Influence of a Novel Stator Teeth Internal Ventilation Structure on Air-Cooled Turbo-Generator Parameters and Stator Temperature

In order to solve the problems of severe heating and cooling difficulty in the stator of air-cooled turbo-generator, a novel stator teeth internal ventilation structure with axial vents in the generator stator teeth is proposed. Based on this structure, global two-dimensional electromagnetic field models of 150MW air-cooled turbo-generator with different stator tooth internal ventilation structures are established to study the influence of the axial vents of the internal ventilation structure on air gap magnetic flux density of the generator, magnetic flux density of stator teeth, stator core loss, and synchronous reactance. Furtherly, flow network models of the ventilation system with different internal ventilation structures and fluid-heat transfer numerical models of stator with half axial and one tooth pitch of generator are established to calculate the effects of the structure on the temperature of stator winding, insulation and teeth. It can provide a new research idea for the ventilation structure of large air-cooled generator.