Looking for a brushless powerful motor for my e-scooter

[bigbore]

I have a registered mini e-scooter that I use to go around in my little towm.
In my country the electric scooters must be registered as the gas scooters so I have a license plate, I must pay the assurance, ride it with the helmet and have a driving licence.
My previous e-scooter traveled 3000Km (1864 miles) and I've been using it from 2010.
Now I have bought a new model.
In the picture the yellow/black is the old one and the white/black is the new one.

The new one is currently modified with an industrial brushed Amer MP80S/2 motor made in Italy and a lipo battery made with 8 lipo packs Haiyin 5000mAh in a configuration 10S4P that is nominal 37V 20Ah. The MP80S/2 motor is from my older scooter.

The controller that drives the motor is the YK42-3
Now I'm looking for a brushless motor and a brushless controller with dimensions similar to the YK42-3 controller 12.5cm × 9.0cm × 4.6cm

Worth to try this motor?

http://e-bike-diffusion.com/index.php?module=produit&prd_id=508&url_retour=http%253A%252F%252Fe-bike-diffusion.com%253A80%252Findex.php%253Fmodule%253Dcategorie%2526code_cat%253D24%2526page_start_num%253D1

 

[ARod1993]

Depends; if your main concern is the new motor being able to fit into roughly the same form factor and bolt pattern as the old, then go for it. If you're looking for maximum power for a given weight ratio, then you might want to take a look at this post for information on selecting a drivetrain and an electrical system for a small to mid-sized escooter.

 

[bigbore]

Thank you for the link, that’s a very informative thread.
My present plan is the following:
I’m going to try the motor I linked before with a controller that could be used with a RC type motor too.
Then if the power delivered from that motor is not enough I will look for a RC type motor like the Turnigy SK3 6374-149kV.
I would mount the controller inside the chassis as I have now so the Kelly KBS48121X 130A peak and 55A continuous with dimensions 114 x 78 x 41 mm would be good.
I also would stay with my present lipo battery setup 37V 20Ah.
From the measurements I have from a wattmeter installed between battery and controller my present data are: 2700W (70A @39V) during acceleration and 1200W (30A @39V) cruising at the speed of 25mph
Can the Kelly KBS48121X be used with the motor I linked before?
From the manual I read "Hall Sensor Type: 60 degree and 120 degree"; if I don't know what type Hall Sensors are installed on that motor can I just try 60 degree and then if it doesn't work 120 degree? Or it would hurts to the controller?
What do you think about the motor I would try? Will it deliver roughly 1500W (40A @39V) continuous without overheating?

 

[ARod1993]

Thank you for the link, that’s a very informative thread.
My present plan is the following:
I’m going to try the motor I linked before with a controller that could be used with a RC type motor too.
Then if the power delivered from that motor is not enough I will look for a RC type motor like the Turnigy SK3 6374-149kV.
I would mount the controller inside the chassis as I have now so the Kelly KBS48121X 130A peak and 55A continuous with dimensions 114 x 78 x 41 mm would be good.
I also would stay with my present lipo battery setup 37V 20Ah.
From the measurements I have from a wattmeter installed between battery and controller my present data are: 2700W (70A @39V) during acceleration and 1200W (30A @39V) cruising at the speed of 25mph
Can the Kelly KBS48121X be used with the motor I linked before?
From the manual I read "Hall Sensor Type: 60 degree and 120 degree"; if I don't know what type Hall Sensors are installed on that motor can I just try 60 degree and then if it doesn't work 120 degree? Or it would hurts to the controller?
What do you think about the motor I would try? Will it deliver roughly 1500W (40A @39V) continuous without overheating?

Current- and voltage-wise, the Kelly KBS48121X will do you just fine for the motor you're trying to buy; also, does that motor have Hall sensors already installed? If not, then you're going to either need to take the motor apart and install them yourself (which can be a fairly labor-intensive process), attempt to mount them externally (which may be difficult to do properly), or use a different controller; Kelly controllers can't run without Hall sensors. For timing, you'll want 120 degrees most likely (at least that's what I use on RC motors); getting the timing wrong shouldn't kill the controller, but it'll make the motor run slow, rough, and with minimal torque. I don't know enough about that specific kind of motor to tell you for sure, but I'd be surprised if it couldn't do nameplate.

 

[bigbore]

Current- and voltage-wise, the Kelly KBS48121X will do you just fine for the motor you're trying to buy; also, does that motor have Hall sensors already installed? If not, then you're going to either need to take the motor apart and install them yourself (which can be a fairly labor-intensive process), attempt to mount them externally (which may be difficult to do properly), or use a different controller; Kelly controllers can't run without Hall sensors. For timing, you'll want 120 degrees most likely (at least that's what I use on RC motors); getting the timing wrong shouldn't kill the controller, but it'll make the motor run slow, rough, and with minimal torque. I don't know enough about that specific kind of motor to tell you for sure, but I'd be surprised if it couldn't do nameplate.

