TMS320F280049C: Assistance Needed for Motor Speed Instability on Custom Board Using TMS320F280049C & DRV8320RS

Hyu,

If you've already verified the power supply is stable, then I'd first suggest comparing the signal integrity of the current and voltage signals (particularly the current signals) on the custom board vs the LaunchPad + Booster Pack HW. If the signal integrity is lower and/or there's generally more noise in the system, then control loop may not be able to sustain the same output maximum.

Additionally, it may not be a bad idea to verify that your 3 changed parameters do not cause any problems with the FAST estimator. If using the current gen motor control SW development kit (the C2000Ware Motor Control SDK), then refer to {MCSDK}/solutions/{Solution folder}/docs, and there should be a 'parameters calculation' document in most solutions. If using the previous gen motor control SW development kit (MotorWare), then refer to the {motorware}/docs/labs/motorware_selecting_user_variables.xlsx.

Regards,
Jason Osborn

Hi Jason,

In addition to the changes mentioned regarding my custom board (primarily updates to parameters in the user.h file), I also modified the pin configurations for PWM, ISEN, and VSEN in the hal.c file to align with the hardware design.

Initially, I faced some challenges due to inconsistencies between the software and hardware, as the hardware was designed by someone else. As a result, I was unable to successfully run Lab05. After making a few adjustments, I was eventually able to run Lab05 and obtain the motor parameters, which were quite similar to those obtained using your development kit.

However, despite these efforts, I could not achieve the same level of performance as your kit. I am uncertain whether the changes in the hal.c file are contributing to the issues I am experiencing.

Thank you for your time and support.

Some changes I made following the code below:
#if (BOOST_to_LPD == BOOSTX_to_J1_J2)
// initialize PWM handles for Motor 1
obj->pwmHandle[0] = EPWM1_BASE; //!< the PWM handle, GPIO8/GPIO9
obj->pwmHandle[1] = EPWM3_BASE; //!< the PWM handle, GPIO4/GPIO5
obj->pwmHandle[2] = EPWM5_BASE; //!< the PWM handle, GPIO0/GPIO1

// initialize PGA handle
obj->pgaHandle[0] = PGA1_BASE; //!< the PGA handle
obj->pgaHandle[1] = PGA3_BASE; //!< the PGA handle
obj->pgaHandle[2] = PGA2_BASE; //!< the PGA handle

// initialize CMPSS handle
obj->cmpssHandle[0] = CMPSS1_BASE; //!< the CMPSS handle
obj->cmpssHandle[1] = CMPSS3_BASE; //!< the CMPSS handle
obj->cmpssHandle[2] = CMPSS2_BASE; //!< the CMPSS handle
#endif

#if (BOOST_to_LPD == BOOSTX_to_J1_J2)
// configure the interrupt sources
// configure the ample window to 15 system clock cycle wide by assigning 14
// to the ACQPS of ADCSOCxCTL Register.
// RB2/B1
ADC_setInterruptSource(obj->adcHandle[1], ADC_INT_NUMBER1, ADC_SOC_NUMBER2);

// configure the SOCs for hvkit_rev1p1
// ISENA - PGA1->A11->RA0
ADC_setupSOC(obj->adcHandle[0], ADC_SOC_NUMBER0, ADC_TRIGGER_EPWM1_SOCA,
ADC_CH_ADCIN11, HAL_ADC_SAMPLE_WINDOW);

// ISENB - PGA3->C7->RC0
ADC_setupSOC(obj->adcHandle[2], ADC_SOC_NUMBER0, ADC_TRIGGER_EPWM1_SOCA,
ADC_CH_ADCIN7, HAL_ADC_SAMPLE_WINDOW);

// ISENC - PGA2->B9->RB0
ADC_setupSOC(obj->adcHandle[1], ADC_SOC_NUMBER0, ADC_TRIGGER_EPWM1_SOCA,
ADC_CH_ADCIN9, HAL_ADC_SAMPLE_WINDOW);

