CCS/TMDXIDDK379D: Fail to run motor on IDDK with T-format encoder

Linda Zhang84708

Part Number: TMDXIDDK379D
Other Parts Discussed in Thread: C2000WARE

Tool/software: Code Composer Studio

Hello Champs,

I have connected a PMSM motor with T-format encoder to TMDXIDDK379D (with F28379D controlCARD in H1):

Motor U/V/W to TB1, encoder Data+ to pin6 of H6, encoder Data- to pin 8 of H6, encoder 5V to pin7 of H6, encoder GND to pin1 of H6.

I have import below project "fcl_f2837x_tmdxiddk" in CCSv10.1.0 (CGT version is v20.2.1.LTS):

C:\ti\c2000\C2000Ware_MotorControl_SDK_3_00_01_00\solutions\tmdxiddk379d\f2837x\ccs\sensored_foc

1) According to user guide, In "fcl_f2837x_tmdxiddk_settings.h", BUILDLEVEL is set to FCL_LEVEL2 and POSITION_ENCODER is set to T_FORMAT_ENCODER :

--------------------------------------------------------------------------------------------------------------------------------------------------

#define CGND COLD

#define BUILDLEVEL FCL_LEVEL2

#define SAMPLING_METHOD SINGLE_SAMPLING // DOUBLE_SAMPLING //

#define FCL_CNTLR PI_CNTLR // CMPLX_CNTLR //

#define CURRENT_SENSE LEM_CURRENT_SENSE // SD_CURRENT_SENSE //

#define POSITION_ENCODER T_FORMAT_ENCODER //QEP_POS_ENCODER

--------------------------------------------------------------------------------------------------------------------------------------------------

After the codes are being compiled and loaded into RAM, set "enableFlag" to 1, and then set "runMotor" to Motor_RUN, the motor cannot run and the "runMotor" is always showing "Motor_STOP" status.

If I changed the "POSITION_ENCODER" to "QEP_POS_ENCODER", compiled and then loaded the code again, set "enableFlag" to 1, and then set "runMotor" to Motor_RUN, the motor can successfully run.

My question is: Why did the motor not run with the settings of "T_FORMAT_ENCODER"?

2) If BUILDLEVEL is set to FCL_LEVEL3 and POSITION_ENCODER is set to T_FORMAT_ENCODER :

--------------------------------------------------------------------------------------------------------------------------------------------------

#define CGND COLD

#define BUILDLEVEL FCL_LEVEL3

#define SAMPLING_METHOD SINGLE_SAMPLING // DOUBLE_SAMPLING //

#define FCL_CNTLR PI_CNTLR // CMPLX_CNTLR //

#define CURRENT_SENSE LEM_CURRENT_SENSE // SD_CURRENT_SENSE //

#define POSITION_ENCODER T_FORMAT_ENCODER //QEP_POS_ENCODER

--------------------------------------------------------------------------------------------------------------------------------------------------

After the codes are being compiled and loaded into RAM, set "enableFlag" to 1, and then set "runMotor" to Motor_RUN, the motor cannot run and the "runMotor" is always showing "Motor_STOP" status.

The "tripFlagDMC" has not been set. I have tried swapping two phase of the motor and run the codes again but the issue still existed.

My question is: why was "runMotor" always set to Motor_STOP and why did the motor not run in level3?

Would you please kindly help? Thanks!

Best Regards,

Linda

over 4 years ago

0 Ramesh Ramamoorthy over 4 years ago

TI__Mastermind 27240 points

Surprising, will have to check this.

0 Linda Zhang84708 over 4 years ago in reply to Ramesh Ramamoorthy

TI__Expert 6180 points

Hello Ramesh,

Would you please update whether there is any suggestion to solve this issue or not? Thanks!

Best Regards,

Linda

0 Ramesh Ramamoorthy over 4 years ago in reply to Linda Zhang84708

TI__Mastermind 27240 points

Linda,

Apologies for the delay. I ran the test again and did not see any issue.

If the encoder handshake does not happen, then it will lead to this problem. The T-format encoder may need bit more current and the power supply switch to the encoder may not be turning ON properly. In the BiSS/ENDAT macro of IDDK kit, there is a capacitor C5 whose value need to be changed from 330pF to 10nF.

