S32K344) Hall signal timing shift

[Tomato1]

Regarding the sample project "MCSPTE1AK344_BLDC_6Step_hall_ll,"

if the installation position of the Hall sensor is misaligned and the rising timing of the signal is slightly off (in case of phase shift),

can this sample software accommodate that? For example, where can I find the settings for electrical angle or offset?

[_Leo_]

Hi,

Thank you so much for your interest in our products and for using our community.

In 6-step based on HALL position sensor demo, HALL signals are processed to calculate the speed and to perform commutation. The last one is performed by the LCU.

What comes to my mind is to delay HALL signals with LUT rise/fall filters. Please refer to 62.6.1.4 Adjustable PWM/FM generator of reference manual.

Hope it helps you. Please let me know if you have more questions about it.

Have a nice day!

[Tomato1]

Thank you for your response. I have a few additional questions. I apologize for the inconvenience, but I would appreciate your answers.

- If the Hall sensor signal is too fast, I don't think it's possible to set a negative value with the LUT rise/fall filters. How should I address this?
- If the rotation speed changes, does that mean I need to adjust the LUT rise/fall filters settings each time?
- Is it possible to effectively address this by changing the advance angle settings? (Are there no advance angle settings in this sample project?)

[_Leo_]

Hi again,

You are correct, LUT rise/fall filters do not accept negative values. Also those values should be changed if speed changes.

In Six-step commutation control there is no advance angle settings. Shaft position obtained by Hall sensor (sensored) or by BEMF voltage zero-crossing detection technique (sensorless).

If your Hall sensor is misaligned, I consider that the sensorless technique is your best option. Or a dual-loop feedback control using both of them.

For more details please refer to S32K3 Motor control SW examples.

Hope it helps you.

[Tomato1]

Thank you for your response.

If I change the microcontroller from S32K344 to another model,

is there a sample project available for six-step commutation control that addresses hall sensor misalignment and phase advance?

[_Leo_]

Sorry for the delay. We currently have a backlog of cases and we try to resolve them as soon as possible.

We do not have any example for six-step commutation control that addresses hall sensor misalignment. You should implement custom code to archive it. Sorry for the inconvenient.

[Tomato1]

Thank you for your response despite your busy schedule. If a sample project that supports the 6-step method for advancing angles is completed, please contact me again in this thread (both with and without the hall sensor). It is very unfortunate, but until then, I will be using microcontrollers from other companies.

[_Leo_]

Of course, I will contact you again if I found a workaround for misalignment of HALL sensors. On the other hand, please double-check with Field Application Engineer assigned to you - either NXP FAE and Distribution FAE. If don’t have such contact yet, please contact our local distributor:

https://www.nxp.com/support/sample-and-buy/distributor-network:DISTRIBUTORS

Have a nice day!