Permanent magnet excited synchron generator, rotor defines
reference system.
The generator is directly coupled to a (passive) rectifier. If an
average-version of the rectifier is tolerable, no transforms at all
are necessary. The simulation (for linear generator models) is
fast. This is of particular importance for high speed machines,
because the high frequency drastically slows down integration in
inertial abc-system.
See for example:
ACpower.p DCpower.p DCvoltage.v