[TexomaEV]

Thanks for the heads up on that club website, I'll see what I can find. My brother and I would like to make a trip up there and purchase 2 to 4 of them and bring home to convert to electric.

On the motor, I'd look at the PMG-132 permanent magnet motor.

www.enigmaindustries.com/PMG_132/PMG_132.htm

It's small and pretty powerful. I've seen a conversion awhile back using 2 of these for an all electric mode EV.

[david85]

5x1.5x3 feet is a usable amount of space. Since this is inside the car, flooded lead acid batteries are not a good choice, but a small lithium pack might be a good fit. If you are not looking for an 80Km range, than the pack can be fairly small, LionEV should be able to set you up with something suitable.

For motors, there are more choices out there than I can imagine in this size range, this is the tip of the iceberg: http://www.electricvehiclesusa.com/category_s/141.htm

And if all you need is 5 Hp, than you won't have to spend much on it either.

[booneylander]

Thanks guys, a lot of good info there.

I think the Perm motor might be particularly well suited with it's small size and seemingly high efficiency.

Time for me to spend some time in SolidWorks!

[xrotaryguy]

One more thought. The Saturn Vue Greenline uses a motor/generator in the place of an alternator. What about the possibility of using something like that? It sounds like you already have your spage issues worked out, but this could cut down on weight too. I guess you could go one of two ways on this: The motor could be a 12v unit that would charge a bank of parallel wired 12v batteries. I don't know that a 12v unit would get you much motor speed thought. Or, the motor could be 48v, 72v, etc with regenerative capabilities. You would need a power converter to send the necessary amount of power to the accessory/starter battery and the rest to the traction pack. The programming for such a setup could get pretty complicated though. Oh, I guess if you have a motor/generator attached to the front pulley of the car, you may not need a starter at all.

[mattW]

Yeah hopefully this could replace the starter and alternator without too much difficulty. With electric motors the higher the amps the better efficiency and power wise. I like the idea of that 72V permanent magnet motor and it is a good size too. To test the concept you could just buy 6 12V (or 12 6V if you have the room) flooded lead acid batteries which would be reasonably cheap while you work out all the kinks and then upgrade to more advanced batteries in 3-4 years when they start to wear out. The Altrax controllers look suitable for 72V but I don't know if they have regen. It wouldn't be too hard to implement with some electronics. So we are looking at 900 for the motor, 500 for the controller another $1000 for some lead acids ~5kWh (at 1hr rate), maybe 250-300 for a charger (quick google shows this one). Probably around $3000ish all up to convert to a plug in hybrid which is pretty good value if you ask me! Bigger tyres would help take advantage of the extra torque. I'm pretty interested in this concept actually.

[booneylander]

My plan was to leave the starter/alternator in place with the normal 12V system intact, then have the electric motor and all of it's system totally seperate. The computer control is into every nook and cranny of the car and I think I will avoid a lot of potential problems by keeping the systems seperate (for now). Also I would have to go with a much more sophisticated motor (AC induction, right?) if I wanted to do Regenerative Braking, so here the cost goes up significantly.

What if I used the existing alternator hooked to an inverter and a charger to charge the 72V pack though, with some relays set up so that the inverter only switch on when trying to brake. The extra load of the alternator on the engine would provide some Regenerative Braking. I imagine though that the stock alternator wouldn't be powerful enough to slow the engine much, and you would probably end up depleting the 12V battery during that time and then recharging it while you were back up to speed which would kind of defeat the purpose....

Maybe after I get the basic concept built and working though I could think about replacing the starter and alternator with a better electric motor and then have a new fuel management system so that I could regen brake, and have the engine turn off at stop lights and such and get going again on electric power similar to a commercial hybrid car. That would actually open up a lot of possibilities on the ICE side too, I could install a larger more efficient turbo and not have it spool until a higher rpm, without having to worry about having no torque down low...

[mattW]

Here is an article you might find interesting about a fully engineered diesel electric hybrid. It kept the starter but used the motor and a DC-DC converter instead of an alternator. 30% improvement in efficiency! A very good point to start with your conversion.

[booneylander]

Particularly interesting is the fact they mention that to optimize the performance of the diesel engine, they actually apply a generator load in some situations to charge the batteries since diesels are most efficient at low rpm with higher load. That's a particularly clever approach.

[xrotaryguy]

Originally Posted by blooneylander

The computer control is into every nook and cranny of the car

Yea, I have heard that the electronics are quite extensive on that car. I believe that the braking system is even programmed to keep the car upright (a challenge in such a short-wheelbase, tall skinny car) in a collision by selectively braking specific wheels based off of inputs from accelerometers, yaw sensors, etc. I wouldn't want to mess with a system like that.

Keep is simple for now. Remember drop dead Fred. Baby steps. Baby steps.

I wouldn't use the alternator to charge the traction pack. It will only increase the duty cycle of the alternator and wear it out. And you're right, the alternator will not provide a noticeable amount of braking.

Originally Posted by blooneylander

Maybe after I get the basic concept built and working though I could think about replacing the starter and alternator with a better electric motor and then have a new fuel management system so that I could regen brake, and have the engine turn off at stop lights and such and get going again on electric power similar to a commercial hybrid car. That would actually open up a lot of possibilities on the ICE side too, I could install a larger more efficient turbo and not have it spool until a higher rpm, without having to worry about having no torque down low...

You would not be able to run the car on electric only with your dc motor driving the front pulley of the diesel motor. This is the case with Saturn's hybrid Vue too. I guess that's the downside of a low buck hybrid design. Leave it to GM to cheap-out on engineering.

I personally would not mess with engine displacement either. I am relatively certain that the small displacement motor w/ turbo makes more sense than a larger diesel motor. That is really the only marketable way to run a diesel in a small car. I realize that you are not talking about going to a Cummins I-6, but the fact remains that diesel motors are very heavy given their displacement. The most practical way to get good torque out of a small diesel powered car is to pressurize the intake manifold. Of course, you would already have the added weight of a motor, controller, charger (maybe), and batteries, etc to consider if you were interested in adding a larger diesel motor. That would be one heavy little car.

[booneylander]

Originally Posted by xrotaryguy

I personally would not mess with engine displacement either. I am relatively certain that the small displacement motor w/ turbo makes more sense than a larger diesel motor. That is really the only marketable way to run a diesel in a small car. I realize that you are not talking about going to a Cummins I-6, but the fact remains that diesel motors are very heavy given their displacement. The most practical way to get good torque out of a small diesel powered car is to pressurize the intake manifold. Of course, you would already have the added weight of a motor, controller, charger (maybe), and batteries, etc to consider if you were interested in adding a larger diesel motor. That would be one heavy little car.

Sorry, I meant just swap the turbo to a larger one, not swap the whole engine. A larger turbo will often be more efficient but at the expense of requiring higher rpms before it starts producing any boost.