Ease commissioning of a line differential scheme by sharing an Ethernet-based protection interface

Line differential protection system operators are always challenged with providing the required communications channel, i.e. the protection data interface, between the remote ends of the protection system, where the relays are installed. Nowadays most substations are equipped with network access. Leveraging such standard Ethernet-based communication for line differential protection enables for cost-effective installations. Additionally, during commissioning of line differential schemes, the protection engineers are challenged with setup and test of distributed devices in remote substations. Relays which can reuse and share a single Ethernet-based communication for relay setup, can be accessed and parameterized from a single PC connected to the protection system at one end only. The same communication channel can be reused for protection testing too. This simplifies end-to-end testing considerably, if a test system is used, which can control multiple distributed test sets for injection of voltage and current test signals from a single software on one end of the scheme. The proposed concept will ease commissioning of line differential protection systems in areas with limited reception of GPS and mobile data communication, e.g. in a tunnel or in a cavern.