This is theoretical for now and cost prohibitive but... If I were to want to use this motor: http://store-en.tmotor.com/goods.php?id=891 on a go kart... what controller would I use first of all. Would I need the esc? I'm unfamiliar with the drone world. Any other problems I wold run into? Seems like a pretty badass build idea to me.
Large drone motor for go kart
- Thread starter skyeg3
- Start date
A problem with RC motors is the lack of torque, they focus on RPM primarily, if it cant provide enough torque you will need to gear it or slap a torque converter on it otherwise it will have trouble moving and will likely overheat.
Look at a Motenergy motor, they are far cheaper and more suited to the task
Look at a Motenergy motor, they are far cheaper and more suited to the task
The only "definite" info I found about a motor on that link is:
There's no specifications about it at all, no physical size, kV (though there's some numbers with KV after them, no way of knowing if that *is* the kV), current capability, power ratings, max RPM, etc.
However, in general these are meant for thousands (or more) of RPM, which means you need quite a lot of reduction between it and your wheel--possibly multiple stages, depending on the wheel RPM you're after.
Often enough, the reduction mechanism adds enough cost, weight, volume, and/or inefficiency that it's cheaper and easier to go with larger lower-RPM motors.
(complete quote of entire page is below my post)
There's no specifications about it at all, no physical size, kV (though there's some numbers with KV after them, no way of knowing if that *is* the kV), current capability, power ratings, max RPM, etc.
However, in general these are meant for thousands (or more) of RPM, which means you need quite a lot of reduction between it and your wheel--possibly multiple stages, depending on the wheel RPM you're after.
Often enough, the reduction mechanism adds enough cost, weight, volume, and/or inefficiency that it's cheaper and easier to go with larger lower-RPM motors.
John in CR
100 TW
On top of no technical specs of significance, they weren't hesitant in the least to put a crazy high price. Spend money on dual battery packs, so you can swap out between races and charge the other. I'd suggest using a proven traction motor instead. The problem with a drone motor is that it's designed to have tremendous continuous air flow over it from the prop, so it will suffer heat problems long before getting to the same power you could when used on a drone.
Hillhater
100 TW
You are losing your touch AW.. :wink:amberwolf said:
There is a tab on that page with full specs, dimensions, performance tests, temps, etc, etc,....quite extensive actually.
And yes its a 29 KV motor that has a 28 kW max rating and 75 Nm of torque.
Its peak of approx 2500 rpm is very low for a kart., requiring almost a 1:1 drive ratio..( most karts run 3:1.- 6:1 ratio depending on the track.
There are 2 other smaller motors linked , different kv, also with full specs .
http://store-en.tmotor.com/goods.php?id=891
There's no tabs or any other info available on the page I get when I visit that link. Only what I quoted there, plus some pics of that motor and a bunch of unrelated stuff not part of the motor.
That isn't a clickable link on the page I get when I visit the link. It's just a word on the page. Why, I don't know--maybe it's written such that it's incompatible with my browser, but either way, I can't access that information, and has nothing to do with senility.
You might want to consider things like that before calling names.
Or even better, you might instead actually place all the relevant information and specifications about something you want to ask about *in your actual post*, so that anyone that can see the post can see the information.
Then you can get help from anyone with knowledge about the topic, evne if they can't access the site linked to.
You might want to consider things like that before calling names.
Or even better, you might instead actually place all the relevant information and specifications about something you want to ask about *in your actual post*, so that anyone that can see the post can see the information.
Then you can get help from anyone with knowledge about the topic, evne if they can't access the site linked to.
John in CR
100 TW
skyeg3 said:
Senile...LOL! You're the one who fell for a load of horseshilt. My hubmotors would make better drone motors despite the extra weight. For the only listing for power those scammers show input power, and then they were stupid enough to show torque, rpm, and temp info, because that info exposes how bad that motor is. Power = Nm of torque X rpm X 0.1047 . An easy bit of number crunching shows why the motor runs at those temp levels and low power compared to the max power they claim, despite being in a strong flow of air for cooling from the propeller. That's because the best efficiency that motor could manage even swinging the light prop is just 84%. They tried to hide the poor efficiency by redefining efficiency as grams per watt of input.
In comparison, at those torque and rpm levels my hubmotor would see a relatively easy load and run at over 94% efficiency. Loading mine down with a bigger prop to require 100Nm of torque would put it right at peak efficiency of almost 96% at the well over 100V required to turn it at that rpm. Whine and cry foul all you want about the over double my motor weighs, and you'd be forgetting about the extra battery weight running that motor would require. Plus the far greater risk of failure running those high temps.
The motor has a nice low winding resistance, so it's low efficiency at cruising rpm must be due to running at too high a voltage. The slot/pole count is too high, probably combined with cheap laminating steel. Drop the voltage to 50V or so and the efficiency should go up to more useful levels and end up with about a 7-10kw motor... For that larcenous price, no thanks!
Senile my A$$ !
A propeller is a mass, as is the air it has to move. How specifically they measure the torque doing that I don't know.
