Synchronization solutions for power quality functionalities in low cost smart meters

This paper aims at exploiting the functionalities of a low cost hardware to design an instrument able to detect Power Quality events with synchronization features compliant to the most severe requirements defined by the International standards. It is worth noticing that the time synchronization achievable with these devices is often not appropriately considered, but a problem in the synchronization can strongly limit the relevance and the usefulness of a multi-node measurement campaign. A solution based on NTP assisted by an external PPS signal is proposed to keep the synchronization uncertainty under the required limit also during network issues, safeguarding the low cost design.