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Discussion Starter #1 (Edited)
Hey I was wondering, does anybody know anything about this motor.

It is on the Kelly controller webpage. States it works with a 15" Buick wheel, has disk brakes and is good for 160kph.http://kellycontroller.com/car-hub-motor-72v-7kw-p-711.html

According to the website, it is good for 72 volts and the controller they suggest pairing with it is good for 400 amps for 1 minute and 200 amps continuously.
Should be good for 38 horsepower for 1 minute if I did my math right.
 

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

According to the website, it is good for 72 volts and the controller they suggest pairing with it is good for 400 amps for 1 minute and 200 amps continuously.
Should be good for 38 horsepower for 1 minute if I did my math right.
Those look like about 18 AWG phase leads, maybe 16. What'd you think? 200 Amps???? Motor spec says 7 kW. I'm thinking maybe 1.5 kW continuous, about 2 hp. But it fits a Buick wheel :confused:
 

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Discussion Starter #4
Yes I know, it is confusing to say the least. Here is a kit that they sell. For 799 dollars if it works it might work for a low weight reverse trike.








96V/120V Dual Car Hub Motor Kit

Click to enlarge

Click to enlarge

Price: $3,899.00


Weight : 166.00 lbs
In stock

Provide free disc brake.

The top speed can arrive at 160km/hr with 96V system.

The kit can work for 96V Lead Acid Batteries or 96V Lithium Batteries.
Please note the kit can work with 120V Lead Acid Batteries, but with 120V Lithium Batteries it may report overvoltage fault.


For 96V System:
KBL12401I(120V 400A Regen)*2
The assembly*1
Car Hub Motor(12-inch)*2
F9607-96V/7A Charger (110VAC Input)*1
Throttle*1
PC RS232 cable*1
USB to RS232 Converter*1
Control box*1
Kelly 96Volt Charge Meter*1
Ampere meter*1

Can do regenerative braking.
Best for car.
Can upgrade to HWC4B Series 96V/12A smart charger with $199.
Please note charger input voltage, 110VAC or 220VAC.
110VAC Input: F9607-96V/7A Charger
220VAC Input: F9607-96V/7A Charger


Can upgrade to 120V System with paying price difference $200.
Upgrade the following items:
HWC4B Series 120V/8A Charger (110VAC Input)*1
Kelly 120Volt Charge Meter*1
 

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Having destroyed and ripped apart a 6kw hub motor (on my lithium evd.) Let me explain the weakness of these motors.

If you look closely you will see all the wiring going into the axle of the hub. At that point is where the wires melt together (on the cheaper chinese hub motors I worked with.) There is just no good way to cool the wires at that point. I melted my hall sensor wiring together at that point with 700 lbs (bike and 2 riders) going up hill at 40mph in 80F weather. Its a fairly easy fix. One must disasemble the motor and replace the wiring with something much higher rated (insulation) than what is there. But ultimately (unless you shut down the motor when it gets hot) it may happen again and again.

I would love to get hub motors it would simplify any conversion but it looks like they all have this weekness. However, Jack R is getting a set from Chry for a smartcar conversion. So perhaps we will see better quality at work and the problem will be solved.

The above motor looks like the one that a place here in Ann arbor uses for their scooter. They replace the hall sensor wires with high temp ones before they even put it on the bike. That takes care of the problem but their bikes are 700lbs with 2 riders and the bike itself. Not 2000 lbs.

There is no reason aside from cooling that a hub motor wouldnt work in your application as long as you understand its failure mode and its for a light weight car. Acceleration however will be marginal with 2 of them now if you did 4...

But ultimately a mars or D&D even would work for light weight cars and an altrex controller. But it really depends on your application.
 

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Discussion Starter #6
Thanks for the input. I think that the best thing to do would be to use a small motor separate from the wheel in case the motor needs to be made bigger. It looks like a wonderful idea from a packaging perspective, but when you tell me of the problems inherent in the design it looks less appealing.
 

