• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 84 subscribers
  • Views 823 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

TMS320F28027F: Motor Torque

Rajan Joshi
Expert 1020 points
Part Number: TMS320F28027F
Other Parts Discussed in Thread: DRV8305

Hello, 

I am using a PMSM motor with the DRV8305. 

Once the motor is identified I try to run lab 5b and when I do so, I am not able to get a smooth run from the motor. 

Once in a while it will start turning smoothly, and as soon as I apply any load it will start to stall and overheat. 

The motor reaches a very high temperature and I have to turn it off. I dont understand the issue with this motor.

What should i do to fix this problem ?

Regards,

Rajan Joshi 

  • 0
    TI__Genius 17370 points
    Hello,
    I am writing to let you know that a C2000 team member has been assigned to this post and should be answering shortly.

    Regards
    Baskaran
  • 0 in reply to Baskaran Chidambaram
    Expert 1020 points

    Thank you Baskaran. 

    I have tried some additional tests. 

    I replaced the resistors for the voltage sense to 17.8k from 62k to get better feedback for my 12 V system, no luck. 

    I can see run the motor perfectly normal using lab 4 with current control. The problem seems to be caused when I close the speed loop. 

    Later I tried to change the DRV 8305 to 8301 to run the motor. I am able to identify it but the inductance is very low. (e-12). Can I change voltage resistors on this board as well for better feedback? I am not sure which resistors need to be changed other then R37,R39 and R41.

    I am currently in the process of trying to run the motor with the 28069 with 8301 and 8305 to see if it will able to identify and run the motor with torque.

    I am using this motor to produce high torque at lower speeds.

    Please advise on how I should move forward with this. 

    Regards,

    Rajan Joshi

  • 0 in reply to Rajan Joshi
    TI__Guru** 116120 points
    Make sure that using lab02b or lab02c (for low inductance motor) to identify the motor parameters first and set these parameters in lab05b.
    Check the Kp and Ki of speed PI regulator, and adjust both parameters to make sure the motor run smoothly without load first, and then tune these two parameters to run motor well. Maybe you have to tune the parameters of current regulator also if the performance is not good enough.
    For startup and low speed with high load, you'd better to do Rs calibration first to get a precise Rs which can improve the startup performance.