TMS320F28335: Negative current at input current @ BLDC Motor Driver

Part Number: TMS320F28335

Hello,

I am developing BLDC driver and Input voltage is 48VDC.

I have question about a negative current at input side.

Could you let me know the reason why there is a negative input current periodically during short time.

If the hall sensor is deviated , it is possible to have negative current during short time?

Do you think it has the effect on efficiency?

Please le me know the reason.

B.regards

0 Ramesh Ramamoorthy over 5 years ago

If the motor is not regenerating, I dont understand why. You will have to review the commutation states to understand that.

0 SY over 5 years ago in reply to Ramesh Ramamoorthy

Hi Ramesh Ramamoorthy,

Thank for your comment.

I think this is a short negative current that occurs once every time the position of the hall sensor changes near the transition of the commutation.

I am doubting the deviation of hall sensor location for measuring the commutation.

Do you have any comment?

B. regards

0 Ramesh Ramamoorthy over 5 years ago in reply to SY

No...

0 SY over 5 years ago in reply to Ramesh Ramamoorthy

Hi Ramesh Ramamoorthy,

I think you think drive didn't do well.

BLDC drive did the speed control well and I am focusing on the efficiency of BLDC drive.

I would like to know the effect of negative current at the efficiency.

B. regards

0 Ramesh Ramamoorthy over 5 years ago in reply to SY

Sorry, we dont have an answer to this query as we cant actually experiment the same way.
You may have to research the answer else where.

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