EV-1 Conversion

[JCG]

Thanks YP. This has been a ton of fun to do.

Update: gauges!

I've sort-of panel mounted the capacitor voltage meter (which has already been displayed here) along with two new gauges for analog outputs for the controller. To keep things colorful I got both a green and blue LED display. My camera really doesn't like the blue one, really acting like it's too bright. The above picture took a whole lot of photographer work.

The analog outputs are both 0-10 V, and of course need to be scaled to actual values (phase amps and RPM or Hz) somehow. At these low speeds and torques the numbers don't get too high. Notice that regen amps are displayed as positive numbers (AC current), contrasting to what we're used to around here with DC motor monitors.

I tooled around in the garage a bit testing their outputs, here's a video. Notice when I power on the motor (put the car into "forward") there is a current (0.80) that shows up on the meter. That's an excitation current to the motor.

[youtube]QkIXqymddDA[/youtube]

 

[Matthijs]

I just found a video I have never seen before. It about the impact. But I have never seen this particular version before. I just looks like a regular EV-1 with different rear lights. Also take note on the goal introduction date.

[youtube]7yJkdetky38[/youtube]
Link

 

[paultrafalgar]

Truly Awesome, JCG. Could you do a "range test" to tell how far it will go (just driving round and round the garage ) on one charge? I'm assuming that you don't want to/can't take it on the public roads at present.

 

[JCG]

Thanks for the video Matthijs. I feel really bad for the engineers you see in the report. They put a lot of effort behind the car's development, believing that the company was committed to going all the way to production. They had the rug yanked out from under them and a lot of them were let go when the company's priorities shifted.

Paul, I'd really like to just run the car a bit around the neighborhood to get an idea of current draws to the motor at different speeds, but there are no tags on it so it'd be a matter of minutes before I would be stopped. DC's finest even got on my case when I was washing the car parked outside the garage! Driving around the garage for several laps is another possibility, I guess that would be a decent approximation of rush-hour driving in the city. The stop and go definitely eats a lot of charge. I am glad to have the ability to run laps of course, it lets me tune the controller and such.

 

[DaveAK]

This is an awesome project and to have it running around the garage must be a great feeling, but I'm sure it just makes you want to get it out and stretch its legs a bit more. Get it on a trailer and take it to a race track that's having an open circuit day. I'd come and pit crew for you if I wasn't the other side of the country!

(That wouldn't be outside of the GM agreement would it?)

 

[JCG]

Hey Dave, yes - a race track is well within the GM agreement. There are a couple of places around DC to take it, but getting a trailer and transporting it will cost some real dough... once I finish mounting the last of the hardware (accelerator pedal and rear brake system), it'll be time to turn it over for genset installation, which will probably happen up in Michigan. Then we can do some real test drives without recharging out of the wall every couple of miles!

 

[DaveAK]

I bet you could find a willing volunteer with a trailer to help you. I know I would if I had a trailer, and lived a little bit closer than I do. Anyway, I'll continue to keep an eye on your progress and look forward to some video from a track day event.

 

[JCG]

Wrapping things up on this end...

It may not have been too apparent in the videos of driving around, but I was holding the throttle potentiometer in my left hand while doing laps. I had to mount it to the accelerator pedal so that I could finally steer with both hands! I used a cable to tie the pedal to the pot (once mounted) and insured that "flooring it" wouldn't yank the pot off the wall. This setup is a bit more stable and cleaner than it may look from this angle. The cable is fixed on the accelerator arm pretty securely, and goes around the outside of the pedel to keep clear of the driver's foot.

A while back I was mentioning difficulties with the rear brakes, which are electrically-actuated drum brakes. They use 12 V, but applying the full 12 V locks them up immediately (in the manner of an emergency or parking brake). But, I found that applying a variable (lower) voltage would close the brakes more slowly and with less force, so I used a brushed DC motor controller with PWM to fire the motor-driven ball screw actuators that move the drum pads. This is what I did with the brake pedal. Behind the pedal, mounted to the firewall, you can see the Kelly KDS mini brushed controller and the terminal block for all of its inputs and outputs. The RS-232 port there is the interface for programming the controller - which was a must.

