Dual data aggregation for power quality assessment

The increased use of distributed energy resources and the emerging active distribution networks require new models for planning and operation of power systems. Microgrids paradigm proposes an optimal energy transfer using dedicated control algorithms and taking advantage from the ability to offer different levels of power quality. In order to achieve a real time control, a detailed model is required together with new algorithms for information retrieval. Although measurements are able to give insight to such details, the information has to be structured in a new way. Presently there are in use aggregation algorithms inherited from power quality standards like the IEC 61000-4-30 set. A discussion of the time- and space- (i.e. dual) aggregation is proposed in the paper, based on an analysis performed on local measurements in weak LV grid in Romania and MV grid with distributed generation. Data delivered by PMUs with a reporting rate of 50 frames per second is processed to highlight the effect of aggregation algorithms.