D1 - Report on the realisation of a reference SAMU with up to 96 kSPS sampling rate and up to c. 40 kHz bandwidth

This document outlines the development of several reference devices used for the calibration of Stand-Alone
Merging Units (SAMUs) that are used in the electricity grid. The ongoing transformation of the grid, driven by
the integration of renewable energy sources, necessitates the use of SAMUs for further control and automation
of the electricity grid. However, there are currently no services available to calibrate these merging units, and
the lack of dedicated reference equipment hinders progress. Reliable calibration and testing starts with
traceability (derived) from National Metrology Institute (NMI) level. Accredited test and calibration laboratories
need verification of the accuracy of their equipment from an NMI. The focus is on the reference devices used
in calibration facilities and their technical requirements for magnitude and timing accuracy evaluation. Other
aspects like latency of goose messaging and synchronization problems are not part of this project. The
document identifies key substation devices that can be calibrated using a reference SAMU, including other
merging units, non-conventional instrument transformers, and test bridges.