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

[florkk]

Anyone have maybe some diagram circuit for KT kuteng sine controller?

 

[geofft]

Anyone have maybe some diagram circuit for KT kuteng sine controller?

https://opensourceebikefirmware.bit...S-Kuteng_EBike_motor_controller_schematic.pdf

 

[florkk]

Anyone have maybe some diagram circuit for KT kuteng sine controller?

https://opensourceebikefirmware.bit...S-Kuteng_EBike_motor_controller_schematic.pdf

thank you very much. i have problem and maybe someone know how to solve it. i damaged two kt controllers, one 48v 22A and one 48v 45A 18fet. i build battery pack 15s, with max voltage of 61.5v. Since i use this pack with cheap no name china controller and work great, but i want switch to sine wave, and i upgraded motor. so i have 15s with max 61.5V, caps inside both controller are 63v. first controller worked for 30km, i connect it to battery when i have about 57v, then i charge baterry and after full charge (61,5V) controller is damaged, so i think it happends, and i buy new one with more fet (18fet) and do the same, i make about 50km with about 60-61V, everything was ok till i charge battery to 61.5V RIght now i have two controllers both damaged the same. it power up, communicate with lcd, everything seems working, but when you press throttle nothing happend, is show no error, but whell dont spin. But when you lift wheel and turn it backward, and it still turning slowly back and then press throttle everything work, it speeds up to max speed, when i press brake and give dummy load, it take 30A i can add and back throttle and its slows and speed , but if they motor slows too much, again i cant do nothing. when i stop and turn wheel again backwards and press throttle again it works. btw battery is still 61V.for sure motor is 100% works since i connect no name controller and it works flawless. what can be damaged ? iits looks like it dont wanna start, like missing one phase, or maybe controller dont see hall? but when i disconnect cable i get error about sensor position fault.

 

[geofft]

Anyone have maybe some diagram circuit for KT kuteng sine controller?

https://opensourceebikefirmware.bit...S-Kuteng_EBike_motor_controller_schematic.pdf

thank you very much. i have problem and maybe someone know how to solve it.

I've no experience with running KT controllers at elevated voltages but I'm guessing that the higher voltages you are using are eventually killing the mosfets. I would suggest you reduce your battery to 14s, or maybe look for some 'better' (higher voltage rating) mosfets if you want to continue with 15s. That's just guesswork though, like I said, I'm no expert :wink:

This thread is really about using the open source firmware, you may get more response if you open a new thread for your problem...

 

[BalorNG]

I'm building a low power 'nema 23' drive - mostly because I'm lazy and it has good gearbox options as compared to a typical RC drive, and rated 180w is more then enough to me.
https://www.aliexpress.com/item/32797544178.html
Will a cheap KT controller, or similar chinese e-bike controller work with such a system? I'm working on a tight budget.
7s 24v battery. 13T to 50T on cranks nets me about 100 RPM which is close to my preferred cadence, but it seems that high motor RPMs don't play nice with typical ebike controllers?

 

[bushido]

as far I know, there is no 18FET KT controller. I have the 72V 40A 12FET KT controller from BMSBattery. I think its the most you can get

The first post of this thread implies via picture and title that there at least used to be up to probably at least 24FET versions, though they may not be available anymore.

I've not spent much time at it, but I have had a hard time even finding *any* controllers that I can be *certain* are KT and that have the full current sensors, etc., much less in an 18FET version (which is what I really wanted to find to try this out on my trike).

In case you still need a bigger controller, i found some 18 MOSFET versions

https://s.click.aliexpress.com/e/B7ao9Irt

https://s.click.aliexpress.com/e/WvYkbgqP

https://s.click.aliexpress.com/e/L2yeXDLW3

 

[SlowCo]

And another supplier: https://nl.aliexpress.com/item/4000...hweb0_0,searchweb201602_10,searchweb201603_55

 

[Jatem]

No, this is not a "mechanical" problem, it is absolutely exactly a software problem. Or, perhaps, hardware problems (signal filtering, interference) of the KT controllers themselves.