From the picture I guess the motor is a sensored type but to be sure I wrote an e-mail to them cause I'm not going to mount the sensors on the motor I will buy.

Is the white connector in the picture the one for the hall sensors?

 

[amberwolf]

From the picture I guess the motor is a sensored type but to be sure I wrote an e-mail to them cause I'm not going to mount the sensors on the motor I will buy.

Doesn't matter if a motor is sensored or not, you can use it with a sensorless controller if you want. Some sensored motors may work better with a sensored controller, though, and often enough there can be issues with starting up from a complete stop (especially pointed up a hill) with sensorless.

Is the white connector in the picture the one for the hall sensors?

Doesn't look like it has enough wires--is probably a thermal sensor (2 wires?)

 

[bigbore]

I ordered the motor and the Kelly controller KBS48121X.
The motor is coming from the french shop of the same seller:
http://electra-bike.fr/index.php?module=produit&prd_id=169

And he wrote me in e-mail that the motor is 120° sensored type.
In the picture in the french shop and I can see 5 little wires with colors red, orange, green, blu and black.
On the Kelly controller manual I can see were the black, orange, blu and green wires should go and I hope the red one on the motor can be connected to "yellow hall-a" to the controller.

Does it make any sense?

Edit:
On the controller manual I can see I need to connect +5V, is it the red wire on the motor?
Then I guess black wire on the motor will go to "Black RTN" on the controller
Then the blu on the motor will go to the "Blu Hall-C" to the controller
The green on the motor will go to the "Green Hall-B" to the controller
The orange on the motor will go to the "Yellow Hall-A" to the controller

This second option I think is correct.
Anybody knows if a wrong connection on the red +5V wire could fry the sensors on the motor?

 

[amberwolf]

Remember that colors of wire don't necessarily mean anything at all, unless they actually tell you with labels on them or in a manual which ones are what. Often enough I would guess that they use whatever color wire is laying around at the time, based on what I have seen in some of the cabling on various items I have fixed.

(soemtimes it isn't even all one color--twice I have found wires inside a cable spliced together with one color on one end and a different one on the other, because they probably ran out of one of the colors while making it. I've also had a number of cables for ebrakes and throttles and such that while they use the same color thru the whole cable run, they have a splice in the middle somewhere (not soldered or crimped!) where one of the colors either broke or ran out during the production of the multiwire cable....)


It's possible to damage the halls if you hook up the supply voltage wrong, but probably only if it's backwards. I've had to just randomly guess at a motor color combination before, and I think I tried almost all of them before I found the right one, and it didn't do any apparent damage. So it might be fine, and it might not.

If they follow normal conventions, then +V would be red and -V or GND would be black, but they could literally use any color, so you need to ask them to be sure, if they don't provide any manual.

 

[bigbore]

Remember that colors of wire don't necessarily mean anything at all, unless they actually tell you with labels on them or in a manual which ones are what. Often enough I would guess that they use whatever color wire is laying around at the time, based on what I have seen in some of the cabling on various items I have fixed.

(soemtimes it isn't even all one color--twice I have found wires inside a cable spliced together with one color on one end and a different one on the other, because they probably ran out of one of the colors while making it. I've also had a number of cables for ebrakes and throttles and such that while they use the same color thru the whole cable run, they have a splice in the middle somewhere (not soldered or crimped!) where one of the colors either broke or ran out during the production of the multiwire cable....)


It's possible to damage the halls if you hook up the supply voltage wrong, but probably only if it's backwards. I've had to just randomly guess at a motor color combination before, and I think I tried almost all of them before I found the right one, and it didn't do any apparent damage. So it might be fine, and it might not.

If they follow normal conventions, then +V would be red and -V or GND would be black, but they could literally use any color, so you need to ask them to be sure, if they don't provide any manual.

Thank you very much, I wrote to the seller of the motor about the sensors connection I should do for +5V and GND.

 

[bigbore]

I have received the brushless motor and hooked it to a kelly controller model KBS48121X.
The colors of the sensors wires caming from the motor do not match the color on the controller socket so I changed the positions of the wires from the motor to the socket on the controller until I found out what's the correct position that's controller "blu" wire to motor "green" wire; controller "green" wire to motor "yellow" wire and controller "yellow" wire to motor "blu" wire. The phase wires are wired yellow to yellow, blu to blu and green to green.

The motor reaches the temperature of 49°C (120°F) after running 5 minutes on the bench with out any load on the sprocket at full throttle.
From my knowledge this is not a good starting!
What should I change on the controller to solve this issue?
Could be wrong the number of poles stored in the controller setup and the actual motor poles?
Any other thing I can check?

 

[amberwolf]

It's probably what's called a "false positive". Go to the ES wiki and look up John in CR's method of finding the right phase/hall wire combo; it's the easiest method I've seen that works just about every time from what people have reported back. (it's also all around the forum, but the wiki has less stuff to look thru for it).