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I would like to know more on your thoughts on this hub motor.
I'm toying with the idea of using these to power a Toyota Rav4 conversion.

I do agree with dexion on the cooling aspect of the cables. this is a particular concern of mine as i live in Australia where the summers can be good and hot.

knowing that my car might be approximately 1200kg [2650 pounds] I'm now wondering if my thought on the use of these motors might be a little optimistic. I was toying with buying 4 of them for my car to keep the whole AWD system going.

I'm still in research mode on my plans so I'm looking for the best information sources i can find.
 

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I looked at their test curve data and I think there is something wrong with the readings - or the motor itself.



I added the column with the product of volts and amps which should equal watts, but it's a bit off. However what really stands out is the very low efficiency at low torque output. There are fixed losses of more than 1000W at all loads at nominal RPM. I'm not that familiar with BLDCs but using a 2HP 3 phase motor, the total power used by the DC-DC converter, the VFD, and the motor itself, is about 5 amps at 24V or 120 watts. For a 7kW 10HP motor it should be no more than 5 times that, or 600W. ;)

I realize that it may be an unusual condition to run the motor at 1300 RPM under such low torque conditions, but even the best efficiency of about 83% is not impressive. And $800 seems a lot to pay for a 10HP motor. :rolleyes:
 

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It seems like many have tried high powered hub motors, and to date, all have failed. The problem is, everyone who's tried it seems to simply abandon it without giving the reason, so people/companies keep trying. I have to ask. For what. If it's such an issue keep it inboard and connect it to the wheel with an axle.

One theory I've heard is that the motor bearings simply can't take that kind of load, but, like I've said, all that have tried and failed have been curiously quiet about why. So no one, but those that have tried it, seem to know the actual answer.
 

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I will agree with you that the price is high.
I am so new to the whole EV conversion goal that i don't have a full understanding of what you just said.

all i can really work out is that because there are numbers that don't add up there may be some over optimistic claims made by the kelly company regarding these motors regarding their use up to and including 160km/h [even i think that figure is a dream from this motor]. I just want to have the car as a way of getting around and going shopping/work and still be able to use it as a semi family car on a weekend or for putting a MTB bike on the roof and going for a ride in the mountains. [refer to my post in the conversion forum, http://www.diyelectriccar.com/forums/showthread.php/planning-toyota-rav4-aca20r-short-wheelbase-76422.html

the hard part is that i would like to try and convert a short wheelbase Rav4 to a EV and keep the AWD system. the idea of a hub motor seemed logical. and the idea of efficiency of the motors has yet to really enter my thinking process.

but if there are concerns with these motors it might be best to look at a more conventional EV conversion.
 

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The maximum torque of the hub motor is 78 N-m or 57 lb-ft. If the tire is 24" diameter the amount of force it can exert is 57 lb. Assume you have four of these motors you will have a force of 228 lb. If your vehicle is 2280 lb, it would be just barely enough for a 10% grade.

The speed is determined by the circumference of the tire, about 6.3 feet, so at 1300 RPM that's 8190 ft/min or 93 MPH. So 160 kM/hr is believable. But you really need more torque.

[edit] I thought these motors were designed to connect to the wheel through a CV joint. But that was the WEEL motor. If that's the case you don't need a hub motor.

The "hubcap motor" project from Turquoise is interesting. I also had an idea for a bolt-on hybrid conversion kit, but adding the weight (and size) of a motor on the outside of the wheel may adversely affect the driving characteristics.

Good luck! ;)
 

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Cheers.
The Rav4 is about 2600 pounds [i think, it might be less as i can't confirm the figures]. with this figure in mind the grade is now a good thinking point.

might be worth looking for a new plan of action regarding transmission conversion list. who knows, it might be worth looking into your idea of preserving the CV joints and attaching a motor to each of them. who knows.

thanks for your help.
 

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Without a transmission your going to need more torque, which = more $. I don't think the hub motors can withstand the constant 'bumps' in the road or rain to be reliable. There is also unsprung weight to consider. I'd stick with the transmission and AWD and bolt one motor on. Unless you have the resources and time, maybe you'll find the solution? Good luck.
 

