Methodology for Power Quality Measurement Synchronization Based on GPS Pulse-Per-Second Algorithm

Power quality disturbances (PQD) are generated by nonlinear loads and they propagate through the electrical grid to other sensitive devices causing malfunction. To study the propagation of PQD, it is important to perform synchronized and simultaneous measurements at multiple locations in the electrical network. This article proposes a methodology to synchronize measurements of electrical variables at multiple locations in the electrical grid based on the synchronization of the internal time reference of several data loggers with the pulse per second (PPS) reference provided by a global positioning system (GPS) receiver module. As the PPS signal is synchronized to the atomic clocks of the satellites in the GPS, a precise time reference in multiple sites can be obtained simultaneously. The proposed methodology has been tested in two stages. The first stage is a validation experiment that compares the number of samples obtained between three GPS synchronized data loggers and two data loggers with internal synchronization only. The PPS signal has been interrupted in one GPS synchronized data logger to simulate a signal loss and test the resynchronization capability of the methodology. A very low synchronization error has been obtained for the GPS synchronized data loggers, whereas the data loggers with the internal synchronization show greater synchronization errors. The second stage consists in experimental case of study measuring electrical variables in multiple locations of a real electrical grid where the propagation of multiple disturbances is tracked with the GPS synchronized data loggers.