Building An Electric Vehicle
An electric vehicle primer.
by
Rod Hower W8RNH
October, 2002
Serial Programming for Ametek BLDC control
Serial Programmer setup http://www.qsl.net/w8rnh/serial_1.0.2.zip
External control DSP http://www.qsl.net/w8rnh/E-68-001.out
Programming instructions http://www.qsl.net/w8rnh/dspflash
SCI program.doc
Ebay
listings
Check out my ebay listings here http://www.qsl.net/w8rnh/ebay/ebay.html
Hower
Family Pics
Pictures of the Family http://www.qsl.net/w8rnh/familyh
Halloween Pictures of the
kids http://www.qsl.net/w8rnh/halloween
Electric
Vehicle Files
Electric Push mower http://www.qsl.net/w8rnh/mower3.jpg
BLDC Dyno with sepex NEV motor http://www.qsl.net/w8rnh/dyno/dyno.html
Electric
Club Car golf cart http://www.qsl.net/w8rnh/golfcart.html
Electric
Go Cart http://www.qsl.net/w8rnh/gocart/gocart.html
TEVan speed switch http://www.qsl.net/w8rnh/speedsw.jpg
TEVan charger control, non PFC, 600kb http://www.qsl.net/w8rnh/chgcntrl.pdf
TEVan battery charger, non PFC, 1Mb http://www.qsl.net/w8rnh/battchgr.pdf
TEVan battery charger, non PFC, 4Mb http://www.qsl.net/w8rnh/batchgr.pdf
TEVan battery charger, text description http://www.qsl.net/w8rnh/chgrdesc.txt
Electric Scooter Pictures http://www.qsl.net/w8rnh/scooterh
Dodge TEVan, Electric Vehicle
http://www.qsl.net/w8rnh/tevanh
Fiero Electric Vehicle http://www.qsl.net/w8rnh/fiero
GE Elec Trac Electric Lawn Mower http://www.qsl.net/w8rnh/etrakh
GE Elec Trac Speed control schematic http://www.qsl.net/w8rnh/etrakh/ELECTRAK.PDF
Various Electric Vehicles http://www.qsl.net/w8rnh/evh
SCR control schematic http://www.qsl.net/w8rnh/SCRDC_control.pdf
Curtis 1221 control schematic
http://www.qsl.net/w8rnh/curtisschematic.pdf
EVT15 GE control schematic http://www.qsl.net/w8rnh/evt15.pdf
108V GE motor speed torque
curve http://www.qsl.net/w8rnh/108vmotor.pdf
GE motor mechanical drawing http://www.qsl.net/w8rnh/motormech.pdf
TEVan motor control
elementary http://www.qsl.net/w8rnh/TEVanelem.pdf
Shunt motor 96V
Mechanical http://www.qsl.net/w8rnh/B104mecs.jpg
Shunt Motor 96V data http://www.qsl.net/w8rnh/B104shns.jpg
Shunt control picture http://www.qsl.net/w8rnh/shntcnt2.jpg
Shunt control inside http://www.qsl.net/w8rnh/shntctr1.jpg
Amateur
Radio
Cat1000 Repeater controller
manual http://www.qsl.net/w8rnh/c1000manual.pdf
Our
repeater controller is located in Akron, Ohio
442.600
MHz, 131.8 PL maintained by Rod Hower and installed at
Dan
Testa's repeater site on top of 'the hill' at Portage Lakes.
The repeater site at Mud Lake
Http://www.qsl.net/w8rnh/repeater.jpg
This site is located at top of
the hill, the antenna is barely visible
This site is frequented by
the 'club' ------
WD8MDF -Dan Testa,
(Proprietor) N8WNO - Donna Testa
W8RNH -Rod Hower, N8WUX-
Sherri Hower
WD8MDE - Larry Fazenbaker
WB2DFC - Dave Rarrick
K8WRP, 'warp' or Jim the PLC
computer wizard guy
And many other amateurs in
the area.
Geocaching
What is Geocaching? www.geocaching.com
A geocacher looks for hidden
treasures at a specific site.
