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

Electric Motors and Controllers
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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by honya96 » May 06 2018 2:53pm

lqbweb wrote:
May 06 2018 2:24pm
Today I tried again my controller on a real ride. P5 set to 0 and the battery indicator was displaying emtpy, even though the battery was full. So same behavior as with my power supply at home.

Again, when the voltage drops under 30v, it starts blinking. But otherwise it says always empty if P5=0, or always full if P5=5 for instance.

Do you guys think it is a hardware problem or software? Is the battery blinking action controlled by the controller or the lcd firmware?

I don't know what else to try, the PE8 port seem to be getting like 3V, so I think it is fine. I think the software just went crazy. Perhaps it needs a full discharge cycle?
I think its caused by the dc-dc converter. I have it too, but havent tried battery indicator yet.
I am looking at voltage only.

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

Post by geofft » May 06 2018 2:58pm

Hmmm, you don't need to worry about that. But it is binary coding of the signal, like 5 is 101, 3 is 010, etc. Where 1 is 5 volts and 0 0 volts.
Ah...ok, now I understand.
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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by lqbweb » May 06 2018 3:08pm

honya96 wrote:
May 06 2018 2:53pm
lqbweb wrote:
May 06 2018 2:24pm
Today I tried again my controller on a real ride. P5 set to 0 and the battery indicator was displaying emtpy, even though the battery was full. So same behavior as with my power supply at home.

Again, when the voltage drops under 30v, it starts blinking. But otherwise it says always empty if P5=0, or always full if P5=5 for instance.

Do you guys think it is a hardware problem or software? Is the battery blinking action controlled by the controller or the lcd firmware?

I don't know what else to try, the PE8 port seem to be getting like 3V, so I think it is fine. I think the software just went crazy. Perhaps it needs a full discharge cycle?
I think its caused by the dc-dc converter. I have it too, but havent tried battery indicator yet.
I am looking at voltage only.
Why do you think that? which dc dc regulator have you put? Have you tried at least to turn it on?
Thanks!

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

Post by honya96 » May 06 2018 3:12pm

lqbweb wrote:
May 06 2018 3:08pm
Why do you think that? which dc dc regulator have you put? Have you tried at least to turn it on?
Thanks!
I have the one which geofft suggested to you. It works, runs ok, LVC is ok. But I dont remember if it shows battery with stock FW. I just dont look at it.

And now I am running this FW and battery indicator works

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

Post by lqbweb » May 06 2018 3:18pm

ok, I just dont see any possible reason to blame the dc dc regulator. That net is completely independent.
I am tempted to flash this, but I am waiting for a second controller to arrive from China in order to have a backup. I need this controller working.

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

Post by honya96 » May 06 2018 3:21pm

lqbweb wrote:
May 06 2018 3:18pm
ok, I just dont see any possible reason to blame the dc dc regulator. That net is completely independent.
I am tempted to flash this, but I am waiting for a second controller to arrive from China in order to have a backup. I need this controller working.
As a reason to blame it i see that, it was working before.

You can try to put the original back. Its quick switch

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

Post by casainho » May 06 2018 4:04pm

geofft wrote:
May 06 2018 2:58pm
Hmmm, you don't need to worry about that. But it is binary coding of the signal, like 5 is 101, 3 is 010, etc. Where 1 is 5 volts and 0 0 volts.
Ah...ok, now I understand.
There may happen an issue: let's say the right sequence is ok and the motor runs ok, BUT on the backwards direction..... because to run on the contrary direction, that sequence will be the same but on the inverted direction. The thing is that seems that the angle that FOC should be "done" is different for each side.
Well, let's see what you get and then we can think. Please confirm later that you are using the same connections with original and our firmware.
Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

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

Post by lqbweb » May 07 2018 2:48am

honya96 wrote:
May 06 2018 3:21pm
lqbweb wrote:
May 06 2018 3:18pm
ok, I just dont see any possible reason to blame the dc dc regulator. That net is completely independent.
I am tempted to flash this, but I am waiting for a second controller to arrive from China in order to have a backup. I need this controller working.
As a reason to blame it i see that, it was working before.

