busywork converting it
into HTML and pdf for people to get web access.
Matt Graham, your non-start is not intentional by the Hairball. This
is the first I remember hearing of such a problem. I see that you say
you talked to me about it, I may have recommended a EHV Hairball, you
certainly don't need a EHV Zilla. You have a -4 Hairball which
historically had no trouble starting at 325V, but maybe in hot
weather it is a problem? You could try holding the start key extra
long (like 40 seconds) (that's how I test EHV controllers with a -4
Hairball in my car at 375V) or if you send the Hairball in to the
shop, I'll make it a -6 (EHV) no charge (plus update the code) and
that should solve the problem.
Just for accuracy, the TI part has the isolation problem, not a creep
up in voltage problem. The creeping voltage is in the main wide input
range supply that uses a Topswitch. Changing to the new Topswitch GX
model allows frequency reduction and pulse skipping which removes the
float at minimum duty cycle. Back when I designed this, the Topswitch
was new and didn't have those features.
I hope this clears some things up,
-Otmar-
914 EV, California Poppy,
http://evcl.com/914/
Insight EV,
http://www.cafeelectric.com/Insight/
http://www.CafeElectric.com/
The Zilla factory.
>Steven Ciciora wrote:
>
>>For what it's worth, when I was in Oregon at PIR, Otmar told
>>me that the absolute max he currently recommends for the EHV
>>version is 374 volts
>
>Otmar really ought to update his manual/specs then, as what he
>continues to advertise is 348V nominal, and 400V max "fully loaded".
>
>374V is just barely enough to accomodate a 348V pack that has
>relaxed to about 2.15V/cell off charge. (12.9V/12V module).
>
>>Otmar said that the Zilla will limit duty cycle
>>above 374V, and above this voltage is pushing the limits of
>>the DC-DC converter on the gate driver board. The TI part
>>(the DC-DC converter) has a minimum pulse width that it can't
>>make any shorter, and above 374V, it can't regulate the
>>output and it starts drifting up. Yet another reason why we
>>stay at 374V on an EHV Zilla.
>
>This makes Otmar's recommendation of 400V max fully loaded seem really odd...
>
>>--- Matt Graham <[EMAIL PROTECTED]> wrote:
>>
>>> My experience is that, as advertised, 300V nominal is the
>>> maximum you can use with the -HV model. I've been running
>>> the Z2K-HV at 300V in Joule Injected for a couple years now.
>>> The maximum voltage is typically on the order of 325V or so
>>> when starting out, and at this voltage, I've never had any
>>> problem.
>>>
>>> However, there have been times when the voltage has been
>>> higher on startup after a good equalization charge. At these
>>> times, I've noticed that the Hairball will not engage the
>>> main contactor initially.
>
>This really makes it seem like Otmar's published specs may be
>optimistic. It doesn't seem quite right to advertise the HV model
>as capable of 72-300V nominal battery voltage if it cannot actually
>tolerate the voltage of a 300V nominal pack just off charge...
>
>I'm a bit surprised and disappointed that the Zilla's voltage specs
>would be 'overstated' in this way. The 'Zilla has such an
>outstanding reputation that I would have expected it to actually be
>happy with voltages right up to the stated max or a bit beyond,
>rather than being at the hairy edge of not operating at all even
>when operated within the upper limit of its spec. After all, the
>Zilla has no competition, so there is no reason to spec it
>optimistically: if the real safe upper limit of the HV is 288V
>nominal (so that it is guaranteed to work no matter how fresh off
>charge the pack is), just say so. Likewise, if the -EHV is really
>only going to work with a fully charged 336V pack, just say so, it
>isn't like the customers will go elsewhere! ;^>
>
>Steve, please share with the list what you find out from Otmar
>(better still, suggest to Otmar that he update the 'Zilla manual
>with the clarification so that the next time it comes up the answer
>is readily available 'from the horse's own mouth', as it were.) ;^>
>
>Cheers,
>
>Roger.
--
------------------------------
Message: 2
Date: Thu, 15 Nov 2007 11:41:52 -0800 (PST)
From: Glenn Saunders <[EMAIL PROTECTED]>
Subject: Re: [EVDL] article: Mitsubishi i MiEV Sport - brutally fast
electric sports car prototype
To: Electric Vehicle Discussion List <ev@lists.sjsu.edu>
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset=us-ascii
It means some dodo over at Mitsubishi believes in perpetual motion machines.
----- Original Message ----
Same reaction here.
