Feeder protection relays are mainly used in overhead lines and cable lines, and are the core components of Feeder Terminal Units (FTU), Ring Main Units (RMU), and Primary Switch-gears (PSG), with the functions of protection, control, measurement, communication, data processing, power management, etc. They can be configured with a variety of distribution automation logic to realize fault detection, isolation and restoration (FDIR) of feeders, thus reducing outage time, improving power supply reliability, and helping the intelligent upgrading and transformation development of distribution networks.