A thermal model for the water-cooled stator bars of the synchronous generator

The paper presents a thermal model of the water-cooled stator bars in a large synchronous generator using the equivalent thermal network method. A stator bar is studied, the copper strands and cooling water are divided into elements simultaneously and the temperature of cooling water is also calculated. Then, simple element and more elements analysis methods are used to calculate the temperature of stator bars. A stator bar of a QFQS-200-2 turbo-generator is computed with the proposed methods. The calculated and the measured results are analyzed and the proposed method is validated to be correct.