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I agree.
its time to get technical and work out the best electric motor to buy and find/pay someone to make a mounting plate and adaptors for my Rav4. it will let me keep a mechanical reverse gear and potentially have enough grunt to get up hills.

i will need to look at adapting the conversion by gdirwin to suit my car and local conditions. both cars are more or less the same. its just his was the full size Rav4 and i have the short wheelbase.

just need to think about the coupling and the touque convertor.

I was thinking about the rain and the unsprung weight earlier today. I agree with the idea. I still want to have some degree of ruggedness to the car.
aww well back to plan A.
 

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The most powerful (claimed) hub motor I have found is the Keguang KG315. They claim 20kw and 380nm, 250v and 1800rpm.

Edit: here is link: http://www.evmotor.net/kg/eng/ProductShow.asp?ID=95

Making the giant assumption it actually works as advertised, I don't see how to mount it to a regular car spindle since they are all male (outies). What am I missing here? Has anybody got this to mount up?

The other issue is the need for multiple motors and controllers. That kinda defeats any price/simplicity advantage.

If it could be done though, the additional weight and space freed up by ditching the tranny/drivelines is HUGE. Think of all that battery space...

Cheers :)
 

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I don't see how to mount it to a regular car spindle since they are all male (outies). What am I missing here? Has anybody got this to mount up?
I'd like to know as well. The cars I worked on in my lifetime have solid (not hollow) drive shafts at the front hub and solid spindles at the rear wheels. There wouldn't be place to route the wires.

It looks like they mount the motor right on the brake rotor, which would make the wheel poke. Teenagers seem to enjoy this style - I think it looks goofy.

As someone else mentioned, these wires are way too small to power a RAV-4 for example, even at the four wheels.
 

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I agree.
its time to get technical and work out the best electric motor to buy and find/pay someone to make a mounting plate and adaptors for my Rav4. it will let me keep a mechanical reverse gear and potentially have enough grunt to get up hills.

i will need to look at adapting the conversion by gdirwin to suit my car and local conditions. both cars are more or less the same. its just his was the full size Rav4 and i have the short wheelbase.

just need to think about the coupling and the touque convertor.

I was thinking about the rain and the unsprung weight earlier today. I agree with the idea. I still want to have some degree of ruggedness to the car.
aww well back to plan A.
Nothing wrong with thinking outside the box, you may very well have something. I just hate to see ppl get part way into a build and bail. Although that's where I get good prices on components. :)
 

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Ruckus,
thank you for helping with this additional product. it didn't come up in any of my searches.
it looks like a good piece of kit. its something that i would consider. I also guessing its EV weight considerations would be minimised by having 4 of these in the car.


mk4gti,
your right about mounting them in a car but I'm guessing something could be fabricated. If I'm not wrong i seem to remember my dads land cruiser having a shaft housing that was hollow. at a guess this would be a place to install the motors into and still provide a place to route the wires.?
its not possible in my rav4 and it still leaves a question as to how to mount the fronts so they steer but I'm guessing something could be made.

I have seen these hubs as a style in mock-ups on various vehicles in shows and I've always thought there is great promise in these hubs to convert the existing fleet or to provide for better storage of the power source.

--

the thought as to how much weight would be removed from the car with all its ICE and transmission removed is a good thought but if 140kg of motors are installed + controlling gear + mechanical/electrical augmentation of existing control mechanisms + batteries I'm wondering is the advantage is neutralised.

don't get me wrong, this is project of mine is to be very carefully thought out and will be my version of building a lotus 7. [now theres a thought - an EV lotus 7 replica powered in the rear by 2 in hub motors on a "live axel" suspension setup].
 

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Well, the idea of hub motors is a good one, but it would be best used on an 'experimental' platform which is light-weight and small. I wouldn't go getting all fired up and try to convert a daily driver suv to hub motors without a test vehicle.

I am not one to follow the mainstream, but hub motors are the lunatic fringe.

Please be careful.
 
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