Variable frequency - ?
Many years ago a system called VSCF (variable speed, constant frequency) was proposed that used a "wild" alternator frequency, but processed this through a solid-state "chopper" to synthesize a constant-frequency output. Mechanically simple, let the electronics do the work.
I'm not sure what aircraft (if any) ever actually used this. Is it possible this is the A380 plan?
(Further research suggests Smiths and perhaps others are producing these systems)