2x 7 KW HUB motor for car

[Bazaki]

I like HUB motors since it is easy to install on a bike.

http://kellycontroller.com/car-hub-motor-72v-7kw-p-711.html

Would it be realistic to install 2 of these motors to a car of about 1000 kg ?

This also is the only " strong" hub motor for a car that I can find on the internet.

I would like to do some experiments with an old car and just install 2 of these HUB motors and see if it is possible to drive arround at speeds of max 70km/h

They are rated at 7 kw, but I think they also can handle 15 kw for short moments, so 2 of them is 30 KW. Should be enough to ride with daily traffic.

I can't find many projects on the internet with HUB motors on normal cars.

Any thoughts ?

 

[Kin]

I would suggest that it's only borderline possible. You're not asking for too high parameters (43mph max). So you want to make sure that's really the only max speed you need.

DIYElectriccar and EValbum should give you an idea of what other people before you have done.


Acceleration would be slow, though, even though you're only geared to 70kmh. A think 7k is the lowend for powerful motorcycle build, which might be something like 300kg. You have two 7k motors, but the car you suggest will be 1000kg.


Probably you want to wait for more expert responses, but in the meantime might be able to check out diyeelctriccar and Evalbum

 

[Bazaki]

Thank you, I found another hub motor 15kw and 40kw peak performance, but now I enter a territory that is new to me. It runs with a sevcon controller, and I thought it would be like an ebike hub motor, just connect 3 phase wires and some hall sensors and it runs. But those sevcon controllers needs to be configured really well to run the motor.

Sounds like fun, but I don't have any experience with this.

And to run 2x hub motor I also need 2x sevcon controller so it won't be cheap.

Would a car travel ok with one wheel drive ?

 

[Kin]

Out of my league of experience, maybe someone else can respond. Sevcon controllers require complicated programming, however, according to what I've read of Luke's sevcon.


What exactly are you going for in this project? It sounds like you want to get "sort of" into the electric car business, but that you acknowledge it's quite complicated to get really far into it. I'm concerned that you might end up having what amounts to a still rather expensive project, but without the benefit of going all out into the project. You also might underestimate, thinking that a hubmotor project will be easy. It still can be rather complicated.

So laying out why exactly you want this project might be helpful for others and yourself. Maybe a cargo-bike /cargo-trike would suit your interests, and be more likeweight/reasonable.

Here's a tiny cool car: http://www.evalbum.com/3390. Yeah, i'd also explore those sites to see what other people have done. There might be some way to search the site's car section on google and add the term "hubmotor" or "hub"

 

[Dauntless]

Would a car travel ok with one wheel drive ?

In the classic style, it all depends on what you think is "Okay." Durning WWII, with the car companies building planes and other war materials, a magazine published an article with two designs for building a 3 wheel 5hp buggy out of wood. Decades later, Dad would always get a chuckle out of seeing that one of those was still running around our town; he told me of the dilemma that led to it being built. Good enough for 70 years ago doesn't mean good enough for today. Then again, there's some pretty rum cars out there that ain't really good enough.

So I can hook you up with intereting ideas from magazines. I don't know if the link is just down or if they'll put the plans back up.

http://www.finkbuilt.com/blog/suburba-car-diy-3-wheeler/

Here's a four wheeler designed with just one wheel drive. Someone built one that sold for some serious amount of money more than 4 decades later.

http://blog.modernmechanix.com/2006/08/16/build-your-own-mahogany-sports-car/#more

Mainly, it's all a matter of what you are ready to come up with. (4 page thread of 3 wheers. http://advrider.com/forums/showthread.php?t=507507)

 

[Bazaki]

Thanks for thinking with me !

I would like to drive a 4 wheel car of today, not a 3 wheeler.

For example a VW Golf of 2003, keep the original engine in the front, to run on gasoline when the battery is empty, install a 15 KW motor ( 40 KW peak ) hub motor at the rear, and 4 kwh of A123 in the back.
But only one HUB motor probably won't work, and what about 2 Hubmotors, what to do with steering, probably it will steer very bad since each motor has the same speed.

