Abstract :
THE calculation of shaft and frame stresses in turbine generators during short circuits or synchronizing is dependent upon a knowledge of the electrical torque developed at the rotor air gap. This torque generally contains unidirectional, fundamental-frequency, and second-harmonic components, all of which are damped. It is the steady components of torque which are of interest in the calculation of system stability, while all the components are of interest to the turbine generator designer.