Power split e-CVT solution for combined ship propulsion and electric energy generation

This paper investigates the possibility to use a power split electric Continuously Variable Transmission e-CVT as the core of a vessel power management unit which is able to produce both mechanical power for driving the propeller shafts, and electrical energy for supplying the onboard electric power system. The proposed system can be operated in three modes: full electric, full thermal and hybrid. The main feature of this system in hybrid mode is the possibility to follow two distinct set-points: one for the propeller shaft speed and one for the electric energy to be generated. The paper introduces the basic configuration and the principle of operation of the system and illustrates a case study with the description of the operating limits of the system.