// VSENA - A2/B6/PGA1_OF (A3)->RA1
ADC_setupSOC(obj->adcHandle[0], ADC_SOC_NUMBER1, ADC_TRIGGER_EPWM1_SOCA,
ADC_CH_ADCIN2, HAL_ADC_SAMPLE_WINDOW);

// VSENB - B4/C8/PGA4_OF (B5)->RB1
ADC_setupSOC(obj->adcHandle[1], ADC_SOC_NUMBER1, ADC_TRIGGER_EPWM1_SOCA,
ADC_CH_ADCIN4, HAL_ADC_SAMPLE_WINDOW);

// VSENC - B2/C6/PGA3_OF (B3)->RC1
ADC_setupSOC(obj->adcHandle[2], ADC_SOC_NUMBER1, ADC_TRIGGER_EPWM1_SOCA,
ADC_CH_ADCIN6, HAL_ADC_SAMPLE_WINDOW);

// VSENVM - B1->RB2. hvkit board has capacitor on Vbus feedback, so
// the sampling doesn't need to be very long to get an accurate value
ADC_setupSOC(obj->adcHandle[1], ADC_SOC_NUMBER2, ADC_TRIGGER_EPWM1_SOCA,
ADC_CH_ADCIN1, HAL_ADC_SAMPLE_WINDOW);

// Vthrottle - B3->RB3. hvkit board has capacitor on Vbus feedback, so
// the sampling doesn't need to be very long to get an accurate value
ADC_setupSOC(obj->adcHandle[1], ADC_SOC_NUMBER3, ADC_TRIGGER_EPWM1_SOCA,
ADC_CH_ADCIN3, HAL_ADC_SAMPLE_WINDOW);
#endif

#if (BOOST_to_LPD == BOOSTX_to_J1_J2)
ASysCtl_selectCMPHPMux(ASYSCTL_CMPHPMUX_SELECT_3, 4); //
ASysCtl_selectCMPLPMux(ASYSCTL_CMPLPMUX_SELECT_3, 4);

ASysCtl_selectCMPHPMux(ASYSCTL_CMPHPMUX_SELECT_2, 4); //
ASysCtl_selectCMPLPMux(ASYSCTL_CMPLPMUX_SELECT_2, 4);

ASysCtl_selectCMPHPMux(ASYSCTL_CMPHPMUX_SELECT_1, 4); //
ASysCtl_selectCMPLPMux(ASYSCTL_CMPLPMUX_SELECT_1, 4);

// Configure TRIP9 to be CTRIP1H and CTRIP1L using the ePWM X-BAR
XBAR_setEPWMMuxConfig(XBAR_TRIP9, XBAR_EPWM_MUX00_CMPSS1_CTRIPH_OR_L); // Phase A
XBAR_enableEPWMMux(XBAR_TRIP9, XBAR_MUX00);

XBAR_setEPWMMuxConfig(XBAR_TRIP7, XBAR_EPWM_MUX02_CMPSS2_CTRIPH_OR_L); // Phase B
XBAR_enableEPWMMux(XBAR_TRIP7, XBAR_MUX02);

XBAR_setEPWMMuxConfig(XBAR_TRIP8, XBAR_EPWM_MUX04_CMPSS3_CTRIPH_OR_L); // Phase C
XBAR_enableEPWMMux(XBAR_TRIP8, XBAR_MUX04);

#endif

BR,
Hyu

Unless the HAL_ADC_SAMPLE_WINDOW value was significantly altered in your code, this excerpt should not impact performance, assuming that all connections are still valid.

Regards,
Jason Osborn

I'm currently using a value of 14 for HAL_ADC_SAMPLE_WINDOW in my code. What alternative values could I use?

To be clear, I was saying that it is not likely that HAL_ADC_SAMPLE_WINDOW is your issue unless you manually altered the value significantly. If the ADC input filters are equivalent on the custom board to the original reference, then the default value should be fine.

Regards,
Jason Osborn