In the user guide, there is a mention about this. Look at section 5.1.3.1.

0 Linda Zhang84708 over 4 years ago in reply to Ramesh Ramamoorthy

TI__Expert 6180 points

Hello Ramesh,

This issue still exists after changing C5 to 10nF. Would you please kindly suggest? Thanks!

Best Regards,

Linda

0 Ramesh Ramamoorthy over 4 years ago in reply to Linda Zhang84708

TI__Mastermind 27240 points

Simply hard connect the 5V0 to the 5V0-Enc pin on the header H6.

0 Linda Zhang84708 over 4 years ago in reply to Ramesh Ramamoorthy

TI__Expert 6180 points

Hello Ramesh,

5V0 in M12 has been connected with 5V0-Enc pin on the header H6, but the issue still cannot be solved.

Would you please kindly help again? Thanks!'

Best Regards,

Linda

0 Ramesh Ramamoorthy over 4 years ago in reply to Linda Zhang84708

TI__Mastermind 27240 points

Linda,

I think the problem is somewhere else that we have not seen. At this point, it is not IDDK problem. Check with another encoder, or atleast verify the software again. Our code, out of the box, should work fine if the user guide instructions are followed.

rgds,

ramesh

0 Ramesh Ramamoorthy over 4 years ago in reply to Ramesh Ramamoorthy

TI__Mastermind 27240 points

Let us know if the issue is resolved.

0 Linda Zhang84708 over 4 years ago in reply to Ramesh Ramamoorthy

TI__Expert 6180 points

Hello Ramesh,

I have got another PMSM motor with 17-bit T-format encoder and the issue remained the same on it.

Would you please kindly suggest whether it's possible to connect T-format encoder to run motor using IDDK and record a video to show us how to configure at your side or not? Thanks!

Best Regards,
Linda

0 Ramesh Ramamoorthy over 4 years ago in reply to Linda Zhang84708

TI__Mastermind 27240 points

Hmm, I suspect if there is any issue with encoder resolution. Can you compare the bit size of the demo encoder vs the one you are checking. Meanwhile, I will check here as well. Let me know if you find some discrepancies.

0 Linda Zhang84708 over 4 years ago in reply to Ramesh Ramamoorthy

TI__Expert 6180 points

Hello Ramesh,

OK, I will check it. Thank you.

Best Regards,

Linda

0 Ramesh Ramamoorthy over 4 years ago in reply to Linda Zhang84708

TI__Mastermind 27240 points

Any updates?

0 Linda Zhang84708 over 4 years ago in reply to Ramesh Ramamoorthy

TI__Expert 6180 points

Hello Ramesh,

The T-format encoder I used is 17-bit resolution, are there any other parameters about resolution I need to check?

Would you please kindly share the update at your side? Thanks!

Best Regards,

Linda

0 Ramesh Ramamoorthy over 4 years ago in reply to Linda Zhang84708

TI__Mastermind 27240 points

I am looping in the relevant experts.

0 Lori Heustess over 4 years ago in reply to Ramesh Ramamoorthy

TI__Guru* 91125 points

Linda,

Can you check if the C28x is sending a packet to the encoder? Check the interface signals - the C28x will send them once, and then wait for a response. So you will need to setup a trigger to catch the waveform. I believe there is a probe point on the IDDK to check these signals.

Check TxEN - this will correspond to data going out on DATA_OUT
Check DATA_OUT
- Make sure the duration of a single bit is 2.5 MHz. If it is not 2.5 MHz then the encoder will not respond.
- If F2837x is running at 200MHz then this should be correct. Note that the F2837x LaunchPad and ControlCard have different input clocks so check the project's build options -> C2000_compiler -> Predefined Symbols. The symbol _LAUNCHXL_F28379D should NOT in the project's predefines when using a controlCard.

Check that the encoder is powered properly and not current limited. It is better to provide the power externally as some t-format encoders draw a rush current on power-on which is not supported by the board.

Regards

Lori

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CCS/TMDXIDDK379D: Fail to run motor on IDDK with T-format encoder