Enhancing Overcurrent Relay Coordination to Address Power System Operational and Topological Changes

The reliable operation of power distribution systems critically depends on coordinating its protection devices to safeguard against electrical faults and ensure system stability. With the increasing adoption of distributed generators and formation of microgrids, achieving robust, effective, and resilient coordination becomes a formidable challenge; it is important that there is an emphasis on grid protection because of reasons such as increased fault current, bi-directional fault current, increased meshness of the distribution network, frequent changes in network topology, and frequent changes in network operations. This paper presents an approach aimed at enhancing overcurrent relay coordination to address these specific challenges. By analyzing the issue of miscoordination caused by changes in both operational and network topology due to line outages or fault isolation, this paper adopts a methodology that adapts relay settings to mitigate miscoordination. The approach utilizes K-Means clustering to group various operational and topology scenarios and uses a modified Time Current Curve equation making the coordination system responsive to both operational and network topology changes. The research results demonstrate a significant improvement in the reliability and robustness of overcurrent relay coordination, even under challenging and dynamic operational conditions. By fostering adaptability and flexibility in the face of evolving operational and network topology, the findings contribute to the improvement of overcurrent relay coordination viz-a-viz advancement of power system protection and reliability.