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30kw Hub motors for EV?

68K views 62 replies 14 participants last post by  G-man 
#1 ·
http://www.ev-propulsion.com/motorcycle-hub-motors.html

Each motor is 10kw cont. and 30kw peak...

Could these be retrofitted into a car rim? could they be paired? side-by-side to create 60kw car wheels?

Generally speaking 15-20kw should be enough to cruise at freeway speeds (70mph)

Imagine 2 in each wheel, 8 motors, 240kw peak, AWD and AWD-regen braking, more room for batteries, 1300each = 10K$ price tag for motors alone...

What do you think of this setup? A bit over the top eh?

8 motors = $10,400 (4 motor pairs, 1 pair for each wheel)
8 controllers = $8,000 (I am not sure if this could be simplified)
37 400AH TS cells = $16,300 (48kwh, if 15kwh = 70mph, then 100%DoD = 224miles, pack weighs 1000lbs)
BMS = 2,300 (not sure but seems reasonable)

Total $37,000 (w/o donor)

your thoughts, comments, suggestions, ideas?
 
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#16 ·
I don't know if this one does or not.... but be careful with absolute statements like that.

Here is a in-wheel hub motor that gets ~98% efficiency... and it was made back in 1999... there might be some progress in getting prices down in the last 10 years... but as others have posted... efficiency is not flat... it changes depending on the specifics of the conditions.
 
#3 ·
I really liked the idea of doing the same thing but using them inboard, for example close to where the diff would be. It all looked good but the rpms when used with the Kelly controller, if I remember correctly where about 1500 so if you do your maths, it did not make for a great top speed.
 
#5 ·
The motor is designed for motorcycles as stated on the web site and is 10KW continous not 30 KW
Also the motor is 90 plus eff at 75% of max speed. Huge amount of work was done to minimize eddy currents at speed to improve eff. This is a custom design that cost EnerTrac a huge amount of money to develop.

EnerTrac Corp. has several test motorcycles all are welcome to test ride and judge the performance and range for oneself.
We are located in Farmingdale, NY

EnerTrac and EV propulsion are working on a electric differential version of the motor for small cars. We'll have something to show in a few weeks.

Anyway please don't bad mouth a product for a application its not intended for. When we come out with the car version it will be with a working car, then you can judge if the product meets your needs. We are also working on a controller to match to the motor for a greatly reduced cost compared with what is now available

http://www.doingitall.net/EnerTrac



Mark
 
#11 ·
Mark, this DIY forum's existence relied/relies on people being innovative using products made for different applications (forklift DC motors) in DIY EVs...No one is bad mouthing your product(s).

I look forward to your car hub motor or differential motor or whatever you guys come out with.:)


 
#12 ·
frodus...it doesnt matter...if constant or peak eff...

a hubmotor is always under 90%...

and we all know that the motor from mark is not a super hightec motor...

it is a bigger X5000 and thats it...

mark you say "huge amount of money to develop"...let us know what you have done to the motor design, thats cost so much and gets the Eff over 90%
 
#14 ·
hey, frodus...well i dont like statements like "the motor has 90% + Eff" without proveing it...

maybe it is possible to get a hubmotor(with BLDC design) over 90%...but you will have to use hightec materials...

in low rpms you have alot of copper losses...

i would like to post e Eff-picture...but my webspace is down
 
#17 ·
I know its not the designed method of use, but if the website claims that EACH motor should support...495lbs (fully loaded weight)...

These voltage and current results were obtained using a 325
pound motorcycle with a 170 pound rider on a flat road with
little to no headwind your results will vary depending on
motorcycle, rider weight, and conditions.
....Then EIGHT motors should be able to support 3,960lbs

I think the battery pack weighed in at 1100lbs for 224 mile range (100% DoD)

~1100lbs Batteries
~500lbs for 8 Motors
~200lbs for 4 controllers (one per each wheel-motor-pair)
~100lbs Charger + Extras
~100lbs Misc.

Total = ~2000lbs

1960lbs Remaining!!;)
 
#18 ·
I know its not the designed method of use, but if the website claims that EACH motor should support...495lbs (fully loaded weight)...



