Did you ever think about installing a powerful electric motor to make the car hybrid like Prius or Insight ?
This is a front wheel powered car.
But it has a generic transmission and differential so that a similar "4x4" differential can be installed and the drive shaft can be connected to an electric motor fitted in the luggage compartment. Also the extra batteries can be put to the luggage compartment too.
The system works obviously that when you press brake pedal motor will slow down the car charging the batteries and when you press accelerator pedal batteries will run the electric motor in order to help the engine during accelerating or when on least efficient rpms ..
I know you will say: "Unnecessaryly hard to do so" or: "This will ruin the car especially the luggage compartment" or: "Buy a more fuel efficient or a hybrid car" or "This system will be very expensive so dont worth the money for fuel economy" But this is not the point here.
Lets discuss this subject briefly...
What do you think this "whole" extra systems weight is ?
How much extra frictional drag will it create? Or in other words: Do you think it can be efficiently applied in order to get more fuel economy especially in stop-go city driving?
What about the batteries ? Can ordinary car batteries connected parallel or series is suitable for this continuosly charging and uncharging situations ? What about the motor ? What kind and type of motor is most suitable for this job? and what about the control circuits ? for charging and decharging the batteries in order to run the motor in both "generator" and "electric motor" mode ? and also what about integrating the system to work smoothly in conjuction with the engine and brakes ?
How can it be done ?
For a while I wanted to do this to a car. I was thinking of getting a VW Bug and powering the rear on gas and the front wheels on electric. I figured I could drive around town in electric and if the power ran out i would flip a switch and turn on the gas motor.
This, of course, would take a lot of time and resources, neither of which I have much of now adays
As for the type of motor to use, I would look at the possibilities of using some kind of series wound DC electric motor. These motors generate more torque at lower RPMs, therefore if they are driving a car up a hill, say, and the car begins to slow down, naturally the motor will produce more torque to keep the car moving. Starter motors in cars are series wound.
A series wound motor may not be practical though [I'm really just brainstorming], and you might need a compound wound motor instead.
i've been thinking about this issue too. but i would take a much different approach than trying to integrate a custom hybrid system within an existing gas car.
let me back up for a second to show where i got my idea:
if you're familiar with existing electric vehicles (EVs) (conversions, mostly), you know that they're often limited in range - 20-50 miles is common. to permit the cars to take longer trips, several industrious EV owners have constructed custom trailers which either (a) carry extra batteries, (b) carry a generator to charge the batteries while driving (essentially making it a gas/electric hybrid), or (c) have a self-contained internal combustion drivetrain that actually pushes the vehicle (also essentially a gas/electric hyrid).
here's an example of (c).
the 944 is a pure EV. the trailer is a fully functional front half of a front-wheel-drive vw rabbit with an automatic transmission, self-contained with shortened exhaust system & fuel tank. the driver has an extra set of controls in the porsche to start & "drive" the pusher trailer once out on the highway. <a href="http://www.jstraubel.com/EVpusher/EVpusher2.htm">here's his web page describing the set up</a>
what i would do is exactly the opposite:
- my "hybrid" would be a small internal combustion (IC) car
- attached to an electric "pusher trailer"
- the trailer would be for sub/urban use only
- electric-only propulsion up to about 30 mph
- with optional regenerative braking
- and plug-in and/or solar recharging
- added benefit: swappable between multiple IC "host" vehicles
i've done a small bit of reading. a 48 volt system with a 10 hp electric motor would suffice for a car the size & weight of a metro (remember the torque advantage of electric motors - don't need high hp).
i already have manual steering, so i can get "pushed" with the metro's engine "off" and still steer with no difficulty. brakes are power assist, but they aren't hard to use un-assisted.
around town, drive it like a prius: gas engine off, pure electric drive up to around 20-30 mph. above that, switch the IC to "on", pop the clutch and continue driving if you need to go faster. disconnect and leave the trailer at home for hwy trips.
no plans to make this, just like thinking about it.
was going to post a page on my site with this idea. maybe i still will eventually.
I like the idea you are proposing. The downside, however, is that I do not always want a trailer behind me. There is also the issue of being pushed, which I'm not too keen on for some reason. Don't ask me to explain, as I cannot.
I originally saw an article on Mother Earth News from the 70s about a guy who converted his Opel to use a DC motor and had a small diesel engine running a generator in the back of his car. He reported getting around 80mpg(US) on this setup. Apparently he also couldn't go above 50mph if he wanted to stay above the charge threshold. That's great for around town, but not so good for long distances.
I'd think that with modern technology this could be reproduced and the 50mph threshold would be much higher. Maybe 75mph is obtainable due to better DC engines and generators.
I'd personally rather build an electric car for around town and keep my civic for road trips. Everyone wins that way
Guy has done the (c) option all with vw rabbit, only has the trailer on long trips, and since it gets 50 mpg non-hybrid, ain't a bad deal. You could also use the trailer as just a generator to recharge the batteries.
I have to agree with Matt on this one -- pushing from a trailer sounds very unstable -- the physics of it makes it look like it could fishtail the vehicle. I can see using the trailer unit as a stand-alone charger only, which also could be mounted inside the vehicle as a "second engine" and save aerodynamic forces.
stability - i would have thought that would be a problem too. but if you read the guy's page he claims he can't make the car unstable (oversteer), even when applying near full power from the trailer in a tight turn (if i'm not mistaken, the gas rabbit had around 70 hp).
and my proposed electric trailer would have just 10 hp.
i'd still have one built if i ever won the lottery
I thought about the trailer idea too. But only during the initial stages of development for testing purposes.
If implementation really works and provides more fuel economy then it would be more suitable to install it in the car. I like modifications for both performance and for fuel economy.
I guess it would be wonderful if the whole systems weight is no more around 150 - 200 kg and a cheap lightweigth 10-20hp electric motor can be found.
My car is an Opel "Vectra B". and i will have to find a cheap "4x4" Opel "Calibra" differential from the junkyard.
But i'm not thinking about going with only electric. This system will only be an "aid" to the engine and an energy recovery system from braking.
By the way i guess big powerful capacitors are needed rather then ordinary car batteries.