Introduction of Fault Location, Isolation, and Service Restoration (FLISR) and Phasor Measurement Unit (PMU) Systems

Modern electric power systems face the challenge of ensuring reliable and sustainable network operation not only in normal operating conditions but also during disruptions such as changes in load parameters or emergency situations. Traditional relay protection methods based on local parameter measurements are often unable to provide rapid restoration of power supply after a disruption. Failures in protective relays, false positives, unnecessary positives lead to increased instances of power loss for unaffected consumers. Configuration changes caused by emergencies require immediate response and optimal selection of isolation points for damaged sections and adjustments to the distribution network topology during system recovery. Therefore, human factors should be considered as one of the influencing factors in errors made while managing networks under high loads and time constraints. As an option to reduce non-automatic processes in energy system management, decrease reaction times to emergency signals, determine the most acceptable options for topology changes according to predefined switching priorities, and improve reliability and speed of power restoration, we propose the integrated use of Fault Location, Isolation, and Service Restoration and Phasor measurement unit. The implementation of these technologies together will enable a comprehensive approach to managing power grid operations.