DRV8350H-EVM: DRV8350-EVM

Hey Najma,

Thank you for your question. I will look into this EVM and aim to provide feedback by early next week.

Best,
Akshay

Hey Najma,

Have you done this step?

Also I suggest modifying the Stall detect parameters in the SW to prevent accidentally triggering the stall detection.

Was the motor spinning at all before the fault got triggered?

The SLVC755 should be the correct SW. and ti seems to be the one used in the E2E post you linked as well.

Best,
Akshay

Hi Akshay , 

I had fixed those errors and build the code before testing. The motor wasn't spinning at all before the fault got triggered. I'll try modifying the stall parameters. 

thanks for the response,

Najma 

Hey Najma,

Thanks for the update.

Best,
Akshay

Hello Akshay,

In 6*PWM sensored motor , the motor is running only in reverse direction. It is triggering overcurrent fault when I tried to spin in forward direction. 

Here are the steps I followed

target programmed with 6pwm firmware

GUI connected - DRV8350H-Sensored - 6PWM 

Driver enabled

Motor Phase current limit 5A

Direction forward

Motor enabled

As I increased the motor speed to 22% , it triggered overcurrent fault 

I tried the Reset button and it didn't help me get out of Fault state. Had to reprogram the target to spin the motor again in reverse direction. 

thanks

Najma 

Hey Najma,

I thought you had successfully evaluated 6x mode and moved on to 1x mode. Did you see this issue initially on the 6x mode?

Were you able to measure the phase current to confirm if an overcurrent event has occurred?

Best,
Akshay

Hi Akshay ,

We were able to get it working in 6*PWM and run some basic tests last week. Not sure why it is triggering overcurrent fault now. Is there any documentation/guide  available to debug the common issues in DRV8353 ?

thanks

Najma 

Hello Akshay,

Can we test a 40 pole motor using the DRV8350 GUI . It seems the GUI drop down menu only supports a max of 16 poles. Is there any workaround ?

thanks

Najma 

Hey Najma,

Can you ensure that the hall connections are wired correctly?

Phase current could be helpful in detecting the difference between forward and reverse direction in this case. Did you test switching directions in the initial 6 PWM test?

Are you doing these tests on the modified DRV8350 board you used to test 1x mode?

We have these guides which might contain some useful debugging advice.

https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/1176539/faq-quick-guide-to-debugging-common-issues-in-bldc-motor-drivers

https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/1160331/faq-debugging-faults-with-hardware-variant-devices

The DRV8350 DS would also be a good resource to learn about the overcurrent fault.

The GUI is optimized for max of 16 poles so firmware edits might be required to work with 40 pole motor.

Best,
Akshay

Hi Akshay,

The Hall sensor wires are connected in the correct order and  had verified it using the method mentioned in this link https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/845535/faq-how-to-ensure-correct-alignment-of-hall-sensors-and-your-motor

I had modified the board to test 1*PWM  , but removed the hall sensor 0hm resistors for testing 6 PWM sensored.

For the initial 6 PWM sensored testing 

connected the hall sensor inputs to J2,and selected 5V for hall sensor power (J1)

• changed PWM_Mode variable in the Init.c file to  0b0 , build & programmed the target
• The GUI  connected to the  "sensored motor" option. 6*PWM mode was selected

I was able to run the motor in both forward and reverse directions .

Also could you tell me what kind of firmware changes is required to evaluate a 40 pole motor ? Is it just a variable change ? 

thanks

Najma 

Hey Najma,

I am wondering if some hardware damage happened with the soldering process. If not then a complete power down and power up of the board should have cleared any software related issues. Do you happen to have an extra EVM so that the 1x and 6x can be tested separately?

Phase voltage and current waveforms could be used to start debugging the reverse vs forward issue.

I will need to look a bit more into the actual SW for the higher pole possibility. 

Best,
Akshay

Hi Akhsay ,

Please let me know if you have any  updates on the firmware changes  required to evaluate a 40 pole motor ? 

thanks

Najma 

Hey Najma,

I was wondering if it would be possible to increase the RPM to make the SW simulate driving for a 40 pole motor. For ex. select 10 pole in GUI and multiply the RPM by 4 to potentially have it work for 40 pole motor.

Best,

Akshay

Hi Akshay,

I don't think the DRV8350 GUI allows to multiply the RPM . Please correct me if I'm wrong.
I have changed the percentage of duty cycle value using the Set Motor Speed slider to set an appropriate speed during the initial testing and noticed that  the GUI reports back the RPM.

thanks

Najma

Hey Najma,

Marking the thread as closed for now. If your question was addressed please mark the thread as resolved.

Please let us know if you have more questions or if you have new questions please post them as a new thread.

Best,
Akshay