Name of the file that implements PWM or SPWM sinusoidal modulation?s

DannyJPL · August 17, 2024, 3:04pm

Good morning, can someone please tell me the name of the file that implements the PWM or SPWM sinusoidal modulation?

Candas1 · August 19, 2024, 8:05am

Hi,

You should read the docs or use the search in github:

Antun_Skuric · August 19, 2024, 8:13am

Hey @DannyJPL,

All our FOC related code is implemented in the BLDCMotor and StepperMotor classes, in the funciton setPhaseVoltage.

For BLDC motors it’s in the src/BLDCMotor.cpp/h:

github.com

simplefoc/Arduino-FOC/blob/c72f063f3d2d2e26d49a22a7383310cf8f88134b/src/BLDCMotor.cpp#L504-L605


      
          switch (foc_modulation)
          {
            case FOCModulationType::Trapezoid_120 :
              // see https://www.youtube.com/watch?v=InzXA7mWBWE Slide 5
              // determine the sector
              sector = 6 * (_normalizeAngle(angle_el + _PI_6 ) / _2PI); // adding PI/6 to align with other modes
              // centering the voltages around either
              // modulation_centered == true > driver.voltage_limit/2
              // modulation_centered == false > or Adaptable centering, all phases drawn to 0 when Uq=0
              center = modulation_centered ? (driver->voltage_limit)/2 : Uq;
          
              if(trap_120_map[sector][0]  == _HIGH_IMPEDANCE){
                Ua= center;
                Ub = trap_120_map[sector][1] * Uq + center;
                Uc = trap_120_map[sector][2] * Uq + center;
                driver->setPhaseState(PhaseState::PHASE_OFF, PhaseState::PHASE_ON, PhaseState::PHASE_ON); // disable phase if possible
              }else if(trap_120_map[sector][1]  == _HIGH_IMPEDANCE){
                Ua = trap_120_map[sector][0] * Uq + center;
                Ub = center;
                Uc = trap_120_map[sector][2] * Uq + center;

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And for steppers it’s in the src/StepperMotor.cpp/h:

github.com

simplefoc/Arduino-FOC/blob/c72f063f3d2d2e26d49a22a7383310cf8f88134b/src/StepperMotor.cpp#L457-L468


      
          void StepperMotor::setPhaseVoltage(float Uq, float Ud, float angle_el) {
            // Sinusoidal PWM modulation
            // Inverse Park transformation
            float _sa, _ca;
            _sincos(angle_el, &_sa, &_ca);
          
            // Inverse park transform
            Ualpha =  _ca * Ud - _sa * Uq;  // -sin(angle) * Uq;
            Ubeta =  _sa * Ud + _ca * Uq;    //  cos(angle) * Uq;
          
            // set the voltages in hardware
            driver->setPwm(Ualpha, Ubeta);