DRV10987: DRV10987

Ramesh Babu

Prodigy 10 points

Part Number: DRV10987

Dear Sir/Madam,

We are getting an issue while we are driving the motor to rotate fan.

when motor/fan is rotating at low speed/starting

1)the fan is rotating back/jerk for a small time and coming forward and works normally.

2)fan is rotating forward and stoping then it is working properly.

Please find the attached video for reference.

Best Regards

K Ramesh Babu

over 3 years ago

0 Matt Hein over 3 years ago

TI__Mastermind 21805 points

Hello Ramesh, and thanks for your question!

Can you provide the register settings that you are using for the DRV10987?

Normally we see that using IPD as a startup method (rather than align) helps prevent movement before motor startup.

Thanks,

Matt

0 Ramesh Babu over 3 years ago in reply to Matt Hein

Prodigy 10 points

Hi Matt Hein, and Thanks for reply!

Please find the attached csv file.

Best Regards

K Ramesh Babu

Stealth Closed loop 41hZ.csv

0 Vishnu Balaraj over 3 years ago in reply to Ramesh Babu

TI__Mastermind 24405 points

Hi Ramesh,

Thanks for sharing the configuration. I checked the config file and found the IPD current threshold set too high (3.2A). This could potentially cause the initial movement that we are seeing during startup. What is the rated current of the motor? Can you try decreasing the IPD current threshold and try again? If this doesn't help, can you try decreasing the IPD clock frequency to 47 Hz or even below?

I would highly recommend you to check the IPD tuning guide to optimize IPD tuning.

Regards,

Vishnu

0 Ramesh Babu over 3 years ago in reply to Vishnu Balaraj

Prodigy 10 points

Hi Vishnu, and Thanks for the reply, The rated current of the motor is 2A but we are driving a max current of 1.5A. Even after setting the IPD current threshold to 2A and IPD clock frequency even below 47Hz still, the issue is the same.

Best Regards

K Ramesh Babu

0 Vishnu Balaraj over 3 years ago in reply to Ramesh Babu

TI__Mastermind 24405 points

Hi Ramesh,

Can you set the IPD current threshold to 0.6A , 0.8A or 1.0 A and try again to see if the backward spin goes away? Keep decreasing IPD current threshold till the backward spin goes away

Also, do you see a delay (around 2-3 seconds) in motor startup after issuing the speed command? If so, then can you disable ISD and try again to see if this delay goes away?

Regards,

Vishnu

0 Ramesh Babu over 3 years ago in reply to Vishnu Balaraj

Prodigy 10 points

Hi Vishnu, Thanks for reply!

We have set the IPD current threshold to 0.6A, 0.8A or 1.0A, and We disable the ISD but still the issue is same.

please find the Phase to phase resistance 2E and Kt Back EMF is 471 of the motor.

can we have some initial discussion in teams, so that you could suggest some solution.

Best Regards

K Ramesh Babu

0 Vishnu Balaraj over 3 years ago in reply to Ramesh Babu

TI__Mastermind 24405 points

Hi Ramesh,

I'm okay to have a discussion in teams. Please go ahead and send the meeting invite. My email: v-balaraj@ti.com. I'm available tomorrow (19 March) at 6:30 PM IST. Can you have the test setup ready during the call?

Regards,

Vishnu.