The long aluminum arm (actually it's an angle arm, not just a bar - won't bend in the direction of pedal motion) that I have bolted to the pedal face reaches over to the opposite end of the firewall to tie in to another potentiometer which tells the motor controller how much torque to send to the brake pads. The zip tie turned out to be a nice fix with fine adjustment.

One problem with these brakes is that when they are actuated at less that 100%, if you release them (cut power to the ball screw motors), the brakes would not quite open all the way. In order to fix this, I made use of a single pole double throw switch on the pot box, which you can see here labeled with the letters SCO. It's a rigid lever snap action switch, and you can see the top of its lever sandwiched between the big pot lever arm and its stop:

When the switch is released (brake pedal depressed), the motor controller sends its power back to the motors, closing the pads up onto the drums. When you release the brake, the snap action switch closes, and a small 5 V power supply kicks power to the motors in the opposite direction, getting them the last bit of the way open. The 5 V supply is only 10 W, but also operates in intermittent current limiting mode, so it kicks once to open the pads and then gives only small pulses until the next time it switches from "off" (which resets its overload protection) to "on." I couldn't be happier with getting around that problem. The SPDT switch is rated for 25 A too, so it'll handle occasional braking and release currents easily (20 A at the max with the brake pedal floored).

That little motor controller is quite powerful. It delivers 12 V at up to 100 A if you let it. The first time I took a lap around the garage and tried the brake pedal, I squealed the back tires as they locked up. I reprogrammed it to limit the "motor speed" to 30% of the maximum, reduced the motor acceleration rate, limited the maximum current, and now the brakes do their thing a lot smoother.

So I guess that this about does it until the generator set is installed. I have a couple of things to figure out in terms of the magnitude of power draw by the accessory system (motor coolant pump, lights, radiator fan, float charging 12 V batteries, etc.), but everything I can think of is basically in place. The car runs, the lights and brakes work, I have regen, the motor has its coolant flowing, and the CD player works. Can't complain.

 

[Bison_69]

Hi JCG,

This is a fantastic and remarkable achievement you did over there and thank you to reminds us that there is always hope!...

It would interesting if you could contact and have the opinion of its first creator Mr. Alan Cocconi Eng. ‘’Drive System Engineer’’ involved on the GM Impact EV1 prototype project (Founder of AC Propulsion in 1992 and President).
http://www.acpropulsion.com

This guy would be a precious help for you to revive this fabulous EV car…

Mr. Cocconi is now working in an aircraft company called ‘’Solar Flight’’ developing powerful electric motor for larger aircraft.
http://solar-flight.com/sunseekerII/index.html

(the picture of Design News magazine was taken from the web)

 

[bart_dood]

Make a mold of the body so we can make kitcar EV1's.

This

 

[EVan]

Interesting!

BYU did a very similar project back in about 2004 - a donated EV1 was converted with supercaps and a chain driven forklift motor, to do drag racing.

It seems that yours has the original motor and drive. There is the perfect opportunity to stuff that battery tray with 200AH or greater LiFePo4 cells from Thundersky or similar, and you'll have a fast car with incredible range, perhaps better than a Tesla, certainly better than any other production EV today. Please do this!

Turning it into a primarily gas powered hybrid with a noisy, smelly genset on board is.. a bit of a shame IMHO.

But, good work getting it running!

 

[JCG]

Hi Evan,

BYU has been great source of advice for this work - great folks. We learned a long time ago that the installation of Li batteries on the EV-1 would give it 300 mile highway range (according to calculation/simulation), which would have been nice, but there was nowhere near enough money in the budget to get the batteries. The series hybrid approach is intended to show the large difference between peak and base power requirements for a car, and how an ultracapacitor bank can be made to cover the peak load. Then, the base load can be covered with a much smaller engine than you'd normally see.

