Line differential protection over packet-switched network: performance and considerations in South Africa

Differential protection is one of the most popular protection functions utilized in the power systems for transmission lines. For differential protection to work correctly a robust communication system for receiving the current measurements and tripping information from the remote end of the line, is required. Traditionally the digital differential protection communication has been realized with protection device vendor specific proprietary communication protocols. Line differential protection is now moving from proprietary vendor specific protocol implementation to standard IEC 61850 protocol(s) and this is the first problem this paper intends to address. The second problem that this paper intends to take a stance on is that existing line differential protection methods usually use fibre…