High-power Generators for Offshore Wind Turbines

In offshore wind energy conversion system, the dominant technology is the geared drive train with induction generator, and high-power generators are preferred with respect to cost and energy production. However, simply upscaling the conventional design will normally lead to low efficiency, heavy top head mass and expensive machine. The main objective of this paper is to investigate the technological challenges related to the high-power generators for offshore wind turbines. In the first part of this paper, the generator technologies in the global operational offshore wind farms are reviewed; in the second part, the relationships of generator active/supporting mass vs. power are obtained by doing machine optimization with the finite element method and the genetic algorithm. The solutions for high-power generators are reviewed and discussed finally.