[alpa]

Hi,
This is my first post here. Not sure I'm posting in the right section or even on the right forum .
I wonder if somebody here is converting a petrol car into a hybrid one. I'm especially interested in this topic to convert old cars like my classic manual Mini.
My idea is to replace the alternator with a few KW DC (brushless) motor. It would help the engine to make accelerate the car and during low speed cruise phases (in town). During this periods the IC would run in the stratified mode just to maintain itself in rotation to avoid wasting electric power on the compression work (no variable valve lift in old engines). The motor would also act as an alternator. An electric throttle (like) device is of course mandatory.
Any input would help.
Thanks

[madderscience]

Hello-

These forums are largely focused on pure EV conversions, but we do have a few other people considering hybrid conversion concepts.

The easiest thing to do if you want a homebuilt hybrid seems to be to find an all-wheel drive car and disconnect the rear axle from the rest of the drivetrain and hook an electric motor straight to it, then add the rest of the EV components (batteries, controller, etc) to power it. In the case of a mini this would mean installing such an axle from another vehicle. The big disadvantage of this system would be even more weight than an EV conversion, since you did not save any weight by removing the engine, fuel tank, etc.

Another alternative would be to try and fit the drivetrain from a wrecked hybrid vehicle into the mini, but I know there is not much room in there; not sure what sort of micro-compact hybrids might be available in europe.

As for your idea, I'm not sure you could get enough power through the fan belt of the car to significantly assist the engine. And you'd still need an alternator or something else to run the 12V system in the car anyway.

Depending on your needs though, the mini would make a neat little (pure) EV.

What about a smart car diesel engine and transaxle? I bet that would work, though it isn't EV at all.

Good Luck.

[mxmtech]

I've been doing a little thinking about this as well.
My idea is to use a front wheel drive vehicle like the Geo Metro and convert it to electric putting the batteries in the back.
Then take a Volkswagon transaxle and build a compatible frame that would interchange with the Geo battery pack.
City driving - slide in the rear wheel pack with the batteries.
Going on a trip - slide in the rear wheel pack with the ICE complete with gas tank.
Not really a hybrid, more like an instant conversion pack.

[alpa]

Converting to a pure EV is not an option. I live in a stupid country France where conversions are totally forbidden because there is no way to register a petrol car as an electric one. The IC engine must be physically present and I have to produce CO at least during smog.
Also the same question will arise for many other classic cars, people don't want to deeply modify them while they like the EV smooth and clean driving.

A Mini is a light car (650kg) so driving it through a multi-v belt like the one used for A/C or superchargers is perfectly enough, 5HP are enough to cruise in town and start the car on traffic light.
A DC motor will serve as alternator when not being used to drive the car.

My first plan was to install a second (electric) engine at the rear. Mini has a special setup with the gearbox under the engine, so putting the entire front engine frame with the gearbox solves lots of problems. Then bolt a motor in place of the IC engine. I even bought a rusted Mini to make a prototype of the installation. However I realize now it's quite complicated because there are so few room in the car, and now there are very compact DC motors I can just bolt in place of the alternator.

The basic idea of the management is simple: while the demanded load is low the DC motor drives the car and the IC engine is just barely idling, there is no need for a good quality idle as the DC motor will smooth the RPM. During this phase the IC engine is never in the transient mode, which is the most petrol consuming.
When the car is stopped and batteries (say 2 x 100Ah deep discharge lead-acid) are charged the engine goes down to 500 RPM idle (it works perfectly on my engine), the alternator stops working and the car peripherals stay on batteries.
On a high load demand the DC either helps the IC or it's switched to an alternator mode.
A start/stop IC engine system is also to be studied. However the warm "clean" IC start-up is still a mystery to me, I'm not sure old engines especially like the Mini's one are able to do that. I'm more thinking of dynamic cylinder switching off.

[dataman19]

Alpa,
Have you considered a planetary gear box?
This is the Prius gearbox.
The planetary gear assembly would allow for two separate power plants.
..
When both power plants are producing power - then the power produced would be the sum of the two.
..
When only one power plant is producing power - then the power applied would be roughly equal to the power capacity of the power plant producing power to the drive wheels...
Now, in reality, you have a slight decrease in efficiency (about 2% to 5%) with a planetary gear set. But the overall gain is a whole lot better than not when using two sepratae power plants.
..
Want to know more about gear sets? Here is an excellent tutorial (even has animations to illustrate the points):
http://www.carbibles.com/transmission_bible.html
..
Pay particular attention to the planetary gears sets used in auto transmisstions. ::
...
If you Drive the outer ring with the electric motor, and the planetary gears with the gasoline motor - you essentially have a Prius Hybrid drive train.
..
Dave Mason
dataman19

[alpa]

Dave,
The only feasible mod I could imagine would be to modify an auto transmission, luckily it existed on Mini.
However I don't see how/where would I connect the second motor in the chain of planetary gears. There is one input, one output in the gearbox.

[dataman19]

You would have to have a gear re-machined in a machine shop to add an output shaft (or find a Prius in a salvage yard).

[gor]

Originally Posted by alpa

Hi,
This is my first post here. Not sure I'm posting in the right section or even on the right forum .
I wonder if somebody here is converting a petrol car into a hybrid one. I'm especially interested in this topic to convert old cars like my classic manual Mini.
My idea is to replace the alternator with a few KW DC (brushless) motor. It would help the engine to make accelerate the car and during low speed cruise phases (in town). During this periods the IC would run in the stratified mode just to maintain itself in rotation to avoid wasting electric power on the compression work (no variable valve lift in old engines). The motor would also act as an alternator. An electric throttle (like) device is of course mandatory.
Any input would help.
Thanks

well, to have a parallel electric plug-inn system, tapped to engine, shaft or wheels - helps engine to run easier,cooler, on lower rpm -good idea, how to achieve it with easy mod - good question;
look for hybrid types and "electric supercharger" on the web, Saturn hybrids - i believe?
p.s. it is easy to tap to alternator or to serpentine belt, though less complications for existing car electronics would be to tap right after the clutch before gear mash or use wheelhubmotors (rear for FWD)
p.p.s. somebody been messing with the starter outlet on flywheel -but i belive they desided it's beter to leve starter alone...

[alpa]

gor,
I made a search for Saturn technology description. Looks like it's a wonderful thing (according to US sites) but nobody is able to tell more than it's a hybrid with an electric motor/alternator.
Would you have a pointer to a better description of this thing ?

[gor]

Originally Posted by alpa

gor,
I made a search for Saturn technology description. Looks like it's a wonderful thing (according to US sites) but nobody is able to tell more than it's a hybrid with an electric motor/alternator.
Would you have a pointer to a better description of this thing ?

yea, i'll check it - it been somewhere... - i'm interested too -at least it would enhance performance without much damage to staff(car,etc) you (i) already have : ))))))
i'm interested too - in outroad application it seems like hybrid drive - could be a good option