Power system dynamic performance measured by phasor measurement unit

In recent years, there has been an increasing interest in monitoring and analyzing dynamic performances of power systems, such as observation of power system oscillations and evaluation of machine parameters. However, in Japan, 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. Authors have placed phasor measurement units (PMU) connected to 100V outlets in some universities in Japan and been researching into oscillation characteristics in power systems. Phasor measurements are synchronized based on the global positioning system (GPS) and measurement data are transmitted via Internet Some oscillative features and variation of phasor in a day, a week or a year are analyzed using the acquired data. The purpose of this paper is to show a power system dynamic performance by the use of measurement data at an unexpected disturbance and monitors a global and a local oscillation mode.