DDS - 3phase signals 120 degrees out of phase

//Disable Timer 1 interrupt to avoid any timing delays
cbi (TIMSK0,TOIE0); //disable Timer0 !!! delay() is now not available
sbi (TIMSK2,TOIE2); //enable Timer2 Interrupt

what did you mean here?

//Timer 1 setup
//Set prscaler to 1, PWM mode to phase correct PWM, 16000000/510 = 31372.55 Hz clock
void Setup_timer2()
{
// Timer2 Clock Prescaler to : 1

It seems like there's the need of some code-cleaning..

of course, other than that, that's very interesting!!