Wams-based Power System Low-frequency Oscillation Online Identification

This paper takes power system low-frequency oscillations control and low-frequency oscillations pattern recognition as the main study object and following works are performed:1.Expounds basic principles of low-frequency oscillations and cites basic method of low-frequency oscillations.It also introduces wide-area measurement system based on PMU and two kinds of signals analysis:Prony Method and HHT Method.2.Proposes a new power system low-frequency oscillations pattern recognition method based on the HHT Method and demonstrates feasibility of the method.3.Demonstrates advantages of the HHT Method for low-frequency oscillation pattern recognition.HHT Method can be used directly to replace the actual system of Prony Method,and can be applied to the online identification of low-frequency oscillations.4.Analyzes the method of suppression of the low-frequency oscillations and proposes a framework of on-line analysis of low-frequency oscillations using wide-area measurement system and HHT Method.