IEC 61850-9-2 process bus and IEC 61869-9 (2016) allow Intelligent Electronic Devices (IEDs) to operate with the Sampled Values. These Sampled Values are sent by the Merging Units of digital Instrument Transformers or by the Stand Alone Merging Units (SAMU) connected to conventional Instrument Transformers.
The evolution of technology allows new approaches to voltage and current measurement in HV grids. These non-conventional instrument Transformers (NCIT) have some interesting features compared to conventional instrument transformers. ARTECHE’s optical current transformers have some differentiating features that are not only interesting for digital substation applications, but they also allow new approaches to solve challenging application scenarios such as the protection of mixed overhead-underground lines.