You can find these by
entering latitude and longitude in your GPS and follow the
Clues to find a 'Site'. The
cache is a waterproof container that holds small treasures
From other geocacher's such
as keychains, toys and other misc. stuff.
Sometimes a where's george is
hidden www.wheresgeorge.com
Here's some pictures of me
and the kids finding a cache.
http://www.qsl.net/w8rnh/cachepark.jpg
http://www.qsl.net/w8rnh/Firestonecache.jpg
http://www.qsl.net/w8rnh/kyle
clinton.jpg
Many
folks have emailed me about how I built my electric van, and want to know what
they need to do to build their own, or where they can get plans. Rather than
retype the same note over and over again for general information requests, I
typed up this info page which should answer most questions. I really enjoy
detailed debates on technical issues, so if you have any questions about the
how's or why's of EV's, please send your inquiries my way.
Why Drive an EV?
First off, I built
my EV not because I'm a tree hugger but because the idea of an electric car has
always intrigued me. I bought my Dodge TEVan from Mike Chancey. He has lots of
cool EV's Pictured at www.austinev.org/evalbum.html
The initial
"sticker shock" of some of the EV component costs (motor, controller,
batteries, etc.) made me think twice at the outset, but as years and miles
accumulated on the truck, the idea nagged more and more. The turning point was
discovering there was an Electric Auto Association chapter right here in
Albuquerque, and at my first meeting got to meet folks who not only had the
same interest, but had real electric cars to drive. After much investigation
and self-education on all the pertinent facets of building and driving an
electric car, the plans were set in place to convert my S-10. I used only
current mainstream parts and processes, I wanted to leave little to chance that
this project would fail. It turns out (in hindsight) that it was wildly
successful, after several years and tens of thousands of miles of use there
have been virtually no unexpected problems. For day-to-day commuting and
slugging out honey-do's on the weekends it's tough to beat an EV for
reliability, convenience and economy.
Which EV is for you?
The first
observation I had starting out was that there is really very little formal
written documentation on building electric cars.
This is largely because there are
virtually no two alike, both in electric drivetrain and chassis used. Currently
your only option to buy an electric car is one that's been converted by someone
else, or buy a Solectria converted new Geo Metro (built in MA) for $30K or so.
In selected areas you can *lease* a GM EV1 coupe or a Ford Ranger EV, but it's
such a narrow market segment I don't think it's worth mentioning. I only count
road EV's, there are a lot of folks out there that think some of these
golf-cart sized Neighborhood Electric Vehicles (NEV's) are adequate. In my
view, if you can't drive it on the freeway it's not a real EV. For those of us
in the trenches, the process for either selecting a vehicle to buy (there are
forums for buying/selling used EV's) or building your own starts with
determining what the vehicle will be used for. Most americans drive less than
30 miles a day, which just about any EV will do easily.
The goal is
to tailor the EV (or select it) to meet the average daily mileage needs you
have while performing the job you need to do. For long trips you have your gas
car, rental car, airplane, etc. The chassis (car or truck) you pick, battery
sizes and types, motor size, controller size, etc. will all be based on what
this vehicle will do on a daily basis. You
can't haul tree branches to the dump in a VW bug, or fit a family of 5 in a small
pickup. You also need to be realistic in your range requirements. It's easy to
say at the outset "I want all the range I can get" but there are
downsides. Range equals pounds of batteries, the more batteries you have the
further you will go. But the more batteries you have the *slower* you will go,
and the bigger (and more expensive) motor and controller you will need. Costs
of building the EV come into play too, but not as much as the intended use. The
individual component costs compared to the total package costs really isn't
huge between different types of EV's. It's the functions and capabilities of
those components combined with the right chassis that will make the difference
between a successful and impractical EV.
