Hello Clanky,
What was specific to the propulsion of SS Canberra, when compared to a pre-WWII turbo-electric ship? The electric turbo-alternators of another ship drove 3-phase motors coupled to each of the 4 propellers of this liner, the speed reduction being achieved by the number of poles and by the turbine speed.
The younger SS Canberra electric propulsion was indeed certainly much more modern, particularly concerning materials, voltage control, or even electronics.
Which ship was that?
Regards,
Luc