What in heck does this mean?
"....and a fan inside the front grill that generates electricity from
the rush of air flow, both of which put energy back into the battery,
just as the vehicle's regenerative braking also does."
------------------------------
Message: 3
Date: Thu, 15 Nov 2007 11:39:43 -0800
From: "Harris, Lawrence" <[EMAIL PROTECTED]>
Subject: Re: [EVDL] article: Mitsubishi i MiEV Sport - brutally
fastelectric sports car prototype
To: "Electric Vehicle Discussion List" <ev@lists.sjsu.edu>
Message-ID:
<[EMAIL PROTECTED]>
Content-Type: text/plain; charset="us-ascii"
Seems silly but if you only energize the fan motor/generator when you
want to slow down then it would just add a drag effect and put a few
electrons back in the batteries as a side effect. Might even give you
the feeling of compression braking at higher speeds. Add variable pitch
to the blades and you might even get some serious drag control across a
fairly large speed range. On a prototype car this would not be much
different in spirit than the photo cells on the roof.
Lawrence
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Tehben Dean
Sent: Thursday, November 15, 2007 11:21 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] article: Mitsubishi i MiEV Sport - brutally
fastelectric sports car prototype
Same reaction here.
What in heck does this mean?
"....and a fan inside the front grill that generates electricity from
the rush of air flow, both of which put energy back into the battery,
just as the vehicle's regenerative braking also does."
On Oct 25, 2007 6:52 PM, Hunter Cook <[EMAIL PROTECTED]> wrote:
> Looks interesting. Most of it is pretty cool...I still don't know how
to
> feel about hub motors (are they sprung?), but this bit is the only one
> that really got my eyebrows raised:
>
> "Someone at Mitsubishi has been really thinking outside the square in
> getting the most out of the vehicle because the car has several
features
> we haven't seen before, including an auxiliary photovoltaic unit built
> into the roof, and a fan inside the front grill that generates
> electricity from the rush of air flow, both of which put energy back
> into the battery, just as the vehicle's regenerative braking also
does."
>
> A FAN!? Please, tell me the reporter made that up as a joke.
>
> Hunter
>
> On Thu, 2007-10-25 at 23:09 +0000, Paul Wujek wrote:
> > Details and pictures of the prototype:
> >
> >
http://www.transport20.com/electric-vehicle/mitsubishi-i-miev-sport-brut
ally-fast-electric-sports-car-prototype/
> >
>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
--
Tehben
'90 Toyota 4x4 Pickup
'hElix EV'
Website: www.helixev.com
evalbum: http://www.austinev.org/evalbum/1225
_______________________________________________
For subscription options, see
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------------------------------
Message: 4
Date: Thu, 15 Nov 2007 14:44:10 -0500
From: [EMAIL PROTECTED]
Subject: Re: [EVDL] zivan Instructions on ebay - scam or real?
To: ev@lists.sjsu.edu
Message-ID:
<[EMAIL PROTECTED]>
Content-Type: text/plain; charset=us-ascii
with the zivan It's harder to fry a flooded battery.
sure you can boil anything to desert dry, but with flooded, the overcharged
vents more and you just add to it more water.
sound right?
On another car with sealed lead acid;
even with the powercheq's the zivan on the one night that it didn't shut
off, fried some of the batteries.
A timer would have been helpful. $30 timer now or $4,000 later?
hmmm
------------------------------
Message: 5
Date: Thu, 15 Nov 2007 14:34:50 -0500
From: "Charles Whalen" <[EMAIL PROTECTED]>
Subject: Re: [EVDL] Vectrix braking flaw?
To: <[EMAIL PROTECTED]>, "Electric Vehicle Discussion
List" <ev@lists.sjsu.edu>
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset="iso-8859-1"
Given that you've been riding longer than I have, 44 years in your case, I
wouldn't say it's a lack of experience. Rather, I would say that this is a
good example of how what is most logical, natural, intuitive, and
ergonomic to the brain, reflexes, and eye-hand-foot-brain coordination is
really highly subjective and personal. This reminds me of the very
passionate debates that come up a few times a year on the RAV4-EV discussion
list and go on and on ad-infinitum and ad-nauseum about the best
implementation of regen braking (in a car) and whether it's: a) on a
handlever accessed by your right hand (e.g. as on the gearshift lever),
b) seamlessly blended with the friction brakes on the brake pedal (on the
floor), c) blended into the accelerator pedal, in the top half of its
travel, when backing off (a la Solectria and AC Propulsion), d) two brake
pedals (on the floor), one for friction braking and the other (where the
clutch would be) for regen braking, e) various combinations of the above,
etc., etc. The wide range of opinions and how strongly they are held is
indicative of how personal and subjective this is.