....Then EIGHT motors should be able to support 3,960lbs

I think the battery pack weighed in at 1100lbs for 224 mile range (100% DoD)

~1100lbs Batteries
~500lbs for 8 Motors
~200lbs for 4 controllers (one per each wheel-motor-pair)
~100lbs Charger + Extras
~100lbs Misc.

Total = ~2000lbs

1960lbs Remaining!!;)
Seems the Curtis AC Controllers have a dual drive functionality and I wondering if one of there controllers could be used for two Enertrac motors that are not mechanically linked. This would seem unusual for an AC controller. Anyone with any understanding of this?
Quote from Curtis website;
• Dual-Drive functionality is standard, allowing correct
control of vehicles such as 3-wheel counterbalance trucks or
other applications featuring twin traction motors. This function
ensures smooth and safe operation, minimal tire wear and
correct load sharing between the traction motors at all times.
 
#19 ·
No, still need 2 controllers, it supports talking of the two together to correct for slip when going around a turn.

2 motors, unless their shafts are welded together/mechanically linked 100%, need 3phases each. Since there's 2 sets of 3-phase, you'd need 2 controllers. Period.
 
#24 ·
i realy dont wanna talk bad about marks motor...just want to stick to the truth...

@IamIan
you should be carefull WHAT you are comparing...
the CSIRO is a axial flux HIGHTEC motor...no iron inside...

marks motor is a "normal" radial flux hubmotor...BLDC...with 2-3kg of iron inside
 
#28 ·
@IamIan
you should be carefull WHAT you are comparing...
the CSIRO is a axial flux HIGHTEC motor...no iron inside...

marks motor is a "normal" radial flux hubmotor...BLDC...with 2-3kg of iron inside
I wasn't comparing anything.

I said I don't know what the efficiency is or the curve would be for this particular motor.

I was only writing a word of caution about the use of such absolute statements ... this goes for wheel motors , hub motors as much as anything... the CSIRO was just a specific example of a flaw in such absolute statements.

this motors DONT have a Eff of 92%...NO WAY

No hubmotors get Eff over 90%...
I don't know if this one does or not.... but be careful with absolute statements like that.

Here is a in-wheel hub motor that gets ~98% efficiency... and it was made back in 1999... there might be some progress in getting prices down in the last 10 years... but as others have posted... efficiency is not flat... it changes depending on the specifics of the conditions.
 
#52 ·
I know you've asked me this question a few times and I don't want to be overly optimistic with the answer. Mike and I work on this project between paying customers and late at night so its tough to pin a exact release time.

Here is my time line
1) next high voltage/speed bench test and solve any alignment vibration problems
2) Bench test the suspension travel as motors are running
3) Finalize the half shaft modifications
4) Purchase and Test dual controllers
5) Mount in the car, the test car is already electric
6) Road test, make detailed thermal measurements add forced cooling if needed this will greatly depend if there is any airflow over the motors when mounted under the car.
7) Move forward with preliminary sales and begin user documentation

Any problems along this path can add weeks to the design cycle but as it stands now, three to five weeks to in car testing five to eight weeks to preliminary sales. The motors themselves are in stock at my factory/shop

Mark
 
#54 · (Edited)
So since the standard motor costs about 1300$ and the recommended Kelly controller costs 700$ (thanks roughrider) then with 4 motors, if you wanted 120kw peak, would approximately cost 8,000$ not including the cost of EVpropulsion assembling the subframe for the motors which isn't free and was some good ol fashioned r&d. So my speculation is 10K$ for 120kw peak system with regen, thats 161hp....should perform well considering you save and extra 1-200lbs of the transmission...
 
#56 ·
I don't see it working that way.

First, a decent transaxle can easily be found under 100lbs, so there isn't a big savings there.

These motors have no cooling fans, so putting four of them together under the hood is going to require some blower setup at a minimum.

There are diminishing returns beyond using two of these motors. An AC31 or AC50 with a small transaxle is likely a better compromise than 4 of these hub motors.

TomA
 
#58 ·
One AC50 would put out about 1250 ft lbs of torque to the wheels in 1st gear on my setup, 0 to 25mph would probably go to the AC50. And unless peak power of these hub motors is matched to the top speed of the vehicle, the AC50 could even have a higher top speed, with proper gearing.

I'd like to see the torque curves vs speed on these motors, peak hp really doesn't tell you much.
 
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