You can try to put the original back. Its quick switch
ok, this morning I just received my backup controller. Now I can confirm that it is the frocking software, either from the LCD (LCD6) or the controller.

With a new controller, without any mod, it is happening the same. Somehow the battery indication has some sort of memory and autolearning I think. Not even resetting it fixes it.

I will finish up the bike during this week, and go for a full discharge cycle.

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

Post by geofft » May 07 2018 8:01am

casainho wrote:
May 05 2018 2:00pm
geofft wrote:
May 04 2018 1:16pm
Just tried this, things don't seem quite right.
Please try the following process. I wrote it to install firmware instructions and if they are ok to you, I will put online:

Hall sensor connections

With the motor phase wires disconnected (it is recommended to insulate with tape the phase wires) and the hall sensor wires connected to the motor controller, use a multimeter to measure the voltage of each hall sensor wires.

Rotate the wheel slowly by hand in the backward direction and the motor will rotate (if you are using a geared motor, it is the only direction which the motor will rotate).

For the hall sensors to be correctly connected, you must make sure the voltages sequence is the following (and repeats over and over) - if not, you will need to exchange the wires up to get the right sequence:

Position | Blue wire: hall sensor C | Green wire: hall sensor B | Yellow wire: hall sensor A
2 | 0 volts | 5 volts | 0 volts
6 | 5 volts | 5 volts | 0 volts
4 | 5 volts | 0 volts | 0 volts
5 | 5 volts | 0 volts | 5 volts
1 | 0 volts | 0 volts | 5 volts
3 | 0 volts | 5 volts | 5 volts

Phase wires connections

Yellow wire: motor phase A
Green wire: motor phase B
Blue wire: motor phase C

After having hall sensors with the right sequence and with the motor controller turned off, connect the motor controller green wire phase B (middle wire on controller board, being the yellow and blue on the extreme to run the sides) to the motor green wire. Now connect the other wires with the same colors and finally try to run the motor starting with a low throttle value and with a protected lab power supply or battery pack with a BMS. If the motor don't work, makes noise, ask to much current, etc, exchange the yellow and blue wires between them, keeping the green wire - try again to run the motor.
If the previous ways was not ok for running the motor, you can try other motor phases combinations.

Just completed this:-
Hall seq test reduced.jpg
...it wasn't easy to do because with the 13.2:1 reduction on my gear motor the distance between individual steps at the wheel rim is just a few mm and often the residual flux in the motor coils would cause it to 'jump' forward past the required test position. Anyway, in the end I can confirm that my hall sensor sequence is exactly as shown in your list above.

Then played around with motor phase connections, tried all six possible combinations but the only sequence that would run was the 'straight' option (B-B, G-G, Y-Y), all other sequences gave major issues. These 'straight' connections (both hall and motor phase) are the same that I use for the stock controller.

Not sure if that is of any help to you. Although the latest fw (with the revised FOC) gave me the running issues we discussed before, the previous version runs extremely well, the only issue that bothered me was the high controller (not motor..) temperature compared to stock fw, so you are pretty close to getting things right.... :)
Last edited by geofft on May 07 2018 9:25am, edited 1 time in total.
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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by casainho » May 07 2018 8:17am

Thank you Geofft. Great that you tested all the combinations. Was there a combination that motor rotated backwards??

Good to know that the same colors on wires works and my motors also.

If the controller is getting hot, you are getting also lower range, right??
Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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

Post by honya96 » May 07 2018 8:26am

casainho wrote:
May 07 2018 8:17am
Thank you Geofft. Great that you tested all the combinations. Was there a combination that motor rotated backwards??

Good to know that the same colors on wires works and my motors also.

If the controller is getting hot, you are getting also lower range, right??
From my experience there is only one working phase wire combination for each hall combination so from all 36 there is 3 forward and 3 reverse.
I read somewhere that there should be 1 best forward and 1 reverse but for me they all seem to be running well.

Geofft tried only those six from which one is running forward.

