Identification of Characterization Factor for Power System Oscillation Based on Multiple Synchronized Phasor Measurements

Abstract

Electric power systems in Japan are composed of remote and distributed location of generators and loads mainly concentrated in large demand areas. The structures having long distance transmission tend to produce heavy power flow with increasing electric power demand. In addition, some independent power producers (IPP) and power producer and suppliers (PPS) are participating in the power generation business, which makes power system dynamics more complex. However, there was little observation as a whole power system. In this paper the authors present a global monitoring system of power system dynamics by using the synchronized phasor measurement of demand side outlets. Phasor Measurement Units (PMU) are synchronized based on the global positioning system (GPS). The purpose of this paper is to show oscillation characteristics and methods for processing original data obtained from PMU after certain power system disturbances triggered by some accidents. This analysis resulted in the observation of the lowest and the second lowest frequency mode. The derivation of eigenvalue with two degree of freedom model brings a monitoring of two oscillation modes. Signal processing based on Wavelet analysis and simulation studies to illustrate the obtained phenomena are demonstrated in detail.GPS 2

Synchrophasor measurement based damping estimation and oscillation mode detection using FFT-CWT approach in Japan campus WAMS

“…The voltage phasor is acquired by using 96 sample data per voltage sine-wave cycle. The data is saved hourly in PMU at a certain interval of time [11], [15]. The phasor measurements from all locations are automatically transferred to the data server through the Internet.…”

Monitoring the Wide Area Power System Dynamics by Phasor Measurement Units Based on Campus WAMS Strategy

“…DYNAMICS BY PMU Figure 1 shows PMU locations in the Campus WAMS developed by our group in Japan power system, where the installations of PUMs are in the university campuses, and presently we have installed 12 PMUs: 9 of them are installed in the supply area of West Japan 60 [Hz] system and another 3 in the supply area of East Japan 50 [Hz] system (Hashiguchi T.. et al, 2008 (Tsukui, R. et al, 2001). The PMU measures the single-phase voltage phasor of 100V outlets, and corrects its clock based on the time stamp of GPS.…”

Determination of Whitening Filter Order for Estimation of Electromechanical Mode by Regression Model Representing Power System Damping Characteristics

“…As regards real-time estimation of eigenmodes using real response, our group investigated the damping effect in power systems using the power spectra of tie-line flow fluctuations and regression analysis [1,2], and eigenmode estimation based on multipoint synchronized measurement and system identification [3,4]. There have also been studies using synchronized measurement [5,6]. In addition there are techniques for estimating eigenmodes from time-series data, such as line power flow fluctuations measured at a single point, for example the Prony method [7] or whitening filters [8,9].…”