Donor Chassis Considerations
OK, now that
I've gotten all the philosophical stuff out of the way, here are the nuts and
bolts. Converting a gasoline vehicle to electric power is the ultimate form of
recycling. You are taking a polluting vehicle and changing it to a less
polluting one, while at the same time extending it's useful life by keeping it
out of the salvage yards for a while longer. It helps to pick a car/truck you
love. You will know it inside and out and will touch virtually every aspect of
it's construction. You will need to pick one you can get parts for well into
the future, not some obscure foreign job that you have to scrap when you can't
find a ball joint (or whatever) for it. Pick one that's in decent shape. If it's
a gasoline junker, it will end up being an electric junker. Just making a car
electric doesn't fix torn seats, shot brakes, rust holes and cracked
windshields.
The hardest
part of any conversion is the battery frames. This is why it's very important
to know exactly which batteries you will be using way ahead of time, otherwise
you will have no idea how to place the frames. Having a welder (arc preferred),
or having a friend with a welder that knows how to weld is key to doing this
economically. It involves welding the various brackets and boxes, and
permanently affixing them in various spots within the chassis. Nuts and bolts
are not acceptable, as they are prone to coming undone, have questionable crash
integrity and don't have the required stiffness to prevent fatigue at other
stress points. Because we're talking some serious weights here (the pack in my
truck is almost 1400lb.) it's not enough to just set them in the bed of a
truck, or in the trunk of a car.
They need to
be adequately restrained by some serious steel, with the mounting points
distributed with enough surface area to absorb impacts and vibration without
fatigue or coming apart. The second hardest part is getting the motor to
transmission adapter properly implemented. Not because it's a particularly
tricky process but because auto manufacturers aren't necessarily consistent
from model year to model year. It's virtually impossible for the adapter
machinists to maintain templates and data for all the possible transmission
models and combinations. Once the motor and batteries are mounted the rest is
easy, and almost fun. The electricals are usually very simple, and the remaining
supporting componentry is fairly standard and straightforward. There are
incidentals like air conditioning, power steering, heat, etc. but they are
usually never any more difficult than identifying the proper componentry to buy
and installing it.
EV Drive Components
There are
limited choices for motors and controllers that are *proven*, and only a few
more that are unproven. Stick with the proven stuff, the pat rule I follow is
an Advanced DC, Inc. 8-inch motor for cars, an 9-inch model for trucks. You
can't go wrong with those. The alternatives are 2X the price but not 2X the
gain. For the low end of the motor controller spectrum I would go with a Curtis
1231, for the mid end I would use a DCP 600, for high end I would buy a DCP
1200.
There are
others out there but are not commonly used and if they fail you have limited repair
options, even under warranty. Batteries are a *hugely* debated topic, there are
as many opinions on which batteries to use as there are different types of
batteries. In my opinion, for real-world EV use there are only two choices,
Trojan brand flooded lead-acid, or Optima brand sealed lead acid.
Each has
their advantages when it comes to performance, capacity, cost and longevity, so
only you can decide which of those features you desire, limited only by the
size/type of your EV and the depth of your wallet. If you've got the big bucks
you can get flooded NiCads but they need different care and charging
considerations. No other battery technology is available today (to us in the
trenches) for EV's other than these two (lead acid and nicad).
EV Sticker Shock
One thing
that bugged me when I first got into pricing EV parts was that there *must* be
a cheaper way out. The EV parts suppliers must be putting a big markup on this
stuff, or that there is some substitute somewhere that will work just as good
at less cost. Well, the answer is there ain't no free lunch. There are lots of
electric motors, controllers and batteries out there but at the voltages and
currents a road EV needs, the available selection narrows considerably. You
hear stories of using surplus aircraft engine starters, forklift relay speed
controls, Sam's Club marine batteries, etc., but even if they hold up past
their maiden voyage, they're certainly not dependable or powerful enough to
serve other than occasional fun trips. Walk into a Grainger or a Graybar store
and start asking about 30HP DC motors, 500 Amp DC fuses, 50 kilowatt motor
controllers and they'll just give you a deer-in-the-headlight stare.