OK, but it can't be a software problem. I have a buck converter for supplying the head- and rearlights on my bike. Even if the battery is not installed at all and the controller is switched off, the resonaces appear when the lights are switched on. The direct drive motor is working as a generator via the body diodes of the mosfets in this case. So it can't be a matter of PWM or commutation.

This leaves only a hardware problem as the cause of the resonances.
Capacity and inductivity may be in an unfavourable relation.

regards
stancecoke

Is the resonance an issue on both square wave and sine wave versions (could I remove the phase b current sensor to solve the fork judder)?

 

[Valopallo]

How to properly test and measure the correct phase current/battery current ratio to achieve the best performance?

 

[stancecoke]

could I remove the phase b current sensor to solve the fork judder

The current sensor has no influence on the resonance issue...

How to properly test and measure the correct phase current/battery current ratio

The phase current limit is only needed during the very first milliseconds at startup (or at blocked wheel), so I think there is no high potential to optimize the performance.

regards
stancecoke

 

[Jatem]

It's a mecanical problem, you can try to increase/decrease the tension of the spokes, but that might just shift the resonance range...

No, this is not a "mechanical" problem, it is absolutely exactly a software problem. Or, perhaps, hardware problems (signal filtering, interference) of the KT controllers themselves.
I tested the original KT firmware (sine and square version) on 7 different gear (rear ) motors - Bafang, Mxus, and Shengyi. They all had the same problem - the resonances and vibrations of the bike frame and equipment of the bike at a speed of 5-8 km / h, and at a speed of 11-13 km / h. Exactly the same problem with open source firmware. Which is a bit strange.
BTW - Mxus XF15R has good mechanics and an absolute lack of even the slightest vibrations and resonances on a cheap "trapezoid" chinese DMHC controller (I quoted the link above). My other motors also work smoothly without vibration. All this is easy to check - just take another (not KT) controller and check the operation of the motors. Vibration will not be
All this is very sad.
P.S. My KT controllers s have 25 kOhm resistors, instead of "standard" 2.2-2.5 kOhm between + 5V and the signal output of the hall sensors(open collectors). Perhaps - the problem is this, the signals are too "dirty" - the pulses from the motor windings can distort the signals from the hall sensors....

Is there a list of motors that works well with the kt controller, without any resonance?

 

[Valopallo]

If my twin controller/motor setup (2xs06s) pulls max 25A from the battery and I cannot find suitable (fit inside the battery case) bms for my battery, is it ok to bypass bms and discharge without bms? Can the firmware be trusted to shut down properly? If I just let the controllers shut down power from the motors when minimum voltage limit is reached how to be on the safe side and what to adjust from the firmware? I would still balance charge the battery with my 20A bms attached. The cells are up to 8A peak discharge current per cell and the pack is 10s4p. Should it work?

 

[stancecoke]

what to adjust from the firmware?

Just set the under-/ overvoltage limits in the java tool according to your needs, see the wiki:

Undervoltage: Undervoltage cutoff value. Calculation: Value in volts times (256/Battery Voltage Calibration). example: 34.3V * (256/70) = 125

Overvoltage: Overvoltage cutoff value during Regeneration. Calculation: Value in volts times (256/Battery Voltage Calibration). example: 54.0V * (256/70) = 203

regards
stancecoke

 

[Valopallo]

Should the BluOSEC show 15A at the screen when full throttle is applied and the wheel is blocked from turning? Does it ever get to the S06S maximum of 15A? If it should go there mine shows only 11.9A? Obviously then something is wrong here. Either my controller is not delivering the full power or my settings are wrong so that it reads the current the wrong way. I'm running S06S, DD rear motor and 36V 10,4Ah battery with 15A BMS. Here's a picture of my OSEC parameter settings. Does everything look properly configured here?

 

[stancecoke]

With a blocked motor, the phase current limitation will be active. You could check the control state, to be sure.

