KLS-S controller issue : rev limited ?

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Fardenco   10 µW

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KLS-S controller issue : rev limited ?

Post by Fardenco » Dec 07 2019 3:05pm

Hi guys, I'm currently on the project of building my first electric vehicle, but I have a problem with the controller (I guess).
Everything works great at low speed, but at around 1800 to 2000rpm, the motor speed drops down quite brutally, then goes up, drops down again, etc., like you would see on a gas engine with the rev limiter.
Please have a look at this video : https://mega.nz/#!9FZgkSBQ!2We1l1p6rBtG ... ypjRHWuvnY
I've checked the max speed settings, it's supposed to be 6000rpm, and with the motor I have, the controller could even be able to reach 12.000rpm.
It doesn't look like a software limit to me, because I tried to put the limit at 1000rpm to see what happens, and I found that the motor revs up quickly (because there's no load) but comes down gently to 1000, everything is smooth, not like in the video.
Here you can find screenshots of the settings :
https://mega.nz/#!pBIGQKYb!ghLHdVJaVcSg ... WYTKktqOA0
https://mega.nz/#!kRQSxIZT!e6iUN082oiMj ... UkygMOgnSs
The controller is a KLS6025S, and I don't know the ref of the motor but I know it's a 6 pole pairs BLDC motor.
Do you have any idea of what could cause that ?

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eee291   100 kW

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Re: KLS-S controller issue : rev limited ?

Post by eee291 » Dec 07 2019 3:46pm

What kind of motor do you have?
I think you might be hitting the E-rpm limit.

Fardenco   10 µW

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Re: KLS-S controller issue : rev limited ?

Post by Fardenco » Dec 07 2019 4:03pm

It's a sensored brushless motor, 6 pole pairs, inrunner. I don't know much more because I don't know its reference.
The erpm limit of the controller should be 70.000rpm, that's what the manual tells us.
The motor has 6 pole pairs, so at 2000rpm that's 12.000erpm, right ? Much bellow the maximum of the controller so I don't think that's the problem, but maybe I'm wrong

Voltron   10 MW

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Re: KLS-S controller issue : rev limited ?

Post by Voltron » Dec 08 2019 5:52am

Losing sync with the Hall sensors? Maybe they're not sending a strong enough pulse to the controller as the rpms build?

Fardenco   10 µW

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Re: KLS-S controller issue : rev limited ?

Post by Fardenco » Dec 08 2019 6:12am

That's interesting, do you know if there is a way to test this ?

larsb   100 kW

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Re: KLS-S controller issue : rev limited ?

Post by larsb » Jan 01 2020 11:55am

There are more setting screens, please show all, especially the ones with speed limits and the basic settings.
Did you perform auto-identify succesfully?
Do you drive the halls with 12V or 5V?

The sound from the motor was strange, what is it? hub motor, mid drive or something not ebike related?
- Please upload a picture of the motor and all markings.

Does motor and controller work the same way as in video when loaded? sometimes the kelly program can loose sync unloaded.

-What kind of throttle do you have? Is it a hall sensor throttle?

-What throttle limits have you set?
Ride on!

Fardenco   10 µW

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Re: KLS-S controller issue : rev limited ?

Post by Fardenco » Jan 14 2020 12:16pm

Hi,
I'm sorry, I did not see your message.
Here are the screenshots :
Vehicle : https://mega.nz/#!JRhgEKrQ!TdqAN1UNQCbU ... 3wSWEZFnNs
Motor : https://mega.nz/#!pBIGQKYb!ghLHdVJaVcSg ... WYTKktqOA0
Control : https://mega.nz/#!kRQSxIZT!e6iUN082oiMj ... UkygMOgnSs
The hall sensors are powered by 5V from factory, but I tried to power them with 12V, nothing changed.
Here is a picture of the motor : https://mega.nz/#!EIRU0KCR!DAkSdYZBeYNe ... XFzq-C2nos
Here is the motor opened : https://mega.nz/#!FRJw0S4b!JIq8fBK9l-Sz ... O6K0G26YA0
Unfortunately, I could not find any marking anywhere on the motor.

I will try with the wheel and chain attached. Do you think that would be a sufficient load ?
The throttle is a potentiometer inside a handle, like this one : https://www.amazon.com/dp/B07VJWX9ZD

I tried various settings for the throttle limit, but I think that's the problem because on the monitoring screen, the one you see on the video, the "TPS Pedal" value stays stable at around 200 when the problem happens, but I might be wrong

Anyway thank you for your time !

larsb   100 kW

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Re: KLS-S controller issue : rev limited ?

Post by larsb » Jan 14 2020 1:39pm

Think i’ve seen this issue before on ES. From memory that time the recommendation was to use kelly kbs controller since motor back emf is square shaped.
Motor might be poor match for sine controller.

What is your battery voltage and what is motor kV?
Do you get any errors at all in program?
Have you changed PID parameters from default?
Ride on!

larsb   100 kW

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Re: KLS-S controller issue : rev limited ?

Post by larsb » Jan 14 2020 1:39pm

Think i’ve seen this issue before on ES. From memory that time the recommendation was to use kelly kbs controller since motor back emf is square shaped.
Motor might be poor match for sine controller.

What is your battery voltage and what is motor kV?
Do you get any errors at all in program?
Have you changed PID parameters from default?
Ride on!

Fardenco   10 µW

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Re: KLS-S controller issue : rev limited ?

Post by Fardenco » Jan 14 2020 3:30pm

The battery voltage is 48V (13S Li-ion), I don't really know the motor's kv. I could measure it. My plan was to see how it runs, and adjust the chain sprocket size according to the results.

I don't get any error when I change settings on the controller.

I tried the default PID values, and I also tried to tinker with them, still no luck.

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eee291   100 kW

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Re: KLS-S controller issue : rev limited ?

Post by eee291 » Jan 14 2020 4:09pm

Could you post a pic of the Motor?
Also, what is the RPM value in the monitor section at WOT?

Fardenco   10 µW

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Re: KLS-S controller issue : rev limited ?

Post by Fardenco » Jan 14 2020 4:18pm

Image

The displayed speed is quite erratic, you can see it on this video : https://mega.nz/#!9FZgkSBQ!2We1l1p6rBtG ... ypjRHWuvnY

larsb   100 kW

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Re: KLS-S controller issue : rev limited ?

Post by larsb » Jan 15 2020 1:35am

The speed in kelly readout is always a bit erratic.

I could not find the post i was looking for, only this:
viewtopic.php?t=98568#p1458573

Don’t think you’d be able to know the kV without a scope since there is doubt that controller limits rpm. Try it with real load (driving).
wheel and chain will not be enough load.
Ride on!

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eee291   100 kW

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Re: KLS-S controller issue : rev limited ?

Post by eee291 » Jan 15 2020 5:38am

It's one of those Big Block motors and they work terribly with Kelly sine wave controllers.
I had to go with a sensorless trapezoidal controller from Greentime to get it to spin properly.

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