Turbine-generator torsional frequencies: field reliability and testing

An extensive analytical and experimental program was launched to investigate torsional phenomena occurring in turbine-generator (T-G) units and to determine their effects on unit availability. Broader knowledge in the area of machine/system interactions, acquired by power system planners and T-G designers as a result of this Westinghouse effort, is already contributing toward increased generating unit availability. The analytical and experimental tools used in the calculation and measurement of torsional characteristics of T-G units are described in some detail. (LCL)