 

[John in CR]

Check the no load current from the battery before changing anything. The 2 primary things that are indicators of an incorrect combo are abnormally high no-load current (varies by motor and voltage), and a jittery or noisy start-up when turning the throttle very slowly from a start. If your phase wires are easy to disconnect, and you're worried about a bad combo, simply try the other 5 combinations of phase wires (you can do it with the halls instead with the same result if they're easier to swap). If one of those runs smoother in the other direction then yes you had a false positive, and you'd have to swap to of the set you were keeping static and go back and swap the others to get it going the right way smoothly.

Of course a motor will warm up running on the bench at wide open throttle with no cooling, so I'm not convinced you even have a problem. That's why I suggest measuring first.

I've also noticed that running a motor with the axle vertical warms up the axle, because the bearings are getting a side load and have more friction that way. Mine got warm enough that I thought the bearing was bad, so I took the motor apart and replaced the bearing, only to have it get hot again before I realized what is going on.

BTW, there's an ES Wiki that explains how to determine wiring.

FWIW, it's never even dawned on me to run one of my motors WOT at no load before. I noticed my warm/hot axle after only a minute or so revving it up to loosen up the bearings, something I now regret, since I clamp them in the vice with the axle vertical when bench running.

 

[bigbore]

In my setup the phase wires are bolted to the controller wires with M5 screws and nuts so the easiest way of changing something is to swap the sensors wires and it's what I've done to determine the position I think is the correct one.
As I wrote before the phase wires are wired yellow to yellow, blu to blu and green to green and then I tried all the 6 possibilities with the hall wires and the only one that results in a good starting motor and in the correct direction is the one I described before. When turning the throttle very slowly from a start the motors do not start with a jittery or noisy start-up.

The specs of the motor I'm trying are the following:
BLDC BRUSHLESS DC MOTOR 48V 1500W
Speed 6600 RPM
So I calculated a Kv of 137,5
Then that are the measurements I have with a watt meter wired between the battery pack and the controller.
With a 10S lipo battery and full throttle with no load I measured:
Amp:4; Watt:155; V:39; Rpm (calculated):5362
Motor temp after 5 minutes were 49°C (120°F)

With a 13S lipo battery and full throttle with no load I measured:
Amp:4.8; Watt:246; V:51; Rpm (calculated):7012

Are these data normal for a brushless dc motor?

Until now I have tried the motor in the horizontal position with out any cooling like in the following picture:

Tomorrow I will make a test with a 12V PC cooling fan in front of the motor like in the following picture and will repeat the test with a 10S lipo battery.

Just for a comparison the brushed Amer MP80S/2 motor I've been currently running on the scooter have the following no load data with a 10S lipo battery:
Amp:2.6; Watt:110; V:41;

 

[vax]

Nice project.
We modifyed similar scooter, with Turnigy SK3 motor and Kelly 50A mini brushless controller. We chose Ping 48V 10Ah battery pack, fits that floor box perfectly.
We tweaked the motor a bit, adding thermocoupler, hall sensor ring and radial fan. After that temperature never exceeded 60 deg.C
Result: 55km/h and superb acceleration.
Testing with 60A model ESC:
[youtube]uKTh47D7rd0[/youtube]

 

[bigbore]

Tomorrow I will make a test with a 12V PC cooling fan in front of the motor like in the following picture and will repeat the test with a 10S lipo battery.

I have repeated the bench test with no load, 10S lipo battery pack and with the cooling fan the temperature after 5 minutes were little lower than before. It was 42°C (107°F).
I think the motor will have some heat problem wen full loaded with 1500W, so I will build an air duct to have some air in the holes of the motor while running on the street.

 

[bigbore]

At the moment I'm ready to build a cover made of carbon fiber and a plate to screw at the opposite side of the motor sprocket, the green square part will be a 12V PC cooling fan and above I will mount a heat sink too.

 

[bigbore]

Update for the project:
Now I'm running the BHT diffusion Brushless motor and the Kelly controller KBS48121X from 400 Km and I have to admit that it provides a good amount of power without overheating.
Here is the scooter:

The data I measured with a Turnigy Wattmeter hooked bettwen the battery and the controller are the following:
With the same transmission ratio 4.9 as the previous brushed Amer MP80S/2 motor, 11T motor sprocket and 54T rear wheel sprocket I have a top speed of 41Km/h with a watt peak of 3300W and it cruise at 1200W and 41Km/h.
Then I tried the other 3 combinations I can try; that are transmission ratio of 4.0(11/44), 3.6(15/54) and 2.93(15/44) and with the last one I have a top speed of 55Km/h with a watt peak of 2950W and it cruise at 2000W and 55Km/h. The highest temperature I measured are 57°C at the motor and 55°C at the controller.
The peak amps I measured is between 80 and 87 Amps, is it normal as I'm using only 38-36 Volts?
Then the only thing I do not like is the way the controller cuts the current as the battery approaches the lower voltage setting. I would like to have a more constant power until low voltage cut off, so I have programmed a lower voltage threshold of 20V and I’m using a LVC board I made myself that is like the one sold by Tppacks some year ago.