Concept for downsized full hybrid
 

Hello everyone,

I already posted about a university project on hybrid cars that I'm working on a couple of weeks ago. We're now one step further and are trying to develop new hybrid drive concepts. The goal is to develop a downsized version of a full hybrid that makes it possible to drive short distances (3 miles) at low speeds (around 10 mph). The reasoning behind such a system is that it should be possible for drivers to use their cars in zero emission zones (these zones are increasingly discussed and implemented in European cities).

There are a couple of ways how such a downsized HEV could look like. We could either develop a small in-wheel motor, have an electric motor propelling the axel that is not the drive axle, or have an electric motor connected to the transmission (similar as in mild hybrids). This is what I can think of, but there might be other ways of doing it. Since costs should be kept at a minimum, there might be benefits of not connecting the electric motor to the driveline.

I've seen that some of you have been working on electric conversions, and I was wondering what you think of this downsized full-hybrid. Can you think of other ways how our goal (short distance-low speed EV) could be reached?

Would be great to get some insights from you. There's a lot of information about such concepts out there but I haven't come across a lot of people who actually tried and managed to either convert their cars completely or add an EV mode themselves.

/Johannes

sounds to me like you need an electric golf cart.....

That's exactly what we don't need ;)

Currently, drivers of cars with ICs are not allowed to enter zero-emission zones. They either have to walk to their destination or use public transport. The benefit of a downsized full hybrid is that they can drive to their final destination or do their shopping without having to change their mode of transportation.

I'm not sure why you want a 'downsized' full hybrid. As it is, most hybrids can barely eek out 1 mile of EV range.

You're right, the EV range of many hybrids is low, although it has become much better in new models.

The difference to existing hybrids would be that the electric motor only has to move the car very slowly, so energy demands are lower. The electric motor could also give additional boost to the ICE, but the goal is to have a traditional ICE car (no matter of what size) that has an EV mode to enter zero-emission zones.

Due to the area of operation, the power of such a car's electric motor wouldn't necessarily have to match those of EVs or current HEVs.

You might try a 5th wheel EV mod like the one in Mike Dabrowski's Honda Insight.

http://99mpg.com/Projectcars/mikesinsight/the5thwheel/

How about a big balloon for the emissions?

The existing hybrids also have limited speed on pure electric power - 50 kph in the Prius.

16 kph seems a very low speed - even for these kind of zones.
30kph (19 mph) seems more reasonable, and will be a far more common speed limit anyway.

Combining both IC and electric engines for simultaneous operation is a serious challenge.

It's far easier to shut one down, and start the other one on the go.
Most cars here in Europe are front wheel drive, so they have 2 wheels just sitting there that could relatively easily be converted to electric drive wheels.

i.e. something like a more sensible version of the Volvo V60 hybrid
(Diesel front drive, electric rear drive)

That's true, but that would increase the energy demand, which should be kept at a minimum. I'm wondering what kind of engine you'd need to go 15kph (or 30kph) for 5km. Would 5kW do the job? Any thoughts on that?

That's why we thought about in-wheel motors and about propelling the dead axle like in the V60 you mentioned.

Have you heard of any people who try to develop such things? The fifth wheel basjoos mentioned is an interesting concept. I'd just like to make it look nicer :D

that is just stupid.

what is so special about the zones? Do they have giant bottles around them to keep those icky emissions out?

the whole concept makes negative sense from an environmental point of view. Rather Orwellian to even consider defending it.