motor rating and controller

[John 987]

Hello Experts

I have an existing 16 inch-wheel hub motor. The controller and battery were damaged and I ordered a new set but not from original supplier.

I am not sure what motor rating is the new controller designed for. My new battery is rated at 67v max.

After assembling the motor to the controller and battery pack, I turned on the unicycle and I lifted the wheel before powering it up. The gyro is working and the wheel can rotate fore-aft.

The only problem it seems is that when transitioning from one direction of rotation to the opposite direction (by tilting the machine), the motor seems to Jerk quite severely. i was terrified by this weird reaction.

I tried switching the order of the hall sensor wires but it got worse eg. the motor could not rotate or went berserk with strong sudden wheel spins.

So, I stuck to the initial hall sensor wiring which allowed the motor to rotate fore-aft.

My suspicion of what could be wrong :

1. The motor may be rated higher than what the controller is designed / meant for.

The controller may be meant for a smaller 14 inch hub motor. The existing motor is 16 inch and could be rated higher wattage. Maybe the coil ratings or impedance is not suitable? I have no clue. Just guessing. Does my suspicion make any sense? Is the jerking due to incompatible motor ?

Or could it be that :

1. The gyro and accelerometer need to be re-tuned ? the controller need to re-learn with this motor?

Lifting the wheel in the air above ground and turning it on, the machine is able to rotate fore-aft and seems rather balanced horizontally.

Kindly could you help give me some clues as to what could be the cause?

 

Thank you for reading.

Have a nice day.

 

Best regards

John

 

 

 

 

 

 

 

 

 

 

 

 

 

[Gimlet]

I believe that it is important that the motor and controler are matched and if you bought a controler that wasn't specifically marked as being for a 16" then odds are that it's for a 14" as generic wheels are predominantly 14s and 16 inchers are relatively uncommon.

[MetricUSA]

So what happen when you didn't lifted it up in air, when on ground? Any wheel will jerk in the air....

[John 987]

Hi MetricUSA

its as jerky when on the ground.

How can we identify the validation points on the circuit board?

For example, is there any component that is linked to the 2 points such that I can trace to confirm the points are validation points (2 pins for short-cicuiting)?

Thanks.

regards

John

 

[John 987]

Subsequent to posting my earlier reply, I decided to short the 2 pins to the right of the hall sensor wires on the controller card. The photo is found at this url :

http://ai.taobao.com/auction/edetail.htm?e=f948pNOXeLq6k0Or%2B%2BH4tKPZQhIMjHU%2BnnDOe2U0TNmLltG5xFicObalFqTViQTOxN35oEuRTJeELZiKZQKWJM92PLG%2BMM1niSB4tCRFmUVQdRqM5%2BtvqG3abJM7sDg2Psue8g%2FwSqB8V10JQoYFyA%3D%3D&ptype=100011&rType=1&from=goldenlink&clk1=bed787310adb48054d3e59de45f825b1&upsid=bed787310adb48054d3e59de45f825b1

I was surprised that there was no perceived calibration being done as in the front and then back rotations initiated by the controller during such an operation.

Any ideas why this is so? Is a 16 inch motor really incompatible with this controller?

 

 

[Jay Barnett]

From what the guys tell me on the Russian forum you can use a 16 inch controller with a 14 inch wheel, and they have done so. Calibration is essential! on my board there are two wires with a male and female plastic connection on the ends that you clip together to initiate the calibration mode. On other boards you have to find the two pins that do it...
The other thing is that if there is jerking then you likely havnt got the 3 power leads correct. In most models the first yellow wire is always yellow, but often (as with mine) the green and blue wires need to be swapped around. Hall sensors always seems to be easy and just from left to right hooked up in sequence but for the three power cables you may need to try all 6 combinations to find one that doesnt jerk at all.
Then once you that far if you still need to calibrate then find the calibration pins!

[Gimlet]

Subsequent to posting my earlier reply, I decided to short the 2 pins to the right of the hall sensor wires on the controller card. The photo is found at this url :

http://ai.taobao.com/auction/edetail.htm?e=f948pNOXeLq6k0Or%2B%2BH4tKPZQhIMjHU%2BnnDOe2U0TNmLltG5xFicObalFqTViQTOxN35oEuRTJeELZiKZQKWJM92PLG%2BMM1niSB4tCRFmUVQdRqM5%2BtvqG3abJM7sDg2Psue8g%2FwSqB8V10JQoYFyA%3D%3D&ptype=100011&rType=1&from=goldenlink&clk1=bed787310adb48054d3e59de45f825b1&upsid=bed787310adb48054d3e59de45f825b1

I was surprised that there was no perceived calibration being done as in the front and then back rotations initiated by the controller during such an operation.

Any ideas why this is so? Is a 16 inch motor really incompatible with this controller?

 

 

When you shorted the terminals did you have the wheel standing upright and turn on the wheel with no reaction?

[John 987]

On 8/14/2015 at 0:59 AM, Gimlet said:

I believe that it is important that the motor and controler are matched and if you bought a controler that wasn't specifically marked as being for a 16" then odds are that it's for a 14" as generic wheels are predominantly 14s and 16 inchers are relatively uncommon.

Thanks dude. I wonder how to discern if the controller is for 16 or 14 inch? By the number of large capacitors?

On 8/21/2015 at 6:41 AM, Jay Barnett said:

From what the guys tell me on the Russian forum you can use a 16 inch controller with a 14 inch wheel, and they have done so. Calibration is essential! on my board there are two wires with a male and female plastic connection on the ends that you clip together to initiate the calibration mode. On other boards you have to find the two pins that do it...
The other thing is that if there is jerking then you likely havnt got the 3 power leads correct. In most models the first yellow wire is always yellow, but often (as with mine) the green and blue wires need to be swapped around. Hall sensors always seems to be easy and just from left to right hooked up in sequence but for the three power cables you may need to try all 6 combinations to find one that doesnt jerk at all.
Then once you that far if you still need to calibrate then find the calibration pins!

You are right dude! I had tried swapping the 3 phase wires before. Did not work. So, its probably the controller as per advice given here.

 

On 8/22/2015 at 5:28 PM, Gimlet said:

When you shorted the terminals did you have the wheel standing upright and turn on the wheel with no reaction?

The beast was too violent for me to dare to try calibrating it. The jerking is too violent and potentially deadly.

[electric_vehicle_lover]

@John 987 I also get the same problems when trying to use different controllers for 14 motors. Seems the firmware changes from motor to motor.

The best bet is to make our own firmware which I am working on and is not far, I hope :-)

[lizardmech]

The ST BLDC firmware for the STM32F103 doesn't appear to support auto motor detection and configuration. You have to manually input things like number of pole pairs etc. So different motor configurations will likely prevent it working even if it's the same size wheel.

[SheilaCaba]

Hi everyone..i am new to this forum and by profession i am an engineer. I want to say that  if there is jerking then you likely have not got the 3 power leads correct. In most models the first yellow wire is always yellow, but often the green and blue wires need to be swapped around. Hall sensors always seems to be easy and just from left to right hooked up in sequence but for the three power cables you may need to try all 6 combinations to find one that does not jerk at all.
 

circuit board fabrication