KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW)

[stancecoke]

Can you confirm, that the blue FETs are on high side? Drain connected to the battery + rail?
The voltage on low side is strange, I guess there will be defective parts on the PCB... But without a scope it's difficult to debug. At this point I can't help any further.

 

[Angrubean]

Can you confirm, that the blue FETs are on high side? Drain connected to the battery + rail?

Yes, the middle leg (drain) on the blue FETs is connected to the positive rail on the PCB.

The voltage on low side is strange, I guess there will be defective parts on the PCB... But without a scope it's difficult to debug. At this point I can't help any further.

It's fine, I'm grateful for your cooperation and help I recieved. I'll try to get my hands on a scope and/or poke around on the PCB in hope to find any clues to what could be wrong.

 

[LongRangeRider]

This OpenSource firmware/embedded software runs on the BMSBattery S/Kunteng KT motor controllers.
The main advantages of this controllers are:
1. sine wave/"FOC": motors run silent and very efficient
2. cheap: starting at 20€
3. widely available: many online shops sell them and ship to worldwide
4. various sizes e powers: from 0.25kW up to 5kW (72V, 70A, 24 mosfets)
5. supports LCD and Bluetooth mobile app
6. schematic available: important if you want to mod/hack, repair or even build your own controller
7. generic brushless motor controller: can work as a generic brushless motor controller and be commanded by an Arduino or other similar external microcontroller board. This feature is only available when using our OpenSource firmware.

The main advantages of our OpenSource firmware/embedded software are:
1. sine wave/"FOC" max efficiency: motors run silent and very efficient and is possible to tune a parameter to get the best efficiency possible for a specific motor
2. flexible and OpenSource: more than customization, any feature for some specific need can be easily implemented and for free (no need to pay any commercial license)
3. throttle, PAS and torque sensor: all of them are supported
4. LCD3 and LCD5: all of them are supported
5. regen/ebrake: works very well on the direct drive motors
6. motor torque controller/motor current controller
7. motor speed controller
8. generic brushless motor controller: using the UART connection (the same that is used for the LCD and Bluetooth module), this controller can work as a generic brushless motor controller. Can be commanded by an Arduino or other similar external microcontroller board.

Please read the project status, how to install the firmware, history and motivation on his website: C#ROME-B Home

I am looking to add a torque sensor BB to my e-bike.

I would like to continue using my cadence sensor and throttle. However, in the software, there doesn't seem to be an option to run all three at once.

Am I missing something...

Thank you for any shared insights.

 

[szkuba]

You can try this fork GitHub - stancecoke/BMSBattery_S_controllers_firmware at Torque_from_X4

 

[Voron]

Hey guys!
Does anybody know if this firmware will work on any of Kunteng's integrated controllers?

This is the only message that rises this question.

KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW)

I am still very interested in trying the fw, especially the cruise control would be nice to have though. The app looks nice, I hope I can get an old phone working and try to use it on. I have to get the parts to be able to program before I can get much furter though. I know there was some talk...

endless-sphere.com

I've also partially read through this thread and it seems like there's problems with 9fets. Would I then be better off with a 6fet? Or is it worth it to take the risk for extra power and buy a 9fet instead?

Thanks in advance!

 

[amberwolf]

All the 9FET does is add a second FET to part of each phase bridge--it doesn't actually increase phase current like going up to 12FET would, just enables the controller to handle part of the commutation cycle better, which can increase power output a little bit without blowing up the controller. But since the other part of each phase bridge is still only 1 FET, that still limits the phase current to whatever that FET can handle.

So using a 12FET will be better than a 6FET or 9FET, if you really need the extra power.

To determine if you need this, I recommend using the ebikes.ca motor simulator to guesstimate your power needs to do the job your systme needs to do for you, under the specific riding conditions you have. It takes some learning and experimenting to use, but it is more helpful than getting parts that may not do the job you need done, and having to replace them. It will also help you make sure the battery you may already have can supply the current required as well, without being stressed or damaged, and that it has enough Wh to give the range at the higher power usage, as it can help you guesstimate the Wh/mile of that.

 

[Voron]

To determine if you need this, I recommend using the ebikes.ca motor simulator to guesstimate your power needs to do the job your systme needs to do for you, under the specific riding conditions you have. It takes some learning and experimenting to use, but it is more helpful than getting parts that may not do the job you need done, and

Great! I didn't know that such a website existed.

Does this mean that the 6 FET and 9 FET controllers have a close or same phase current limit? And would it then be fine to use an integrated 6 or 9 FET with this firmware? Like the ones attached.

 

[amberwolf]

I don't know if the "integrated" boards are the same as the standalone ones. If "integrated" means they are designed for OEMs to use in their bikes, or in bottle batteries, etc., they could have different original FW, or even different hardware designs that won't respond the same to FW not specifically written to handle those differences. There may be info on that in this thread or in the Github repositories or the main OSFW website, etc.

I would guess that the phase current would have to be about the same for 6 and 9 (and 12/15) FET controllers, because the single FET on half of each bridge would be the limiting bottleneck, no matter how many FETs are in the other half.

