The electric warship [electric propulsion]

Integrated full electric propulsion has become a normal first choice for several commercial operators, in particular for cruise ships where it proves to be a fuel efficient transmission system. Operating profiles for warships of frigate size and above are similar to cruise ships with long periods at well below full power. However the size, weight and initial cost of electric propulsion equipment has generally prevented selection for warships. With the application of modern technologies, equipment power densities are being increased such that integrated full electric propulsion has now become a serious competitor to the mechanical transmission systems traditionally adapted for warships. The authors discuss PM motor technology, power semiconductor devices (GTO, IGBT, MOS controlled thyristors), and variable speed drives.