cancel
Showing results for 
Search instead for 
Did you mean: 

Can we use Hall Sensor as main sensor and no auxiliary sensor to run the motor? Can we control the speed of the motor? how to decide the placement electrical angle? Default 300 in Workbench.

VGani.1
Associate III

Hi, I am using Motor Control workbench to run the motor using Nucleo-F446RE and X-NUCLEO-IHM08M1. Initially I used Main Sensor "Observer+PLL" and auxiliary sensor "Hall Sensor" and I can able to control the motor. Now our requirement is to use only hall sensor as Main sensor. In this case the motor is able to run but at a fixed speed and not varying to any change in parameters.

Thank you.

Regards

Vijay Ganisetti.

18 REPLIES 18
cedric H
ST Employee

Hello Vijay,

To answer your question, yes you can use Hall sensor as main sensor and no auxiliary sensor.

The fixed speed issue is due to a bad hardware connection of your hall sensor pins, so this is the first thing to fix.

Once it is done, you need to properly configure the placement electrical angle.

With the MCSDK 5.Y.2, and your project with the Hall sensors as auxiliary sensor, you can view the electrical angle coming from both algos STO-PLL, and HAll sensors. (even if only the STO-PLL is actually used to control the motor)

The both sawtooth must be superimposed. The shift between them is controlled by the placement electrical angle parameter.

Regards

Cedric

Hi Cedric,

Do you mean to measure electrical angle from the (observer+PLL ) and compare with Hall Signal (Ha) to see both are aligned together? If not check the displacement angle??

0693W00000FB9DpQAL.png

cedric H
ST Employee

The idea is to print the Observed elec angle coming from the STO-PLL algo, and the measured electrical angle coming from the Hall sensor auxiliary. You should see the 2 sawtooth . The hall signals plot is not helpful for Hall sensor tuning.

Do you use the 5.4.X or 5.Y.2 SDK ?

Cedric

VGani.1
Associate III

Hi Cedric,

I use 5.4.7 version. Yellow curve is the observed elec. angle and green is the measured electrical angle, However it is difficult to observe the elec angle measured by Hall sensor.

0693W00000FB9MNQA1.png

cedric H
ST Employee

0693W00000FBAwmQAH.pngThis is the curve you should observe.

On 5.4.7 it can be observed with the DAC only.

From your picture, the first thing is that your both curves are opposite, This means that your Hall sensors connexion are not Ok.

The second point is that your observed angle go back to 0, could you print your three hall sensors signal ? I wonder if the three sensors toggle correctly.

Regards

Cedric

VGani.1
Associate III

Hi Cedric,

Since from the previous result, both measured and observed elec. angle are opposite. I changed Hall signal 2 and 3, now the measured and observed elec. angle are in right direction. I measured in both positive and negative direction to see the difference.

in DAC channels, i think Channel 2 is damaged. The signal is not ideal.

0693W00000FBIzsQAH.png

cedric H
ST Employee

Hello Vijay,

With the release 5.Y.2, we have access to high frequency signals through the UART and the new motor Pilot tool.

It would we worth to plot both angle with this release and the motor Pilot.

If it is not possible, could you zoom in the observed angle to see at which frequency it toggles to 0.

To be honest I have never seen such kind of shape before.

Regards

Cedric

Hi Cedric,

I used 5.Y.2 but still the signal is same. I hope the pin (PA5) in CN10 might get damaged.

0693W00000FBSCMQA5.png0693W00000FBSC2QAP.jpg

cedric H
ST Employee

Hello @Community member​ 

Sorry, I was not clear enough. The purpose of switching to 5.Y.2 and the new Pilot is to be able to see these angles inside the mPilot, and not with the DAC output and the scope.

If you look at the top right of your mPilot screen shot, you have two buttons in the box "Graph and Record". If you click on the graph button, it will open a new window. If you right click inside this window, you will be able to select the signals you want to plot. (HALL_EL_ANGLE & STOPLL_EL_ANGLE)

With the new communication protocol we increased the communication speed so much that we are able now to dump FOC variables at PWM frequency.

It will at least remove your concern about the DAC output pin.

Before doing this, could you zoom in your oscilloscope to see at which frequency the HALL angle switch to 0.

Regards

Cedric