 

[Voron]

I don't know if the "integrated" boards are the same as the standalone ones. If "integrated" means they are designed for OEMs to use in their bikes, or in bottle batteries, etc., they could have different original FW, or even different hardware designs that won't respond the same to FW not specifically written to handle those differences. There may be info on that in this thread or in the Github repositories or the main OSFW website, etc.

Interesting, I'll be searching for further info from other sources. There was only two posts about these type of controllers in this thread so I doubt that I could find anything more here.

because the single FET on half of each bridge would be the limiting bottleneck, no matter how many FETs are in the other half

Yeah, that's what I've been thinking about. Could probably dig up something in this thread.

Thank you!

 

[Sturmey]

I would guess that the phase current would have to be about the same for 6 and 9 (and 12/15) FET controllers, because the single FET on half of each bridge would be the limiting bottleneck, no matter how many FETs are in the other half.

Dont forget that extra 'freewheeling/flyback' current over and above battery current is generated caused by collapse of motors magnetic field with PWM and this circulates through (usually I think) the lower set of 3 fets through the body diodes. Doubling up on these 3 FETs as say with a 9 FET controller seems to work well in this situation, especially with a high rpm motor running slower and current controlled by pwm rather than back emf.

 

[amberwolf]

Sure, but that's not phase current from the system producing torque driving the motor forward, which is what was being referred to as "phase current" in previous posts (AFAIK).

 

[Sturmey]

Sure, but that's not phase current from the system producing torque driving the motor forward, which is what was being referred to as "phase current" in previous posts (AFAIK).

It is indeed phase current. It circulates through the motor. Freewheeling/flyback current adds to the battery current and increases torque. As far as I know, at any moment, Phase Current=Battery Current + Flyback Current.
Anyhow that my understanding. I have a 9 fet controller and it works great.

 

[amberwolf]

Ah, ok. I have seen no difference between 6 and 9 FET versions of controllers here on my systems, other than that the 9FET didn't get as hot especially in regen braking as the 6FET, but it has been a long time since they were big enough to move my cargo bikes, so things may have changed. I don't think I have anything nowadays I could use as a comparison test set. (whatever I have left around here would be different brands / models and so not directly comparable that way)

 

[Voron]

Anyhow that my understanding. I have a 9 fet controller and it works great.

With the firmware? Then why are people having problems with them? Do you have any clues? Or is it just that some versions are more compatible than others?

 

[Sturmey]

With the firmware? Then why are people having problems with them? Do you have any clues? Or is it just that some versions are more compatible than others?

Sorry, it does not have custom firmware.

 

[Vbruun]

Hey guys!
Does anybody know if this firmware will work on any of Kunteng's integrated controllers?

This is the only message that rises this question.

KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW)

I am still very interested in trying the fw, especially the cruise control would be nice to have though. The app looks nice, I hope I can get an old phone working and try to use it on. I have to get the parts to be able to program before I can get much furter though. I know there was some talk...

endless-sphere.com

I've also partially read through this thread and it seems like there's problems with 9fets. Would I then be better off with a 6fet? Or is it worth it to take the risk for extra power and buy a 9fet instead?

Thanks in advance!

Yeah i've used it. It works great. Best fork is Andrea-104 or torque from x4. They're more stable.

 

[Voron]

Yeah i've used it. It works great. Best fork is Andrea-104 or torque from x4. They're more stable.

On what controllers? Integrated "hailong" or 9FETs?

 

[Vbruun]

On what controllers? Integrated "hailong" or 9FETs?

Actually both.

 

[Voron]

Actually both.

That's great news! Then I'll order an integrated 9FET and hope for compatible hardware I've long searched for a flexible solution for my ebike and now have seem to found one!

I suppose you've tried it on a 9FET integrated like the one attached?
Which branch did you use? And do you have any "proven" parameters, like phase current?

Thanks!

 

[Vbruun]

I bought mine from topbikekit.

I used the 22a battery limit like the original and twice that for phase amps. It was fine and didn't get hot. I don't think the stock plug can take more current than that, but I don't know the limit of the controller.

 

[Voron]

I bought mine from topbikekit.

I used the 22a battery limit like the original and twice that for phase amps. It was fine and didn't get hot. I don't think the stock plug can take more current than that, but I don't know the limit of the controller.

Thanks! Then I'll buy a 9FET integrated from the same shop and use the same settings for the phase and battery current. Hopefully I won't experience issues like the other 9FETs.

It seems that the Andrea branch was merged with Master. So I suppose that Master should be stable now.

 

[Vbruun]

Good luck. I have had great luck with the firmware. Big thanks to stancecoke, casainho, Andrea_104 and all the other contributors.

 

[KarsusKerman]

Hi, I have used this firmware for years with no issue,
But now I have upgraded the controller and bought a torque sensor to use. And I can't connect with bluosec the app crashes when trying to connect, the diagnostic tool works.
And the motor "pulses" when trying to throttle up.
And on lcd mode no info is displayed.

Can someone help ?
Thanks

 

[amberwolf]

What specifically does "upgraded the controller" mean, completely, for your situation?

 

[KarsusKerman]

What specifically does "upgraded the controller" mean, completely, for your situation?

Sorry I meant I have bought a 12 mosfet and used to have a 9 mosfet that burned.
Did everything in the new controller, problem I can't connect with the bluosec it crashes few seconds after trying to connect, don't know how to fix that