Electric propulsion systems employs between main engine and generator engine of electric cars - engine. The mechanical energy supplied by actuators (diesel or turbine) is transformed into electrical energy using generators and mechanical energy is obtained from using propulsion motors. Because of this dual transformation of energy efficiency at rated power plant is lower than conventional propellers operated directly by the main engines.
In modern propulsion plants are used as static elements diodes, thyristors, magnetic amplifiers to obtain control features and convenient control.
Propulsion systems ordered with static elements are plants that combine the advantages of synchronous generators with DC motor, can make a shortcut in volume and restricted devices without mechanical contact, convenient features
especially for the requirements of the ship.
Static elements are used for both commands in the rotor circuit and the DC motor excitation which causes the propeller.