Circulating current analysis between strands in armature winding of a turbo-generator using analytical model

In this paper, the circulating current analysis between strands is studied while considering the different transpositions in the active part and without considering the transposition in the end winding region. First, this analysis is done while only considering the slot region, and then the end winding region is added to the model. The model used for this analysis is a circuit model, including the resistance and inductance of the strands and their induced backelectromotive force (EMF). The back-EMF sources and inductances are calculated through a 2D finite element analysis (FEA) of the active part and a 3D FEA for the end winding region. For the slot region analysis, the results show that the 360◦ and 540◦ transpositions are the best. Moreover, when considering the end winding region in analysis, the results obtained show that the 540◦ transposition minimizes the circulating current more than any other transposition. Finally, for different transpositions, the obtained results are compared among themselves and with the results of the untransposed model.