CCS/TMS320F28069M: How to change the PWM deadband falling/rising edge delay count

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Hello,

Thanks in advance for the help with this topic!

In hal.h, we define the below for the deadband.  Due to some of the modes we use our motor in, we need to update the deadband on the fly.  Is this possible?  We are using TMS320F28069M and DRV 8303.

Thanks!
Jonathan

_________________________________________________________________

//hal.h  This is where we define the deadband


//! \brief Defines the PWM deadband falling edge delay count (system clocks)

//!

#define HAL_PWM_DBFED_CNT         500 // 8205-725  8208-320

//! \brief Defines the PWM deadband rising edge delay count (system clocks)

//!

#define HAL_PWM_DBRED_CNT         500 // 8205-725  8208-320

______________________________________________________________________

//Main.c Below is a snipped where we are calling PWM functions

if(CTRL_isError(ctrlHandle)) {

            // set the enable controller flag to false

            CTRL_setFlag_enableCtrl(ctrlHandle,false);

            // set the enable system flag to false

            gMotorVars.Flag_enableSys = false;

            // disable the PWM

            HAL_disablePwm(halHandle);

        } else {

            // update the controller state

            bool flag_ctrlStateChanged = CTRL_updateState(ctrlHandle);

            // enable or disable the control

            CTRL_setFlag_enableCtrl(ctrlHandle, gMotorVars.Flag_Run_Identify);

            if(flag_ctrlStateChanged)

              {

                CTRL_State_e ctrlState = CTRL_getState(ctrlHandle);

                if(ctrlState == CTRL_State_OffLine)

                  {

                    // enable the PWM

                    HAL_enablePwm(halHandle);

                  }

                else if(ctrlState == CTRL_State_OnLine)

                  {

                    if(gMotorVars.Flag_enableOffsetcalc == true)

                    {

                      // update the ADC bias values

                      HAL_updateAdcBias(halHandle);

                    }

                    else

                    {

                      // set the current bias

                      HAL_setBias(halHandle,HAL_SensorType_Current,0,_IQ(I_A_offset));

                      HAL_setBias(halHandle,HAL_SensorType_Current,1,_IQ(I_B_offset));

                      HAL_setBias(halHandle,HAL_SensorType_Current,2,_IQ(I_C_offset));

                      // set the voltage bias

                      HAL_setBias(halHandle,HAL_SensorType_Voltage,0,_IQ(V_A_offset));

                      HAL_setBias(halHandle,HAL_SensorType_Voltage,1,_IQ(V_B_offset));

                      HAL_setBias(halHandle,HAL_SensorType_Voltage,2,_IQ(V_C_offset));

                    }

                    // Return the bias value for currents

                    gMotorVars.I_bias.value[0] = HAL_getBias(halHandle,HAL_SensorType_Current,0);

                    gMotorVars.I_bias.value[1] = HAL_getBias(halHandle,HAL_SensorType_Current,1);

                    gMotorVars.I_bias.value[2] = HAL_getBias(halHandle,HAL_SensorType_Current,2);

                    // Return the bias value for voltages

                    gMotorVars.V_bias.value[0] = HAL_getBias(halHandle,HAL_SensorType_Voltage,0);

                    gMotorVars.V_bias.value[1] = HAL_getBias(halHandle,HAL_SensorType_Voltage,1);

                    gMotorVars.V_bias.value[2] = HAL_getBias(halHandle,HAL_SensorType_Voltage,2);

                    // enable the PWM

                    HAL_enablePwm(halHandle);

                  }

                else if(ctrlState == CTRL_State_Idle)

                  {

                    // disable the PWM

                    HAL_disablePwm(halHandle);

                    gMotorVars.Flag_Run_Identify = false;

                  }

                if((CTRL_getFlag_enableUserMotorParams(ctrlHandle) == true) &&

                  (ctrlState > CTRL_State_Idle) &&

                  (gMotorVars.CtrlVersion.minor == 6))

                  {

                    // call this function to fix 1p6

                    USER_softwareUpdate1p6(ctrlHandle);

                  }

              }

        }

Hello Hareesh,

Following up on the question above to see if it is possible to adjust the deaband time on the fly?

Best,

Jonathan

Thank you Yanming Luo,

We are now able to update the deadband in real-time, but are not calling the HAL_setupPwms() function.  Does this need to also be called or can we just update via:

// setup the Dead-Band Rising Edge Delay Register (DBRED)
PWM_setDeadBandRisingEdgeDelay(halHandle->pwmHandle[0],HAL_PWM_DBRED_CNT);

PWM_setDeadBandRisingEdgeDelay(halHandle->pwmHandle[1],HAL_PWM_DBRED_CNT);

PWM_setDeadBandRisingEdgeDelay(halHandle->pwmHandle[2],HAL_PWM_DBRED_CNT);

// setup the Dead-Band Falling Edge Delay Register (DBFED)
PWM_setDeadBandFallingEdgeDelay(halHandle->pwmHandle[0],HAL_PWM_DBFED_CNT);

PWM_setDeadBandFallingEdgeDelay(halHandle->pwmHandle[1],HAL_PWM_DBFED_CNT);

PWM_setDeadBandFallingEdgeDelay(halHandle->pwmHandle[2],HAL_PWM_DBFED_CNT);

Although we are able to update on the fly, the motor at times seems unstable with the change.  Is there anything else impacted by this change that we are leaving out?

Thanks!
Jonathan