• State Resolved
  • Locked Locked
  • Replies 7 replies
  • Answers 1 answer
  • Subscribers 29 subscribers
  • Views 247 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:

DRV10983Q1EVM: Analog and PWM speed control not working

DRV10983Q1EVM: How to control the motor speed

suy
Intellectual 995 points
Part Number: DRV10983Q1EVM

Hi team，

  According to the specification, the motor speed can be controlled by PWM in three ways. However, after the motor is controlled by GUI software, I made the following Settings, none of which can control the motor speed:
1. Set the value of speed in speed control. The motor speed is always 25Hz, but the speed command changes with the set value
2, J2 jumper to 1-2, use analog input speed pin, change analog input voltage through potentiometer, motor speed does not change
3, J2 jumper to 2-3, use PWM input with speed pins, through the signal generator output PWM signal, real-time change duty ratio motor speed does not change.
How to use these three ways to control the motor speed? Here are the GUI software Settings.

In addition, during the operation of the motor, after shaking the motor to stop its rotation, the motor cannot rotate itself again. May I ask whether the parameters can be adjusted to make the motor work again automatically after vibration stop?

  • 0
    TI__Mastermind 24405 points

    Hi Suy,

    Thanks for posting your question in MD forum. In the GUI screenshot, I see that the closed loop is disabled. This means the motor will always spin in the open loop and will never enter closed loop. In open loop, motor will ramp to the configured open to closed loop threshold (25.6 Hz). Speed is not controlled in open loop and the device will not respond to any speed command. Please enable closed loop by un-checking the "Closed loop disable" bit. If you see any faults getting triggered, please refer to the DRV10983Q1 tuning guide. If you see "Abnormal BEMF fault" or "Closed loop stuck" fault, refer to the "DRV10x Tuning lead angle" app note.  

    Motor might stop when device triggers a fault. Unfortunately, user has to manually clear the fault to restart the motor.

    Regards,

    Vishnu

  • 0 in reply to Vishnu Balaraj
    Intellectual 995 points

    Hi Vishnu，

        I set the motor work in closed loop，the motor stops working after 5s with howlround. then 3s the previous action is repeated. At this time, the interface prompt is displayed close loop stuck，i find the lead time must be calculate the ratio of phase current over motor speed，could you tell me how can i get the phase current？

         Another，the following are the various parameters of the motor. Can you give some reference for the various parameter Settings of the GUI interface?

         Voltage ：12V

         Pole      ：12

         Max speed ：2878 rpm

         Max current ：1.5A

         Wire Res ：4.33ohm

         Wire Inc   ： 0.55mH

         

         

       

  • +1 in reply to suy
    TI__Mastermind 24405 points

    Suy,

    Firstly, keep tuning the lead angle until the estimated BEMF constant read back from MotorKt (address: 0x03) gets closer to the programmed BEMF constant (40.48 mV/Hz). After this step, measure the motor current using a current probe and oscilloscope to optimize the efficiency.

    Regards,

    Vishnu 

  • 0 in reply to Vishnu Balaraj
    Intellectual 995 points

    Hi Vishnu，

        No matter how I adjust the lead time（from 80us to 4.8ms）,the estimated BEMF constant read back from MotorKt is always about 3500mV/Hz，this value is much different from the programmed BEMF constant(40.48 mV/Hz). Is there any problem with other settings？

  • 0 in reply to suy
    TI__Mastermind 24405 points

    Suy,

    Can you increase the open to closed loop threshold and try again? 

  • 0 in reply to Vishnu Balaraj
    Intellectual 995 points

    Hi Vishnu，

       I‘m so sorry，i worte the phase to center tap resistance as the phase resistance ，it should be half the latter。

       Now the motor can adjust the speed in closed loop mode.

       Thanks a lot!

  • 0 in reply to suy
    TI__Mastermind 24405 points

    Suy,

    Thanks for letting us know.

    If your issue has been resolved, please help us out by clicking the green “This Resolved My Issue” button. If you have a related question, please use the orange "Ask a related question" in the top right corner of the page.

    Regards,

    Vishnu