I don't understand why are you even trying this now?

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

Post by geofft » May 07 2018 9:00am

casainho wrote:
May 07 2018 8:17am
Thank you Geofft. Great that you tested all the combinations. Was there a combination that motor rotated backwards??

Good to know that the same colors on wires works and my motors also.

If the controller is getting hot, you are getting also lower range, right??
I think one setting after much juddering spun momentarily in reverse, but no setting gave anything like a 'true' reverse. TBH I find it hard to accept that my hall/phase connections are not correct, any changes in these would mean it would not run with the stock fw which surely can't be right?

I think the range is a little reduced compared to stock, but I haven't done a 'normal use' full range check for a while. If I was forced to guess I would say range has suffered maybe 5-10%.
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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by casainho » May 07 2018 11:23am

geofft wrote:
May 07 2018 9:00am
TBH I find it hard to accept that my hall/phase connections are not correct, any changes in these would mean it would not run with the stock fw which surely can't be right?
Well, I develop with my motor and controller. You have a different motor and controller. With your tests I think we did learn more about this subject and I am more confident that this controllers and motors from China use the same wiring between them which is great.

Also I think that procedure to validate the hall sensor connections and phases is now validated.

So back to the issue, if your motor runs but the controller get's hot, maybe is just some small angle adjust... I didn't had chance to do deep testing. And I remember that angle FOC was at +30 degrees from what I was expecting... maybe it is wrong and I need to remove that 30. I am away from home up to the weekend, maybe I will try and ask to you to test, if you don't mind.
Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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

Post by geofft » May 07 2018 12:11pm

casainho wrote:
May 07 2018 11:23am
geofft wrote:
May 07 2018 9:00am
TBH I find it hard to accept that my hall/phase connections are not correct, any changes in these would mean it would not run with the stock fw which surely can't be right?
So back to the issue, if your motor runs but the controller get's hot, maybe is just some small angle adjust... I didn't had chance to do deep testing. And I remember that angle FOC was at +30 degrees from what I was expecting... maybe it is wrong and I need to remove that 30. I am away from home up to the weekend, maybe I will try and ask to you to test, if you don't mind.
No problem, happy to help where I can.. :)
Could MOTOR_ROTOR_OFFSET_ANGLE be relevant to controller temperature? I don't mind experimenting further with this if it may help.

BTW:- For me there is no rush to fix these things, the bike I'm using for this is just a test bike, I have other (BBS02 mid drive) bikes for riding if I need. So take your time... :wink:
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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by lqbweb » May 07 2018 1:10pm

Have you seen guys that for instance the phaserunner has a mode to autotune the motor? You are meant to spin the motor by hand i think while connected to the computer. Is this anything useful for you? You could figure out the sequence and angles maybe?

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

Post by casainho » May 07 2018 1:29pm

[quote=geofft post_id=1378264 time=1525713066 user_id=30257]
No problem, happy to help where I can.. :)
Could MOTOR_ROTOR_OFFSET_ANGLE be relevant to controller temperature? I don't mind experimenting further with this if it may help.

BTW:- For me there is no rush to fix these things, the bike I'm using for this is just a test bike, I have other (BBS02 mid drive) bikes for riding if I need. So take your time... :wink:
[/quote]
[code]// this value of 174 (244 degrees; 170 would be 239 degrees) was found experimentaly
// seems to be about 180 + 60 degrees; were I expected to be 180 degrees
#define MOTOR_ROTOR_ANGLE_FOC (174 + MOTOR_ROTOR_OFFSET_ANGLE)[/code]
Please adjust the "174" value to something between 110 and max of 255 (including the sum of MOTOR_ROTOR_OFFSET_ANGLE).

Note that 20 equals to 30 degrees, 31 to 45 degrees, 42 to 60 degrees. I would say maybe the final value will be some of that round numbers (+ or -): 30, 45, 60 or 90 degrees.

