High-speed generators for power dense, medium power, gas turbine generator sets

摘要

What is not presently available to ship designers is a gas turbine power plant in a medium power range (10 -14 MW). Sixty-three generator concepts over four different generator types - air-cooled wound field, liquid-cooled wound field, permanent magnet (PM), and high-temperature superconducting (HTS) - are evaluated with three different ship-level electrical system architectures - high-frequency AC distribution, active rectified and passive rectified. A prime mover of 14 MW and 7000 rpm is assumed. The study assesses generator size enabled by directly coupling the generator to the prime mover, eliminating the typical gear required in T-G sets with engine speeds greater than 3600 rpm. Technology approaches are described and trends in the design data are identified. More advanced technologies utilizing permanent magnets and superconducting rotor coils are evaluated, but for the power range, speed range and system requirements, the best of these designs do not significantly differ from the water-cooled design in size and weight. Conclusions indicate that a water-cooled generator would be compatible with a range of future distribution systems. The watercooled generator will be capable of operating with either a higher frequency AC distribution system, a DC distribution system (using a rectifier), or a 60 Hz AC system (using a rectifier and inverter). With power density similar to a superconducting machine, and a greater flexibility of application than a permanent magnet machine, the water-cooled design was selected for further development.