Two-level digital relay protection system with redundancy in distribution networks
A two-level digital relay protection system has been created to significantly improve the basic properties of relay protection. The proposed system consists of a basic level and a centralized «digital substation» for each power node. It ensures the autonomy of the base level operation and the survivability of the entire relay protection system at the substation as a whole. Such a relay protection system at a «digital substation» can be implemented in stages at the facility. The two-stage principle of organizing construction, installation and commissioning works allows you to create new «digital substations» and transfer existing substations to the status of «digital substations» with minimal time. Comprehensive studies of the prototype of the protection system conducted in the laboratory and in the conditions of pilot operation confirmed the validity of the restrictions and assumptions adopted during the development.