• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 82 subscribers
  • Views 363 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.

CCS/TMS320F28069M: Question about lab projects of InstaSPIN-FOC

yong kuang
Prodigy 70 points
Part Number: TMS320F28069M
Other Parts Discussed in Thread: BOOSTXL-DRV8305EVM,

Tool/software: Code Composer Studio

Dear All,

I am using the Lab02a, Lab02b and Lab02C of InstaSPIN-FOC on my LaunchPadXL TMS320F28069M and BOOSTXL-DRV8305EVM to identify the motor paramters, but I found the MOTOR_Ls calculated for the Lab02C are different with lab02a and lab02b, the value calculated from Lab02c is about 1.299*e-5 H, while in Lab02a and Lab02b are 5.279*e-5 H.

What may cause the difference?

Thank you.

  • 0
    TI__Guru** 115440 points

    That's right. As you see in the lab guide, you have to use the lab02c for the motor since it's a low inductance motor. Lab02a and lab02b can't support such low inductance motor identification.

  • 0 in reply to Yanming Luo
    Prodigy 70 points

    Thank you.

    You means the result tested from Lab02c will be more precise?

    Also, I have met a problem. I use the motor parameters tested in Lab02C to run the Lab03a, but it always have "USER_ErrorCode_ctrlFreq_Hz_Low" error.

    The related parameters are listed in the following:

    USER_MOTOR_Rs: 1.155

    USER_MOTOR_Ls_q: 5.508e-5

    USER_PWM_FREQ_kHz: 80kHz

    USER_NUM_PWM_TICKS_PER_ISR_TICK: 1

    USER_NUM_ISR_TICKS_PER_CTRL_TICK: 1

    So the USER_CTRL_FREQ_Hz is 80kHz.

    Is there any document to introduce how to set the Frequency?

    Thank you again.

  • 0 in reply to yong kuang
    TI__Guru** 115440 points

    1. Right, lab02 is good for low inductance motor.

    2. You can set the PWM frequency to 80KHz. but you should set the USER_NUM_PWM_TICKS_PER_ISR_TICK to 3. It's difficult to support the USER_ISR_FREQ_Hz or  USER_CTRL_FREQ_Hz to more than 25kHz in instaSPIN-FOC limit to the CPU bandwidth. Please check USER_IQ_FULL_SCALE_FREQ_Hz if you set a very higher value for it, if yes, the USER_IQ_FULL_SCALE_FREQ_Hz must be less than USER_CTRL_FREQ_Hz.