Reply by mnentwig September 1, 20072007-09-01
Your phasors rotate at f=50 or 60 Hz? You could downconvert them to 0 Hz by
multipliying with exp(-i 2 pi f t) and lowpass filter.
In the complex plane you can then see how frequency behaves (1 forward
rotation per second: Frequency is 1 Hz too high etc).


Reply by Bessie September 1, 20072007-09-01
What other methods can be used to analyse power system oscillations from
phasor measurements besides FFT and Wavelet?