Checkout my post, number #11 in http://forum.arduino.cc/index.php?topic=97508.0
for the basic 3-phase PWM generation scheme using Arduino hardware counter timers.
Given a 3-phase modulator that takes an amplitude/phase input, you just have to adjust these
values in real time to get your desired waveform (ie advance the phase regularly for a sinusoid output).
That DRV10983 chip seems to have all the control logic to do this built-in, but its quite complicated -
you need to read the datasheet through several times in the first instance to get a feel for how to use it (this
is normally the case for a complex chip!).