I am away from home this week but I strangely feel well here :-) -- a lot of people using also ebikes here in Tubingen:

[url=https://postimg.cc/image/8kcihucjp/][img]https://s18.postimg.cc/m19h0pmvd/2018-0 ... .53.09.jpg[/img][/url]

[url=https://postimg.cc/image/5dhyy87j9/][img]https://s18.postimg.cc/qae72w5k9/2018-0 ... 7.47-2.jpg[/img][/url]

[url=https://postimg.cc/image/iuexh2f9x/][img]https://s18.postimg.cc/dvrf2jbh5/2018-0 ... .03.10.jpg[/img][/url]
Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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

Post by 1N4001 » May 07 2018 6:31pm

Electric motors have horrible efficiencies at low RPM. This can be seen well on the ebikes.ca simulator. The rest is wasted as heat in the windings.

Do you think it would be a cool idea to optionally parametrically scale the phase current limit with motor rpm? e.g.

(rpm/A)^(1/3) where A=max rpm

Example: A=300rpm -> At very low speeds like 50rpm you only get 55% max phase current, which prevents overheating. At 300rpm you have nominal 100%. A different function might be better suited, this is just for illustration purposes.

One could also set A lower than max rpm to get an extra current boost above A rpm (where efficiency is good)

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

Post by -dg » May 07 2018 8:04pm

1N4001 wrote:
May 07 2018 6:31pm
Electric motors have horrible efficiencies at low RPM. This can be seen well on the ebikes.ca simulator. The rest is wasted as heat in the windings.
This is not correct. If you use the simulator with the setting for a torque throttle you will find that the motors are very efficient across a wide band of rpm.

However, motors have higher losses with higher currents (I^2), which can for typical ebike motors and controllers only occur at low rpm. But as long as the phase current is limited to reasonable values efficiency remains good.
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Re: KT motor controllers -- Flexible OpenSource firmware for BMSBattery S/Kunteng KT motor controllers (0.25kW up to 5kW

Post by casainho » May 07 2018 11:22pm

1N4001 wrote:
May 07 2018 6:31pm
Electric motors have horrible efficiencies at low RPM. This can be seen well on the ebikes.ca simulator. The rest is wasted as heat in the windings.

Do you think it would be a cool idea to optionally parametrically scale the phase current limit with motor rpm? e.g.

(rpm/A)^(1/3) where A=max rpm

Example: A=300rpm -> At very low speeds like 50rpm you only get 55% max phase current, which prevents overheating. At 300rpm you have nominal 100%. A different function might be better suited, this is just for illustration purposes.

One could also set A lower than max rpm to get an extra current boost above A rpm (where efficiency is good)
That is not a priority for me. Also I don't feel the need for that so I am not motivated to do it.

My suggestion is for you to write o the issue tracker as a feature, you can put all the information there so will not be forget over the time and maybe in future it can be implemented.
Developer of the Flexible OpenSource firmware for EBike motor controllers (TSDZ2 and KT) and LCDs (KT-LCD3 and Bafang 850C color LCD).

If you like my work, you can consider making a donation. I am being using the donations to buy needed resources for my developments. My paypal: casainho AT gmail.com.

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

Post by honya96 » May 08 2018 1:50am

1N4001 wrote:
May 07 2018 6:31pm
Electric motors have horrible efficiencies at low RPM. This can be seen well on the ebikes.ca simulator. The rest is wasted as heat in the windings.

Do you think it would be a cool idea to optionally parametrically scale the phase current limit with motor rpm? e.g.

(rpm/A)^(1/3) where A=max rpm

Example: A=300rpm -> At very low speeds like 50rpm you only get 55% max phase current, which prevents overheating. At 300rpm you have nominal 100%. A different function might be better suited, this is just for illustration purposes.

One could also set A lower than max rpm to get an extra current boost above A rpm (where efficiency is good)
Your idea is not correct. It does not work like that.

You use high phase current only at startup, so if you limit it like that, you will have to push the bike to get it moving.