But they probably measure it using a more conventional method, of some sort of dynamometer, or a load-lever like Justin LE used in some testing.
But they probably measure it using a more conventional method, of some sort of dynamometer, or a load-lever like Justin LE used in some testing.
Hillhater
100 TW
Torque can either be measured directly as AW says, using a dynomometer of various forms,...skyeg3 said:
....or it can be calculated as john said, from the voltage, current, rpm, measurements...
Use the Volt and Amp measurements to find the motor power (Watts)
Divide the number of watts by 746 to get the horse power rating of the electrical motor....
..divide the watts by 746 to get the equivalent horsepower .
Multiply the horsepower by 5,252 using a calculator.
Divide the answer by the motor's rpm to get the measurement of the torque in pound-feet.
If needed, convert to Nm by multiplying the lbft by 1.36.
Bluefang
10 kW
Kelly controllers KLS range would be good assuming they can match the high E-rpm of the motors if you want them quiet. Otherwise the KHB range would be better for price, will have a loud whine to the motor usually.
Seriously tho, that price is frocked. Try https://frchobby.en.alibaba.com/?spm=a2700.details.cordpanyb.1.2a5e2c9a2vnlgf
They sell on Aliexpress. Found them when i was looking for a dual conter-rotating propeller setup. Nice stuff and cheap HUGE propellers. They are missing the 1.8m one to work with the dual prop system tho.
Seriously tho, that price is frocked. Try https://frchobby.en.alibaba.com/?spm=a2700.details.cordpanyb.1.2a5e2c9a2vnlgf
They sell on Aliexpress. Found them when i was looking for a dual conter-rotating propeller setup. Nice stuff and cheap HUGE propellers. They are missing the 1.8m one to work with the dual prop system tho.
district9prawn
1 kW
The whopping pole count of 42 means you need a 50000 erpm capable controller just to spin the shaft at 2500 rpm.
If you go through some old posts here you will find some tests on large Hobby King outrunners demonstrating extreme core losses at high speed. No idea if this is the case with T-motor but there is a big efficiency price to pay for the high pole count and thin, weight saving rotor iron.
As others have pointed out there are some cheaper proven options for a motor this size.
If you go through some old posts here you will find some tests on large Hobby King outrunners demonstrating extreme core losses at high speed. No idea if this is the case with T-motor but there is a big efficiency price to pay for the high pole count and thin, weight saving rotor iron.
As others have pointed out there are some cheaper proven options for a motor this size.
skyeg3 said:
VESC 75/300
https://www.youtube.com/watch?v=fbK2dcoYS7g
In the vid above the developer says that it can handle a motor with 1µH inductance, which would be similar as if it would drive current through a one foot long wire
, and it should be able to do 100k ERPM in FOC.So it should have no problem driving mentioned motor.
Do you have any special requirements on space or weight?
Because if not then i would agree to everyone else here and take a true EV motor which has hall sensors and a sealed housing as for instance and in terms of peak power more mass is also a good thing.
It is always fun to read about John and his Hubmonster. It is a heavy beast and old (low pole count which needs alot of iron), but it still seems to be one of the best and highest efficient motors we know about these days
Hummina Shadeeba
10 MW
Any leads on threads showing iron losses at speed with a high pole count? I want to use either a 36t or 18t stator. The 36t would do a maximum speed of about 76,000 erpm doing 45 mph with an 8:1 speed reduction. Both stators have .2mm laminations.
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Hummina Shadeeba
10 MW
Where would I get ur motor?
I got a motoped with a jackshaft and can fit maybe an 8:1 reduction and looking for a motor that’s appropriate. Im looking for a motor with maybe a diameter between 100 and 140 with less than 36 teeth.
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@Hummina Shadeeba I don't know if this fits your requirements but if I was going to use an outrunner motor like that, about the only large one I'd go for is the 80100 (Brushless DC motor 80100 130KV 7000W for Electric Bike | Electric Skateboard | Go cart). It's the largest one that is commonly used on EVs and there is loads of info you can find on it and builds using it. Any other large outrunner will have unknown performance with our applications. That doesn't mean any given motor wouldn't work, it just would be much more risky. Also, most other/larger motors have very awkward shapes for EV applications: great for a paramotor spinning a prop, but terrible for fitting into a bike or emoto.
Hummina Shadeeba
10 MW
I said I’m looking for a motor but really it needs to be a hub motor so as to fit mid-drive on a motoped frame. It needs to be around 40kv as will do 5000 rpm with 126v and like 8:1 gear reduction. Even if a hub motor were 40kv I think the iron losses would be huge and really I’m looking for a stator with fewer teeth to make a hub motor.
where did u get the stator you used in your hub?
I’m trying to find a few toothed stator in the 100 to 120mm diameter range
I’ve had more leads on getting a stator. Here’s a freak with only 9 teeth and 120mm diameter. But why would that be more advantageous than even 12 teeth? I imagine it will run very rough and require big magnets and heavy rotor.
And will likely get this 110mm diameter x 60mm tall with 24 teeth and .2mm lams from here. Not cheap though and will be like 250$ with shipping but this place has lots of options and you can buy one.
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