Use the brake of the bike to keep the speed at e.g. 10 km/h with full throttle, then you will see full amps. If not, you have to check your throttle settings throttle_min and throttle_max.

regards
stancecoke

 

[Nexter]

Hello, i have buy a KT 36 controller (48 V 500/1000 W / 9 Mosfet) and on my controller i have à Bluetooth controller
The bluetooth controller is directly integrated

https://i.ibb.co/N1qkkdw/IMG-20191122-091745.jpg
https://i.ibb.co/3htLN3q/IMG-20191122-091803.jpg

My question is : Are the wires used to connect the Bluetooth controller soldered directly to the correct location on the controller to flash the fimware?

If yes, is there a way to know the order (without disassembling) for the connection with the stlink?

 

[Valopallo]

With a blocked motor, the phase current limitation will be active. You could check the control state, to be sure.

Use the brake of the bike to keep the speed at e.g. 10 km/h with full throttle, then you will see full amps. If not, you have to check your throttle settings throttle_min and throttle_max.

regards
stancecoke

Thank you. Throttle min was too high and throttle max was too high. Now I know at least that I'm using all the current/power I can get. This tip should go to faq!

 

[Valopallo]

If I want more power to S06S, can I just replace my 36V battery to 48V(52V) and change the undervoltage limit from OSEC? Anything else I need to consider before doing this? Specs at the signature.

 

[stancecoke]

If I want more power

Do you want more torque uphill or more max speed? Higher voltage only helps for max speed. For more torque, you need more phase current. A 12Fet Controller would be better in this case.

soldered directly to the correct location on the controller to flash the fimware

The controller can't be flashed via UART. You have to solder the four wires to the SWIM-Interface and have to use a STLink V2 for flashing.

regards
stancecoke

 

[xyrus]

I converted a bird zero electric scooter for personal use with this firmware. It runs great, almost as good as the original controller. Has more than enough torque and runs silent and smooth from standstill to full throtle. It was trial and error , and I have made mistakes.

First controller I bought popped all the FETS when I had entered a wrong number in battery current limit and forgot to connect the hall sensors.

Second controller runs great, but it was a pain to find the correct motor angle, wiki specifies start with 0 if unsure. Turns out 213 was a better start point. With angle at 213 the motor jerked when switching over to 360 interpolation. After lowering it to 190 degree it is perfect.

I would like to know how I can tune the angle to the best setting, I assume the blueosec app can provide that info?

And what is the best way to tune the correction angle? I left it at default of 127, what can I expect when this value is changed? More torque, more speed, smoothness?

If anybody is interested I can post pictures of the scooter and my config used. Let me know!

 

[qwerkus]

And what is the best way to tune the correction angle? I left it at default of 127, what can I expect when this value is changed? More torque, more speed, smoothness?

I believe xyle's phone app displays angle correction. Never tried it myself though.

 

[kgff]

Is it possible via firmware to modify the c5 parameter to have higher current/amps, instead of doing a shunt mod?
I have this sensorless controller

36V/48V 500W 9Mosfets 20A Brushless DC Torque Simulation Square Wave Controller

Thanks

 

[stancecoke]

Is it possible via firmware to modify the c5 parameter to have higher current/amps

Yes for sensored systems, No for sensorless systems, the firmware doesn't support sensorless control.

regards
stancecoke

 

[kgff]

Is it possible via firmware to modify the c5 parameter to have higher current/amps

Yes for sensored systems, No for sensorless systems, the firmware doesn't support sensorless control.

regards
stancecoke

Is it because no one has written firmware for this specific controller, or because of technical reasons?

Does anyone know what's the shunt's resistance of this controller:
KT36/48ZWSRMH-20A 500W 9Mosfets 20A
http://www.pswpower.com/ven.php?cargo.2016-3f-3vm4
www.pswpower.com/ures/cargo/2016/3f-3vm4/2018-5t-hhj576t.jpg

 

[stancecoke]

Is it because no one has written firmware for this specific controller, or because of technical reasons?

You would have to implement 6 step (block) commutation. Casainho had done it in one of his very early commits.

regards
stancecoke