I can see your point, from your perspective, about how much more logical,
natural, and intuitive it would be to have all of the rear-wheel braking
functions (both regen and friction) together on the right handlebar and the
front-wheel braking function (friction) on the left handlebar. The only
thing I can suggest is that you either build your own electric motorcycle or
have a good custom electric motorcycle builder build one for you, in which
case you or the builder can build the bike exactly to your specs and
preferred ergonomic functionality, including putting the rear-wheel braking
function(s) on the right and the front-wheel braking function on the left.
I can recommend an excellent custom motorcycle builder, my fellow Florida
EAA member Jeff Patterson of Patterson Cycles (www.pattersoncycles.com) in
Jupiter, Florida. I have ridden his electric motorcycles and they are
absolutely fabulous! I hate to admit that Jeff's bikes are more fun than
the Vectrix, but it's the same difference between my RAV4-EV and Steve
Clunn's screamers. The raw power and breathtaking exhilaration that you get
from a Clunn screamer or a Patterson e-motorcycle is something that you
could just never get from the more efficient, refined production vehicles
like the RAV4-EV and Vectrix.
Good luck with whatever you decide to do.
Charles Whalen
Delray Beach, FL
----- Original Message -----
From: "rubberlegs" <[EMAIL PROTECTED]>
To: "Charles Whalen" <[EMAIL PROTECTED]>; "Electric Vehicle Discussion
List" <ev@lists.sjsu.edu>
Sent: Thursday, November 15, 2007 1:55 PM
Subject: Re: [EVDL] Vectrix braking flaw?
You are more skilled than I. I've only been riding
since I was 16 (I will be 60 next month). I still
think that it makes no sense to have the braking for
both the front and rear wheel controlled by the same
(right) hand. It would be much better for brain
function and reflex to have the right hand control the
rear wheel braking only and the left hand to control
front wheel braking only. But those of you on this
list seem to believe the problem simply lies with my
lack of experience. Thanks for your input.
--- Charles Whalen <[EMAIL PROTECTED]> wrote:
> I have had to stop from high speeds in very short
> distances a number of
> times, including in some racing situations on the
> track. I apply: 1) full
> regen, 2) right-hand front brake, and 3) left-hand
> rear brake, all three
> simultaneously, the combination of which I find very
> effective, and don't
> have a problem with this. But as someone else
> mentioned, you need to
> practice this on a regular basis so that it becomes
> second nature and
> instinctive when you need it in an emergency. In
> particular, I find that
> the combination of (1) and (2) is a very easy and
> natural movement,
> egononically speaking. One has to let up on the
> throttle anyway as you're
> going for the right-hand front brake lever (on all
> motorcycles, including
> the Vectrix). So I just continue that movement all
> the way to the top
> travel of the throttle (which is max regen) with my
> right thumb and palm of
> my right hand as I'm reaching for the right-hand
> front brake lever with my
> four other fingers (and simultaneously reaching for
> the left-hand rear brake
> lever with my left hand). It's a continuous motion
> that all happens in a
> fraction of a second. Maybe it's because I've
> ridden motorcycles for over
> 30 years and flown airplanes for 15 that I am
> accustomed to having all four
> limbs doing between 4 and 8 separate tasks
> simultaneously in a coordinated
> fashion (sometimes with a given hand or foot doing
> two tasks at the same
> time), so this coordinated braking situation with
> the Vectrix is not a
> problem for me. (Of course on the Vectrix my feet
> are unemployed and
> bored.) But yes, you should definitely practice
> this from time to time.
> Anyway, I'm sorry to hear about your spill and hope
> you and the bike are OK.
>
> Charles Whalen
> Delray Beach, FL
>
>
> ----- Original Message -----
> From: "fortywattblub"
> <[EMAIL PROTECTED]>
> To: <ev@lists.sjsu.edu>
> Sent: Wednesday, November 14, 2007 3:30 PM
> Subject: [EVDL] Vectrix braking flaw?
>
> > I went down on my Vectrix (could have been killed)
> because the rear wheel
> > locked up in an emergency situation. It seems to
> me that they should have
> > the front hand brake on the left side. Vectrix
> encourages riders to use
> > the regen braking whenever possible. However, when
> one gets in the habit
> > of using the regen on the throttle the tendency in
> an emergency is to hit
> > the regen and the left hand brake which is also
> the rear wheel???causing the
> > rear to lock up and fishtail. I have decided to
> stop using the regen
> > because I want to go for the front brake
> automatically in an emergency.