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

Post by 1N4001 » May 08 2018 4:16am

honya96 wrote:
May 08 2018 1:50am
You use high phase current only at startup
Not true, this only applies if you "run out of" battery voltage to keep the current flowing. In a system with sufficiently high battery voltage at full throttle, phase current stays constantly at the current limit. Just look at the motor simulator and compare "motor current" at different speeds.
so if you limit it like that, you will have to push the bike to get it moving.
No, it's a matter of how you set it up.

If before you had a phase current limit of 15A due to excessive heat at low speeds, you could now set it to 20 or 25A. Your low speed current/torque ideally remains unchanged, but your high speed current/torque would be significantly improved, possibly allowing you to reach higher speeds too.
casainho wrote:
May 07 2018 11:22pm
That is not a priority for me. Also I don't feel the need for that so I am not motivated to do it.

My suggestion is for you to write o the issue tracker as a feature, you can put all the information there so will not be forget over the time and maybe in future it can be implemented.
Understandable. I'll do that.

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

Post by honya96 » May 08 2018 5:14am

1N4001 wrote:
May 08 2018 4:16am
honya96 wrote:
May 08 2018 1:50am
You use high phase current only at startup
Not true, this only applies if you "run out of" battery voltage to keep the current flowing. In a system with sufficiently high battery voltage at full throttle, phase current stays constantly at the current limit. Just look at the motor simulator and compare "motor current" at different speeds.
so if you limit it like that, you will have to push the bike to get it moving.
No, it's a matter of how you set it up.

If before you had a phase current limit of 15A due to excessive heat at low speeds, you could now set it to 20 or 25A. Your low speed current/torque ideally remains unchanged, but your high speed current/torque would be significantly improved, possibly allowing you to reach higher speeds too.
casainho wrote:
May 07 2018 11:22pm
That is not a priority for me. Also I don't feel the need for that so I am not motivated to do it.

My suggestion is for you to write o the issue tracker as a feature, you can put all the information there so will not be forget over the time and maybe in future it can be implemented.
Understandable. I'll do that.
Try it on road, not simulator. You will find that it's non-sense.

We all want the oposite of what your idea will offer.

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

Post by 1N4001 » May 08 2018 6:17am

Try it on road, not simulator. You will find that it's non-sense.
Nope. The simulator is pretty good once you understand it. I'm fairly sure your "on the road" system is just limited by battery voltage, hence the confusion.

This is an example system whose max speed is limited by voltage. You see the obvious knee at 25kph, which is the point where the motor is generating so much voltage itself that phase/torque current cannot be kept up. Up until that point it remains pretty much constant (controller current-limiting). The resulting speed is the intersection of red motor power and black load.

Equip this system with a higher voltage battery and you'll get this. Now the max speed is limited by torque. You'll notice it intersects before the knee. The motor could still accelerate further, but the phase current/torque limit needs to be raised for this.


You state you want maximum torque from the start. Understandable.

But there are use cases for intentionally limiting torque at low speeds: Less battery usage, or climbing hills at slow speeds. BionX even offer a mountain mode which does just that, to reduce heat during long climbs.

Another use case would be for owners of torque-limited systems. Keep the start current/torque the same (which is entirely doable), but "boost" it at high RPM, to raise the top speed. The point is to squeeze more power out of the motor under conditions when there is still untapped potential.

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

Post by stancecoke » May 08 2018 8:56am

Concerning regen:
Here is a good explanation how our PWM is working as step-down converter in motor mode and as step-up converter in regen mode.
Here also is described to use the BEMF that belongs to a certain rpm for controlling the regen, like I proposed some posts before :-)....

https://www.roboteq.com/index.php/appli ... en-braking

regards
stancecoke

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

Post by Snickers » May 08 2018 9:58am

casainho wrote:
May 04 2018 8:04am
Snickers wrote:
May 04 2018 7:43am
So, do you think I can be face to magic smoke with my S06S boosted to (60V 55A) ~3KW* used with a direct drive motor?
Maybe you should try with a new one before testing with your custom version.
Ok, it’s safer. I order some new S06S and LCD3. It will just take some time to receive them.


Do you make some release in order to identify firmware version afterward?
Do you plan to use the LCD3 as a piloting S06S for the FOC motor parameter in real time?

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