• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 309 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Original question:

DRV8353: DRV8353

DRV8353RS-EVM: LAUNCHPAD-F280025C :- over current fault and current unbalance

Gaurav rajput
Prodigy 80 points
Part Number: DRV8353RS-EVM

Dear sir, 

I have  DRV8353RS-EVM , LAUNCHPAD-F280025C and Hub motor .

(Note:-  I am using 24 to 30 volt power supply and my hub motor max voltage are 48 volts and 102 hz frequency)

Recently I have complete the DMC_Level_1 as per user guide but as I move forward to DMC-2 I am facing the following issues and question.

1) At low speedRef_hz = 10, motor spin fine with no fault (Default max_current = 6 amp and over_current = 7.5).

2) As I increase the   speedRef_hz = 25 , I got overcurrent fault issue. (as we know default overcurrent in firmware is 7.5 amp, when I set that to high around 12 amp, then I able to run the motor again).

3) I found the same issue on this forum, I get one solution to set the overcurrent limit by increasing  and decreasing the dacVIH and dacCVIL inside the firmware. is it fine to do that in my case ?

4) what is the cause of current unbalance fault?

Regards,

Gaurav

  • 0
    TI__Genius 12231 points

    Hi Gaurav, 

    Thank you for your question and using our forum! 

    Allow me some time this week to look over this info and determine appropriate next steps. 

    Best Regards,

    -Joshua

  • 0 in reply to Joshua Maize
    TI__Genius 12231 points

    Hi Gaurav,

    Thank you for your patience.

    After overview of your issue I believe it may be best to involve our C2000 team to better help answer your inquiry. 

    Please expect a further response this week.

    Best Regards,

    -Joshua

  • 0 in reply to Joshua Maize
    Prodigy 80 points

    Hello sir ,

    I am try to tune the speed loop , but I am facing a problem.

    as I achieved the desired result by tuning the PI speed loop, but when I just power-up the board after switch-off and after setting the desired PI value of speed loop . we get the peak overshoot evetime when power reset, after that works fine, below I attached image of the same please let me know the possible solution.

    Thanks & regards,

    Gaurav

  • 0 in reply to Gaurav rajput
    TI__Genius 9261 points

    Hello Gaurav,

    I'll address each of your questions in order.

    1. The motor over-current limit is going to depend on the specs of the motor you're using.
      1. In user_mtr1.h
        1. USER_MOTOR1_OVER_CURRENT_A
        2. USER_MOTOR1_MAX_CURRENT_A
      2. Adjustments to these values will, in turn, adjust the DAC compare values you mentioned- don't adjust those directly.
    2. Current unbalance fault is intended to indicate that the magnitude of the current between phases is significantly different. If you're seeing this fault, the physical parameters of your motor may not be correctly implemented in user_mtr1.h
    3. To avoid overshoot, there's supposed to be a startup ramp. Is your system ever entering the startup state?

    Regards,
    Jason Osborn