AbstractA mathematical analysis Is developed to Include the saturation In the small-perturbation equations of synchronous machines. The saturation in both the d-and q-axls has been considered. Using this model, the effect of saturation on both the synchronizing and damping torque coefficients (KSand KD) has been investigated for various loading conditions. The results have been verified by comparing them with those of an ai.alog computer simulation and with those of published work.