HSO Motor Control "Current Scale" Issue

[reesed13]

I am having trouble generating an HSO based project.  I have already confirmed the board works with “Observer+PLL”.  When switching to HSO I am able to select it in the drop down, at which point it:
1. Resets my current sense gain (should be 50), I have no issues replacing this value.
2.  Under Speed Sensing I am provided with an empty Current Scale box, which is a “required field” however upon entering a value it remains red and tells me I cannot enter a value, as “no value is allowed”.

 

Is this a bug or have I configured something incorrectly?  It also seems odd that the current gain setting is cleared, although I can edit that without issue.

 

 

[db16122]

which part number MCU you are using?

[reesed13]

I am using the STM32G431CBT6.

[db16122]

And for the motor driver side, ST EVK or custom board? Not sure your loading status and driver type

[db16122]

Please refer to the setting below, it seems the default value is 29A for current scale

 

[Johnsmiteo]

That does sound like a configuration issue or possibly a bug if the field is simultaneously marked as required and rejects all input. Since the project works correctly with Observer+PLL and the problem only appears after switching to HSO, I'd be interested to know whether others can reproduce it with the same tool version and board configuration. It might also be worth creating a brand-new HSO project to see if the Current Scale field is populated correctly by default. The current sense gain being reset when changing modes also seems unexpected.

[GMA]

Hello ​@reesed13,

It seems that the “Current Scale” parameter is not updated according to the gain or shunt parameters.
Did you try by setting the current sense gain in the json board description files?
If you leave the mouse cursor over the “Current Scale” window, a popup will appear with the expected values.

[reesed13]

​@GMA 

Re-generating it in Motor Control Workbench (6.4.2) does not seem to fix the problem.  When hovering the field, there is no default value provided.  The tip/info popup changes to the second image.  What I type in the box does not seem to have any effect, and it prevents me from generating the project file. 

 

My board JSON file correctly describes the OpAmpGain value as 50, but I included it below if needed.  Additionally a voltage scale of 1V did not really make sense to me, but at least I can change that without any issues.

 

 

[JAMES1968]

I met  the same trouble . due  to setting

[db16122]

Does the best answer solve your problem?

[JAMES1968]

yes,The parameter offsetNetworkAttenuation must not be set to 0 ,but 1.

[XGL]

I have a motor whose phase resistance is 40 mΩ at 20 °C and 45 mΩ at 70 °C. When I set the phase‑resistance parameter to 40 mΩ, the motor operates normally at around 20 °C. However, when the motor temperature rises to approximately 50 °C, frequent start‑up failures occur. How can this problem be resolved?

[JAMES1968]

your motor operates normally ,can you share  your feeling with HSO ?   start torque is enough  from zero speed?

 

[XGL]

HSO supports direct start‑up from zero speed with superior starting load capacity compared to STO. Nevertheless, it is sensitive to phase resistance, and the cutoff frequency of voltage filtering must be properly configured; otherwise, the motor will fail to operate.

[XGL]

Does this mean it is too sensitive to phase resistance?

[JAMES1968]

how about the field_weakening  in HSO ?

 

[JAMES1968]

 HOW ABOUT THE FIELD_WEAKENING  IN HSO ?

[William Romero]

This is a helpful explanation of the issue. The connection between the Current Scale field and the offset network attenuation setting could easily be overlooked when switching configurations. It’s good to know that the value needs to be calculated according to the amplification chain rather than entered directly in that field. The clarification should make it much easier to identify the configuration issue and avoid unnecessary changes to the current sensing settings.