Recent Developments in Starting Cross-Compound Turbine-Generator Units

This paper develops the fundamental theory of synchronizing and loss torques in a-c machines at turming-gear speed, and shows the practical application of this theory to the synchronous starting of cross-compound turbine-generator units by the use of the shaft-position indicator and 2-speed turning-gear motors. The steam by-pass method of starting crosscompound units having shaft-driven exciters and no spare motor-driven exciter is also described.