Arduino three phase inverter code

 int pinU = 3;  // PWM pin for U phase

int pinV = 5;  // PWM pin for V phase

int pinW = 6;  // PWM pin for W phase

void setup() {

  pinMode(pinU, OUTPUT);

  pinMode(pinV, OUTPUT);

  pinMode(pinW, OUTPUT);

}

void loop() {

  // Sinusoidal wave generation for phase U

  for(int i=0;i<256;i++){

    int value = sin((i*2*PI)/256)*127+128;  // calculate the sine wave value

    analogWrite(pinU, value);  // set the PWM value

    delayMicroseconds(1000);   // wait for 1ms

  }

  // Sinusoidal wave generation for phase V

  for(int i=0;i<256;i++){

    int value = sin(((i+85)*2*PI)/256)*127+128;  // calculate the sine wave value with 120 degree phase shift

    analogWrite(pinV, value);  // set the PWM value

    delayMicroseconds(1000);   // wait for 1ms

  }

  // Sinusoidal wave generation for phase W

  for(int i=0;i<256;i++){

    int value = sin(((i+170)*2*PI)/256)*127+128;  // calculate the sine wave value with 240 degree phase shift

    analogWrite(pinW, value);  // set the PWM value

    delayMicroseconds(1000);   // wait for 1ms

  }

}

This code uses the Arduino's built-in analogWrite() function to generate three-phase PWM signals with sinusoidal waveforms. The sin() function is used to calculate the sine wave values for each phase, with appropriate phase shifts between them to create a three-phase waveform. The PWM duty cycle is varied to control the output voltage level. This code can be modified to suit your specific three-phase inverter application.