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Hoverboard Motor, Noisy after FW update, Anti Cogging, PID values for low rpm

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JulianT
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Joined: 2020-01-14 16:25
Posts: 10
Hoverboard Motor, Noisy after FW update, Anti Cogging, PID values for low rpm

Hi all.

My setting: 4 WD with Hoverboard-Motors (about 350W) and VESC 4.12

Steering like a Tank

Encoder: Hall Sensors

The 4 esc are controlled via UART by a micro controller.

 

After the Firmware update my Motor get very noisy. Comparing the default setting from the older FW Version the Current Kp and Ki settings (FOC - > General Tab) have been increased. Setting them to the old Values solved the Problem.

Current KP: 0,15

Current KP: 134.0

Observer Gain 2.0

 

Beside this i had great Problems for smooth running below 500 erpm. I solved this by switching to open loop mode for speed < 500erpm with a custom made Firmware (by a friend) because a UART openloop command is still not implemented. But because my programming skills are low and I wanted to update the Firmware and get rid of the open loop mode (great waste of energy) I played again with the PID settings.

 

The Main Problem finding some good settings for the PID controller is that i need very high currents if i want to turn the vehicle with low speed. I also tried the Odrive 3.5 with is running very smooth at low RPM but because of the suggested small PI value it takes 20 seconds to reach max current at low speed.

So for everybody with the same Problem i suggest these settings:

Current KP: 0,22

Current KP: 1.0 (Yes it is really 1% of the default setting)

Observer Gain 2.0

 

Speed-PID values

 

Speed PID Kp 0,00810

Speed PID Ki 0,09000 (I need alot for high current at low erpm)

Speed PID Kd 0,00010 (seems to make no difference to choose 0 or 0.00099)

Speed PID Kd Filter 0,0

Minimum ERPM 0,0

Allow breaking: True

RAMP eRPMs per Second: 1500 (4000 erpm is the max i could reach with

20V)

Speed Tracker: Observer

The Problem with these settings: if you drive current mode it takes long time to reach high speed.

With this settings i could get more or less smooth running down to 100 erpm.

If someone has also experience please share.

One of the problem might be that the Hall-Sensors have a bad resolution (80 / 360degree) so speed estimation might be a problem.

Does anybody know where I could change some filter settings to get a smother calculated speed?

Is it planned to implement the anti cogging algorithm in the Firmware?

 

NolanCash
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Last seen: 11 months 5 days ago
Joined: 2022-01-08 01:46
Posts: 1

hello! so im about to get some VESCs to drive hoverboard motors for an art project and i was wondering if you had any details that might help me along this new and interesting possess