Protection of MHV OH-lines and cables by digital distance relays-results of laboratory tests and field experience in a Belgian MHV network

The protection of distribution networks is undergoing important technological changes and digital techniques offer now new opportunities for protection management, fault analysis and communication. Here, the authors describe the following power system protection techniques: a microcomputer-based distribution feeder (distance) relay and the new possibilities offered to operators; laboratory tests to verify better performance of digital relays for a 36 kV cable network where difficult operating conditions prevail; and remote communication between relay and user´s office. Field experience in a Belgian distribution network is also described