Patent ID: 8198904

Claim:
A synchrophasor measuring device, comprising: a voltage measuring unit for measuring a time-series data associated with a system voltage; a frequency calculating unit for determining the amplitude, chord length and rotational phase angle of a voltage rotational vector from the time-series data obtained by the voltage measuring unit and calculating a real-time frequency; a voltage instantaneous value time-series estimation data and voltage effective value calculating unit for calculating a voltage instantaneous value time-series estimation data and a voltage effective value for estimating a sinusoidal coefficient parameter by using the real-time frequency and voltage instantaneous value time-series data of respective phase components; a synchrophasor calculating unit for calculating a synchrophasor by using the voltage instantaneous value time-series estimation data and the voltage effective value; and a voltage distortion degree calculating unit for calculating a voltage distortion degree by using the calculated synchrophasor, the voltage effective value and a voltage actually-measured value.