The application of Hilbert-Huang transform in power quality detection?

According to the characteristics of transient power quality disturbances, the Hilbert-Huang transform is used for the analysis of power quality disturbance signal, its core is to carry the empirical mode decomposition(EMD) on the power quality disturbances, directly produce the intrinsic mode function(IMF) from the signal itself and each intrinsic mode function can ensure the single value of the instantaneous frequency function, then perform the Hilbert transform and least squares in each intrinsic mode function, after that the instantaneous frequency spectrum can be obtained. The simulation results show that the intrinsic mode function is obtained after the empirical mode decomposition first time, and the instantaneous frequency spectrum shows that the power disturbances occur starting and ending time, and the characteristics of different transient disturbance signal can be obtained through determining the amplitude and frequency of each intrinsic mode function.