After enumerating a number of advantages of electrical drive for the propellers of ships with Diesel or gas-turbine main engines, and briefly discussing some reasons why these transmission systems are not more generally used, the Author (of Marinetechnik Planungsgesellschaft, Hamburg) presents some results of a joint study, by several organisations, on these systems in the light of new developments in electrical equipment. The objective was to ascertain the extent to which the advantages of these electrical propulsion installations outweigh their higher cost, and whether they are likely to become more widely used. Four different system concepts were studied, three for a large ship and one for a small vessel:--(i)a 2 x 20-MW propulsion system with watercooled a.c. asynchronous propeller-motors (ii)a 2 x 20-MW propulsion system with permanently-excited synchronous propeller-motors; (iii)a 2 x 20-MW propulsion system with superconducting d.c. unipolar propeller-motors; (iv)a 2 x 1-MW propulsion system with permanently-excited synchronous propeller-motors. The study showed that, for the electrical transmission system in the 2 x 20-MW ship, a weight/power ratio of not more than about 2.3 to 2.8 tonnes/MW can be expected in the future, as compared with 7 tonnes/MW today. Volume as well as weight would be reduced, and cost would be between 300,000 and 540,000 DM/MW, the lightest design 1 MW per shaft, weight/power ratio would be about 5.3 tonnes/MW, compared with about 15 tonnes/MW for a conventional electrical transmission; cost would be about 1.3 million DM/MW. Taking into consideration that c.p. propellers would not be necessary, and that the ship's mains could be supplied from the propulsion installation, electrical transmission designed on these new concepts would not cost much more than geared installations. Order from BSRA as No. 52,317.

  • Availability:
  • Corporate Authors:

    Seehafen-Verlag Erik Blumenfeld

    Celsiusweg 15, Postfach 1347
    2000 Hamburg 50,   Germany 
  • Authors:
    • Schacht, J
  • Publication Date: 1979-10


  • German

Media Info

  • Features: References;
  • Pagination: p. 863
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00310791
  • Record Type: Publication
  • Source Agency: British Ship Research Association
  • Files: TRIS
  • Created Date: May 7 1980 12:00AM