> > Is there any good reason to use the regen braking
> other than to get a
> > little charge? It seems to create a lot of torque
> on the motor and if one
> > isn't concerned about the slight recharge perhaps
> not using it will save
> > some wear on the motor. I'm just speculating on
> this. Also, is there a
> > vehicle code that says the the left side hand
> brake must be for the rear
> > wheel? I want to reverse my handbrakes, but until
> then I will just stop
> > using the regen to avoid training myself away from
> the front (right) hand
> > brake. (It's very awkward to reverse throttle for
> regen and pull the right
> > hand brake simultaneously.)
> > --
> > View this message in context:
> >
>
http://www.nabble.com/Vectrix-braking-flaw--tf4801786s25542.html#a13738768
> > Sent from the Electric Vehicle Discussion List
> mailing list archive at
> > Nabble.com.
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
------------------------------
Message: 6
Date: Thu, 15 Nov 2007 13:51:13 -0600
From: Ted Sanders <[EMAIL PROTECTED]>
Subject: Re: [EVDL] Video pictures, write-up
To: Electric Vehicle Discussion List <ev@lists.sjsu.edu>
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset="iso-8859-1"
Why doesnt everyone just ingore Dan?
Beano -- 1981 Ford Escort EV
EValbum 1010Ted Sanders
> Date: Thu, 15 Nov 2007 11:54:51 -0600> From: [EMAIL PROTECTED]> To:
> ev@lists.sjsu.edu> Subject: Re: [EVDL] Video pictures, write-up> > On Nov 15,
> 2007 9:57 AM, Dan Frederiksen <[EMAIL PROTECTED]> wrote:> > no, I'm talking
> about the first youtube clip Bill offered, not the one> > after which he
> specificaly describes as a cellphone camera.> > the first one is overexposed.
> youtube doesn't do that. either the camera> > did or it was done after
> recording. if a DV camera was used why wouldn't> > he just say so after I
> suggested he use a DV camera rather than the> > 'show me the money'> >> >
> Dan> > Because he didn't do the filming. The video was from some random>
> audience member with a cell phone. There is no way Bill was there> being a
> one-man pit crew *and* video taping everything. If Bill bought> a nice video
> camera, it wouldn't help, because he wouldn't have time> to use it. (Unless
> he loaned it to some random audience member to film> for him and trusted them
> to not ta!
ke it.)> > -Morgan LaMoore> > _______________________________________________>
For subscription options, see> http://lists.sjsu.edu/mailman/listinfo/ev
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------------------------------
Message: 7
Date: Thu, 15 Nov 2007 11:51:35 -0800 (PST)
From: Glenn Saunders <[EMAIL PROTECTED]>
Subject: Re: [EVDL] Vectrix braking flaw?
To: Electric Vehicle Discussion List <ev@lists.sjsu.edu>
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset=utf-8
Would it really be that hard to have it rewired if you want it another way?
----- Original Message ----
Currently the right
hand can control both the front and rear brake
(regen). Very confusing for a brain. It should be ?
right hand controls rear and left hand controls front.
------------------------------
Message: 8
Date: Thu, 15 Nov 2007 11:52:41 -0800
From: Roger Stockton <[EMAIL PROTECTED]>
Subject: Re: [EVDL] Vectrix braking flaw?
To: "'[EMAIL PROTECTED]'"
<[EMAIL PROTECTED]>, "'Electric Vehicle Discussion
List'" <ev@lists.sjsu.edu>
Message-ID:
<[EMAIL PROTECTED]>
Content-Type: text/plain; charset="us-ascii"
rubberlegs wrote:
> In my opinion it makes no sense to have braking for both
> front and rear brakes in the same hand.
However, that is in fact the standard control arrangement for motorcycles, at
least in North America. Even on an ICE bike considerable rear wheel braking is
available by rolling off the throttle; I can get enough compression braking on
my ICE twin to bark the rear tire without touching the rear brake.
I am sorry to hear of your mishap, and do hope that you and your bike came
through relatively unscathed, however, it doesn't sound as if there is really
very much to fault about the Vectrix's control arrangement here.
Cheers,
Roger.
------------------------------
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End of EV Digest, Vol 4, Issue 40
*********************************
