Principles of combined drive control
Electric Ship. New Concepts, Power Control Systems, Design Constraints

Please also refer to paragraph 2.2 of article [D 5 610] .

The concept of the coupled alternator was at the origin of this solution. The idea was to use a certain amount of energy available on the shaft line to power the on-board networks. The idea of using this alternator as a back-up engine soon emerged, followed by the idea of combined propulsion.

As the main propulsion system was based on a diesel engine or turbine, it was possible to provide additional electrical power from the on-board grid:

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