Analysis And Study Of Low-frequency Oscillations Based On Wide-area Measurements In Power Systems

With interconnection of power system, inter-area low frequency oscillation has become one of the serious factors affecting interconnected power system stability, while the application and development of wide-area measurements based on Global Positioning System (GPS) have provided a new approach for controlling of low-frequency oscillations. Based on perusing extensively referenced literature about low-frequency oscillations, wide-area measurements and researched production, the main study is as follows:1. This paper expatiates on a basic principle of low-frequency oscillations in order to present introduction comparison and existent disadvantage of some method for low frequency oscillations. With the application and development of wide-area measurement have provided a new approach for Prony method on-line low-frequency oscillations. The paper expatiates on a basic principle of Prony method and characteristic.2. The paper instructs wide-area measurements systems and analysis low-frequency oscillation by wide-area measurements and Prony method. Prony method analyzes real time data from wide-area measurements systems in order to identification low-frequency oscillations main models.3. The total damping of the power system is considered to trace of state matrix in power system. The paper states dominant damping idea. In wide-area measurement systems, when low-frequency oscillations happens and analyzes the real time data to identification the dominant low-frequency oscillations model and compute the damping of dominant low-frequency oscillations model, The dominant damping idea is to mean of the damping which is corresponding to the dominant low-frequency oscillations model. The concept of dominant damping idea is of innovation and soul of the paper. The concept is useful of on-line analysis in practical project and control low-frequency oscillations by real time data from wide-area measurement systems.4. Simulation computes total damping of systems with PSASP and MATLAB which validates the total damping.