The Sevcon programming is totally new to me and I am afraid I get stuck at this part, I still don't exactly understand why it has to be so complex.
2 of them makes this also pretty expensive.

Anonther idea:

What about installing an electric motor to the driving shaft of a car ? And let it run with some kind of bendix like a startmotor will do.

So put the gearbox in neutral and run on electric, so the whole car can stay original.....impossible?....doable ?

 

[Kin]

I don't think you have gotten back about the problem of why you're doing this with a hubmotor. It's a pretty important consideration to make, and an important thing to understand in the design process.

As far as I'm aware, you're going to need your sevcon professionally programmed. So, overall, I don't think this is likely to be cheaper or easier than a traditional single-motor design. If it will be cheaper, it will be at certain design costs, and that's what you're going to need to work out.


If you drive a single hubmotor with considerable power, I believe you'll have a moment that causes drifting to the right. Which, assuming you compensate for that, will reduce efficiency.

 

[Bazaki]

About the Sevcon in combination with this motor
http://www.evmotor.net/kg/eng/ProductShow.asp?ID=99

Well, al lot of work has been done with this combination and the motor actually runs a small car, so it is possible to make this work.
But it still needs more programming to run it at 100%. but Sevon is able to help.

Maybe someone can explain why this is such a complex thing ?
Why can't the motor just spin arround like our ebike hub motors? I mean the stuff is bigger and stronger and is able to take more Volt/Amp. I don't understand why some motors need advanced programming.

A totally new idea:

I'm not sure if something like this will work but maybe this is a better idea.
The goal is to convert a car to electric but still able run on the original ICE engine.

 

[Dauntless]

Well, hey, that's why I kept squeezin' in a lil' time to read some of this during one busy week, too much interesting to just miss everything.

Gee, I'm thinking that on ANY front wheel drive car you could add that to the back and still have the original drivetrain intact. That looks like some sort of motor/differential/CBjoint arrangement, though can't say that for sure. (I really don't think it's considered a HUB motor.) MECHANICALLY that seems easy enough. but how you turn on the electric motor but leave the engine off until you need it becomes a tougher issue.

Get ready to write some serious software. You wouldn't happen to have a programming degree, would you?

 

[Bazaki]

http://www.go-ev.com/

This company is selling what I was looking for, Inline Driveshaft motor.

http://www.evalbum.com/2098

And with their EMIS system you connectot it to your cars OBD port and it will communicate with the controller.

It seems to work really well, but I think the original ICE motor has be on stationary, so you have all functions working and the Electric motor " supports" your original ICE.

I whish they had a system to run on the Electric motor only and keep the original ICE off.

 

[Dauntless]

http://www.go-ev.com/

This company is selling what I was looking for, Inline Driveshaft motor.

Huh? Is that for 4 wheel drive???? I think you only get the motor from them, you come up with the halfshafts yourself. I hate to state this as a fact but I feel certain you're only intended to hook the yoke end up to maybe the differential and the other end should be locked to something that won't move, NOT a splined shaft attached to a transmission.

And with their EMIS system you connectot it to your cars OBD port and it will communicate with the controller.

It seems to work really well, but I think the original ICE motor has be on stationary, so you have all functions working and the Electric motor " supports" your original ICE.

I whish they had a system to run on the Electric motor only and keep the original ICE off.

"On stationary?" Is that your own terminology? I think you're reading more into it than the posting is telling. Note that BMW is listed as "Under Construction" and might have been abandoned. This is an approach that will be limited to a rear wheel drive, not many cheap cars out there for you to work with doing that. Dang, is that motor strong enough to endure that? When whatever 250hp engine is trying to move the 3,000 pound car, the chain will only be as strong as it's weakest link. The housing and the shaft both getting torqued at both ends, scary thought.

 

[Bazaki]

I think I had it wrong, no stationary, this electric motor just supports the original engine so you get a better MPG. Nothing wrong with that but I'm looking for another solution.