Thermal design and analysis of a direct-water-cooled permanent-magnet synchronous generator for high-power direct-drive wind turbine applications

Abstract

As the wind turbines become larger and larger each year, more powerful and reliable generators must be designed for them. The increase of the rated power implies higher current density to achieve the acceptable dimensions for the generator. A direct-water cooling system for the stator winding of the synchronous generator ensures removal of heat losses and therefore safe temperature of the stator winding. The aim of this paper is determine the performance attributes of the cooling system of the stator winding. The design and evaluation of the cooling system are executed on the basis of analytical calculations and by using Finite Element Method.