Identifying inter-area oscillations using Hilbert-Huang trasformation for improving damping through PSS

Abstract

Hilbert-Huang transform (HHT) is applied to wide area measurement system (WAMS) data in order to identify inter-area oscillations present in the system. HHT is used to extract instantaneous frequency of multicomponent signal using Empirical Mode Decomposition (EMD) and Hilbert transform. Upon identification of oscillatory modes, these oscillations are damped through power system stabilizers (PSS) connected to the exciters of the generators. Conventional PSS uses a local signal like generator speed deviation or real power output deviation. Here, two signals have been considered for PSS. The first signal is local signal that is the speed deviation of the generator at which PSS is connected. The second signal is a global signal. Several global signals have been tested. The global signals used are the remote rotor speed deviations, tie-line real power and voltage magnitude. The proposed method has been applied to two-area test system and the simulation results are presented.

Coordinated design of PSS and unified power flow controller using the combination of CWT and Prony methods with the help of SPEA II multi‐objective optimisation algorithm

“…This method is useful to identify the signal features in time and frequency domains and estimating the damping ratio and the frequency of modes, and the mode shape. The proper formulations and guidelines for the selection of mother wavelet function, centre frequency parameter, bandwidth parameter, translation factor, and scaling factor are very momentous [25][26][27][28].…”

“…The controller transfer function can be acquired and the parameters of PSS and UPFC will be computed when appropriate Δλ m are chosen, [28,30].…”

“…One of the recursive methods is autoregressive moving average eXogenous (ARMAX) method that was applied to ambient data for the first time [26]. Recursive maximum likelihood method [27], Hilbert-Huang transform method [28], and ITD-RDT method [29] are other notable methods. In several papers, the application of these methods including the controllers' design, transient stability, and small-signal stability and voltage stability analysis was appraised [30][31][32][33][34][35].…”