Chyzhevskyi V. Real-time evaluation of a menace of power union's oscillating instability

The dissertation for the scientific degree of Candidate of technical sciences in the specialty 05.14.02 - electrical power plants, networks and systems. - National Technical University of Ukraine "Kyiv Polytechnic Institute", Ministry of Education and Science of Ukraine, Kyiv, 2016. In this thesis an approach to the solution of actual scientific and technical problem of real-time evaluation of a menace of power union's oscillating instability due to arising of low frequency oscillations (LFO) is proposed. This approach based on using of specially prepared ensemble of signals' analysis methods for processing of results of synchronized measuring of power union's state parameters. With complex of requirements the selection of methods for real-time identification of LFOs' parameters is made. Necessity of using of power system stabilizers with settings adopted to the actual frequency values of LFOs' dominant modes for increasing of reliability of LFOs' damping in LFOs' integrated damping system is found out. Using of ensemble of previously selected signals' analysis methods for reliable real-time evaluation of a menace of power union's oscillating instability is proposed for the first time. The procedure for generalization of parameters estimation results of LFOs' dominant modes obtained from the proposed ensemble of signals' analysis methods is developed. Increasing of the precision and estimation reliability of the parameters of LFOs' dominant modes by means of using of instantaneous values of the signal and digital filtering of the signals before their processing with the ensemble of signals' analysis methods is experimentally proved. Keywords: power union, low frequency oscillations, stability, damping, signals' analysis methods.