Digital twin technology for virtual testing of power system relay protection

The digitalization of the electrotechnical community brings to the natural development of digital twin replicas for various devices. In the power system protection field, digital twins for protection devices and relay test sets have been recently developed. When these two digital twins can interoperate, the highly specialized branch of the electrotechnical community, the protection of the power systems, sees the possibility to perform virtual tests of protection relays. This paper details about the today's possibilities offered by the virtual testing of power system protection relays, elaborating on the economic benefits introduced by the virtual commissioning tests, on the advantages offered on the quality of the delivered protection system and on important possibilities offered by virtual training. Subsequently the paper elaborates on the reasonable next steps for the development of this technology, from "open loop" testing to "closed loop" testing, identifying particular areas of research involvement at the academic level. Finally a view at the today's status of IEC standardization of digital twin topic is given.