Analysis of transient stability swings in large interconnected power systems by Fourier transformation

A novel technique to analyze transient stability program swing curves is developed which uses the Fourier transformation. This approach generalizes the swing characteristics to specific frequency components over the range of time. The frequency components of the power system swings are identified in the frequency spectrum. These components can then be selected for further analysis. The mathematical process to determine the amount of damping in the respective frequency components is outlined. The damping constants can be obtained by comparing the magnitudes of the respective frequency components in different time windows. Good correlations of the results with conventional linear eigenvalue analysis have been observed. Advantages and necessary precautions in applying the method are presented