It's mentioned earlier, but the ammonia engine does not give off smelly exhaust, and in fact gives off no CO2 (only a trace amount actually, if you consider normal side-combustion of engine lubricant).

Battery-only cars are really great for their intended application, but they just can't compete with the energy density of liquid fuels. Find one that's carbon-free and that can be created from renewable sources, and you have a winner (NH3).

I hope that the genset will be tested and in place by the end of the summer. As most people here probably know, the Chevy Volt is due out in the late fall - burning gasoline and using Li batteries that will need sophisticated BMS babysitting and will lose capacity every time that they're charged, eventually needing complete replacement before the car itself does. I would love to beat the Chevy Volt to the punch by using its older brother, the EV-1, to get a carbon-free hybrid with an electrical storage system (ultracaps) that would easily outlast the rest of the car. And to do it spending a few thousand dollars rather than a few billion!

 

[Dicey]

Hi JCG,

Just wanted to say this has been, and I'm sure into the future will be, a fantastic read as you've been converting an EV-1 to a more current powertrain. Keep up the great work on this project. I'm certainly interested to see how the remainder of your project goes.

Dicey

 

[JCG]

Thanks Dicey, I hope to have plenty more updates as the summer progresses. An update for now: the first genset planning meeting will be July 12 in DC. A little later than I'd hoped, but I'm confident we'll move quickly once the groundwork is laid out.

Also, I was sent a list of "talking points" provided by GM to our engineering Dean back in March 2002 to assist him in creating his speech for the donation ceremony. I thought some folks would like to read these, it provides an interesting perspective.

-----------------------------------------
KEY MESSAGES / TALKING POINTS:

General Motors
EV1 DONATION PROGRAM

• The key objective in donating EV1 vehicles is to encourage continued
research and development of advanced technology and environmentally-sustainable
transportation systems, to strengthen GM’s relationships with key engineering
schools, and to provide a legacy for the EV1.

• Schools receiving the donated EV1s are expected to use the vehicles as part
of their engineering curriculums, and for furthering ongoing research in fields
such as electrical engineering, mechanical engineering, aerodynamics, materials
sciences, and automotive design.

• GM plans to donate approximately 40 EV1 vehicles to key engineering schools
and museums.

• If you talk to EV1 owners, you’ll immediately find out they are a proud,
loyal group. Unfortunately, there are not enough of them to provide a
sustainable market.

• However, the EV1 is regarded as one of the most significant automobiles of
the 20th century and is the most energy-efficient vehicle in the world; the
cornerstone for GM’s entry into advanced technology vehicle programs, and has
brought GM to the forefront of developing, and more importantly, actually
building and selling advanced technology vehicles.

• The EV1 was produced with a host of innovations, and was awarded 23 patents
for its advanced features. For example, it’s the world’s most aerodynamic
vehicle (0.19 drag coefficient) at the time of its introduction. The EV1 marked
the first-ever application of a heat pump for cabin cooling and heating, and a
computer-controlled regenerative and hydraulic braking system. As we continued
making improvements to the EV1 drive system, we were also at the same time able
to notch up the battery performance, as well as advancing charging technology.

• GM is proud of the EV1 because we learned a great deal from this program,
such as advances in electronic controls, electric drive systems, aerodynamics,
and the use of lightweight materials.

• This knowledge has proved invaluable to us both in our current model,
high-volume cars and trucks and in our continuing work to develop advanced
electrical, electric hybrid, and fuel cell propulsion systems.

We’re pleased to be able to be here today to share these technologies with
our educational partners through this donation.
-----------------------------------------

 

[GCinDC]

KEY MESSAGES / TALKING POINTS: General Motors EV1 DONATION PROGRAM

That's interesting, JCG, but why don't you just load it up w/ Lithium batteries?

Hahaha! Just kidding! Seriously though, you should post up some of your work on Ammonia. It's pretty persuasive. Seems like the elephant in the room in this thread...

the first genset planning meeting will be July 12 in DC.

What's to be planned? I thought this was being manufactured? Or the whole system, tank, etc?

