Directly-Coupled Gas Turbine Permanent Magnet Generator Sets for Prime Power Generation On Board Electric Ships

Prime power generation on board all-electric ships presents several options that affect fuel consumption, power density, operational effectiveness, and survivability. A study that aims at understanding the effects of some of these options has been conducted and results are reported in this paper. It is found that direct coupling of gas turbines to permanent magnet generators reduces system mass and volume significantly as compared to electric power generation systems installed on present-day navy ships. Furthermore, it is found that a significant benefit this topology brings is a reduction in gas turbine air duct volume if the compact gen-set units are relocated on or near the ship´s upper decks. In addition, a combinatory analysis revealed that the choice of the number of generating units and their respective power levels has a significant influence on overall efficiency.