EV's are on
the very edge of what is available, so be prepared to pay the price. The
dealers that are out there are definitely *not* getting rich on the backs of us
poor slobs doing conversions. While the prices are kind of steep, the good news
is that failures aren't that common. With the exception of the batteries, the
EV driveline can outlast several donor car chassis (hundreds of thousands of
miles). So you pay a lot up front, but it's likely you won't spend anything in
(electrical) maintenance or repairs for a very long time. This longevity also
promotes high resale values because the parts don't lose much value over time.
You can likely recover most of your (EV component) costs when it comes time to
sell it, with the possible exception of the batteries.
Kits and Plans
If you want
to take some of the guesswork out of building your own, there are a couple of
suppliers that sell "kits" that fit older Geo Metro's, VW Rabbits and
S-10 Pickups. The kits you might see do not usually include battery frames, so
that work is up to you. I'm not a big fan of these kits because you typically
don't get exactly what you want, and you really don't save that much money over
selecting the exact components you really do want. Plus, unless you're a fan of
Geo's, Rabbits, or S-10's, the only way a kit would work out is if you wanted
one of those vehicles specifically. But there is a lot to be said for having
the knowlege and experience of those who put those kits together to help you
through it.
Buying a Pre-Converted EV
Now, if you've gotten this far and your eyes are crossed and think all of
this is beyond your capabilities, you can always buy a pre-converted (used) EV.
There are numerous internet forums for buying and selling privately converted
and owned EV's, here is a list to get you started:
EV Sale Sites (as of Oct 2001)
There's a bit of sticker shock in buying a used EV too, largely because of
the parts costs (and value), plus all the labor it takes to convert a car. I
have well over 500 hours invested in building mine, even at minimum wage that's
a pretty good chunk of change. So don't look at it as a 10 year old Escort or
whatever selling for ten times what the ICE version would, think of it as an EV
you can buy for less than what it would probably cost to do it yourself. If
it's a vehicle that you can easily get parts for, it's age isn't much of an
issue.
EV Organizations
Whether buying or building, having a local Electric Auto Association (EAA)
chapter in your area is a huge help in finding out EV information. I highly recommend
going to those meetings to get to know some EV'ers and see their machines.
While in my opinion the return on the EAA dues is somewhat questionable, it's
currently the only national organization for private conversion enthusiasts. If
you don't have access to the internet, or don't want to take the time to search
for internet news about EV's, the EAA's Current Events newsletter might be of
interest. See the organizations's website at:
The Electric Auto Association - http://www.eaaev.org
Recommended Reading
As far as formal published information there isn't much, but there's one
book that's a must-have, whether you're converting yourself or buying a
conversion. It's "Build Your Own Electric Vehicle" by Bob Brant.
(ISBN #0-8036-4231-5) He goes into immense detail and explains the theory and
the physics of EV parts like batteries, motors and controllers. It's not about
*how* to build an EV (contrary to the title) but how they work. It's a great
reference, I use mine all the time.
Internet Info Resources
Clearly the best source of information is on the web. Type "Electric
Vehicle" in any of the search engines and you'll get many thousands of
sites to visit. It's a great inspiration to see what others have done and built
for their EV's and a great way to share data and ideas. Here is a list of some
of the better internet sites: (Compiled Oct 2001)
Another tremendous source of
information is the Electric Vehicle Discussion List, an email forum that brings
together hundreds of EV'ers from all over the world, who's combined knowledge
is the sum total of all that is known about electric cars. There isn't a
question you could ask that someone on the list doesn't know the answer to. Of
course you need email to participate, but it'd be worth getting set up with an
old computer and a free email account just for this alone.
Instructions and info on the EV Discussion List
http://www.madkatz.com/ev/evlist.html
Conclusion
Well, that's about it for the basics. Just like any other avocation there
are many nuances and specialties you can concentrate your interest in, but for
now this should be enough to get you started. EV's are a really fun hobby with
a practical side to them. You can drive your hobby to work or to the store and
is an instant attention-getter wherever you park. I ended up learning much more
than I ever wanted to about high power electrical and electronic things,
motors, batteries and such, but the more you learn the more you *want* to
learn.
Rod Hower W8RNH [email protected]
1994 Chrysler TEVan http://www.qsl.net/w8rnh
Last Revised October, 2002