Study of a Longitudinal Flux Permanent Magnet Linear Generator for Wave Energy Converters
2006 (English)In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 30, no 14, 1130-1145 p.Article in journal (Refereed) Published
A directly coupled linear permanent magnet generator of longitudinal flux-type is investigated. The generator will be used for power take-off in a wave energy converter. A combined field- and circuit model, solved by a time stepping finite element technique, is used to model and analyse the electromagnetic behaviour of the machine. A large number of simulations form the basis of a design study where the influence of armature current level, number of cables per slot, and pole width is investigated with respect to efficiency, generator size, and the load angle. A case study is performed for a chosen generator design. The electromagnetic behaviour is examined both for nominal load and for overloads. The generator has a nominal output power of 10 kW for a constant piston speed of 0.7 m s(-1). The electromagnetic efficiency at nominal load is 86.0%, the load angle 6.6 degrees, and the power fluctuation 1.3%. At 300% overload the load angle barely exceeds 12 degrees and the cable temperature is below 25 degrees C provided that the stator back is thermally connected to the sea water. The numerical calculations have been verified for small speeds by experiments.
Place, publisher, year, edition, pages
2006. Vol. 30, no 14, 1130-1145 p.
design methodology, finite element, linear synchronous generators, permanent magnet, wave energy converter
Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-95676DOI: 10.1002/er.1209ISI: 000242188900002OAI: oai:DiVA.org:uu-95676DiVA: diva2:169985