Any progress w/ license plates? I'd sure love to see this baby tour the mall. (With the windows down, I guess, since there's no AC, right?)

Are you happy with the brakes?

 

[JCG]

the first genset planning meeting will be July 12 in DC.

What's to be planned? I thought this was being manufactured? Or the whole system, tank, etc?

Bingo, Greg - it's the whole system. I'm finally getting a visit from the guy in Michigan, so he can see the trunk with his own eyes. He's got the engine picked out, and thinks it'll fit, but we need to plan for more than the engine. Also the generator head, a small radiator, the tank, and the SCR phase angle current limiter... man I need more money. Another thing that needs doing is tuning the engine's controller for ammonia fuel.

The brakes are almost where I want them. I have one last tweak to make, then I have to check something about the DC converter. Plenty of time for that before July 12 (hopefully)!

 

[Matthijs]

Any updates? Look who took a drive in another EV-1:

[youtube]c1XwPQeG49w[/youtube]
Link

 

[paultrafalgar]

This guy converted his chevy to ammonia 25 years ago, but noone was interested:
http://www.youtube.com/watch?v=L0hBAz6MxC4
...
update here:
http://www.nh3fuel.com/

 

[paultrafalgar]

...and here's where the ammonia comes from - wind:
http://renewables.morris.umn.edu/wind/ammonia/

 

[JCG]

Hey Paul,

Greg was actually running an ammonia-propane mix (which he called "hydrofuel") in that Impala, not quite carbon-free but an important step forward. The Chevy probably had about an 10:1 compression ratio as well. A lot of work is underway now to eliminate the need for carbon-bearing combustion promoters, or in some cases to use promoters derived from biofuels.

Using renewables to make ammonia is pretty exciting. For a long time hydro power was used to drive water electrolysis and air separations to generate ammonia in Norway. There's a large group in the US that has been pushing ammonia as a fuel for several years now, and in case anyone's interested there's a conference coming up this fall:

http://www.energy.iastate.edu/Renewable/ammonia/ammonia/2010/NH32010.html

Really hoping to display the EV-1 there.

 

[paultrafalgar]

Hey JCG,
Moved my ammonia intervention to here:
http://endless-sphere.com/forums/viewtopic.php?f=1&t=20325
so as not to hijack your EV1 thread.
Best wishes,
Paul

 

[GCinDC]

... we need to plan for more than the engine. Also the generator head, a small radiator, the tank, and the SCR phase angle current limiter... man I need more money. Another thing that needs doing is tuning the engine's controller for ammonia fuel.

Quiet summer. Any news?

 

[JCG]

Hi Greg,

Engine testing with ammonia in a converted 4-cylinder Toyota diesel (2.5 L, good for tests but too big to be the actual donor engine), and some rebuilding is necessary due to a bent push rod. Didn't make the deadline for the NH3 conference in Detroit (which ended yesterday). Good news is that we've located a good 2 cylinder block that should work nicely. I'm going to keep hounding the supplier about that. I have heard that another dollop of GM money may be arriving soon to help wrap up the project, which would be great as I'm ready to get the generator head and phase angle current limiter for charging the caps (already have heavy 3 phase rectifier to go between the AC and DC sides). Should be an active winter.

 

[paultrafalgar]

Hey JCG,
What's new?

 

[JCG]

Hey Paul,

Sometimes no news is good news. Though the project's funding hasn't been restored yet (it should be in place by the New Year), our presentation at the Ammonia Fuel Network meeting in September has been making the rounds. A group of investors has offered to buy an engine for further testing in Michigan - meaning the diesel won't need to be rebuilt again. The fuel and engine style (direct injection gasoline, usually found on very expensive cars) have caused this to take on a life of its own. In the meantime, I'm ready to purchase the generator head and SCR power controller once the GM funding is restored to the project. If something hits a snag and delays the work on the EV-1, I'll probably get my own engine, probably a 2-cylinder air-cooled diesel. But it's looking like a February-March time frame to make that decision.

Jason