Voltage Based Phase Identification Method, Robustness and Validation

One of the problems of full-scale utilization of per phase measured smart meter data is the uncertainty whether phase labeling between different metering locations belongs to the same actual phase. This uncertainty poses a risk that the measured data might be misinterpreted. This problem has been addressed by introducing many different phase identification methods which one of these, voltage based, is investigated in this paper. The function of this method was tested on a real deployed measurement that should have represented scenario of smart meter measurements. To investigate the method performance a 45 days worth of high resolution (200 ms samples) voltage measurement have been collected and later postprocessed by the proposed method. To further explore the method robustness, the analysis included different method settings and also the influence of different measurement accuracy. To obtain greater certainty of the obtained results, the phase connection of all deployed measuring units has been unified by very accurate signal injection phase identification method. From the obtained results it is found out, that the proposed method can be quite prone to worse performance for cases with lower measurement accuracy with the overall phase identification probability being more than 80 %. To stay in the more robust performance region it is recommended to search for voltage events with higher magnitudes and use longer aggregation intervals (e.g. 10 minutes).