Development of Temperature Calculation for Armature Windings of Turbine Generators with Circulating Currents and Strands Transposition

In this study, we describe a temperature calculation method with a large network solver for transposed armature windings of a turbine generator. As is well known, a significant amount of circulating current flows within strands in armature bars. Therefore, it is critical that physical transposition of the strands should be considered for temperature calculation. We developed a calculation tool that can extensively handle the circulating current as well as complicated temperature distribution of the cooling media in the generator. The calculated result indicates that temperature distribution in generators can have a wide range as opposed to detectable temperatures depending on the design.