Dynamic Measurement of the Absolute Voltage Angle on Long Transmission Lines

A new apparatus for dynamic measurement of the absolute voltage angle on long transmission lines is described. It is based on a method of synchronization by satellite and takes 30 measurements per second at three points of the Hydro-Québec network on a permanent basis. The system gives the local (or absolute) voltage phase angle (using a 60.00-Hz reference frame), the frequence at each point and the angle difference-between each pair of points. Automatic recordings of this data are made during disturbances.