Analysis Of Transposition And Calculation Of Circulating Current Loss In Stator Winding Of Turbo-generator

Stator bar is one of the key components of the turbo-generator. With an increasingcapacity of turbo-generator, saturation degree is increased, leakage magneticdistribution throughout the bar is more complex, additional losses are on the increase,which respectively affect the power generation efficiency and safe operation of thegenerator. In this dissertation, numerical method for electromagnetic parameters ofthe turbo-generator stator bar of each part is adopted, by analyzing comparison ofdifferent projects, relationships and distribution laws between the Double-Roebeltransposition bar and circulating current losses of turbo-generator are found, whichprovide appropriate technical support and theoretical basis for optimization of bardesign.Firstly, a numerical method for the circulating current loss of stator bartransposition in a turbo-generator is proposed, the equivalent model ofDouble-Roebel stator bar strand transposition is constructed to achieve an effectivemodeling and simplify subdivision, strand transposition type and involute connectiontype of end winding are simulated, corresponding electromagnetic parameters of barby numerical calculations are drawn.Secondly, the influence is analyzed, which affects circulating current losses ofDouble-Roebel bar by different styles of weaving, the relationships betweentransposition types and distributions of flux density in slot centerline, current ofstrands, circulating current losses are found.Finally, the effects of circulating current losses in stator bar by several specialstructures are analyzed, corresponding changes in the relationship between them areidentified.