An IEC 61850 Sampled Values-based Analyzer for Power Quality applications on Smart Substations

This paper introduces a system capable of characterizing on-site digital instrument transformers from the analysis of the IEC 61850/IEC 61869-9 frames injected by the Stand Alone Merging Units (SAMU) located in digital substations. Besides, exploiting the interesting feature of being able to calculate the Power Quality (PQ) from the information sent by the SAMU, the second objective of this work is to implement a suitable computation architecture to monitor distributed PQ nodes. In a first step, this approach relies on the implementation of a IEC 61000-4-30 class-A PQ library on an industrial-based computer. Later, the library is migrated to a more limited platform to identify the maximum number of parallel nodes that the analyzer can process. Several experimental tests were carried out to verify the suitability of the proposed solution. The excellent results of the calibration by comparison between the digital instrument transformer and the analogue reference transformer and the number of parallel nodes that the system can analyze  indicate that the proposed low-cost analyzer meets the stringent class-A requirements of the IEC 61000-4-30 for real-time evaluations.