Intelligent coordinated adaptive distance relaying

•The paper presents a novel solution for distance relay third zone load encroachment problem.•A multi-agent based adaptive relaying algorithm is used to propose the solution.•The proposed algorithm was examined on radial and loop network configurations.•The results showed the superiority of the proposed algorithm in mitigating the load encroachment problem compared to traditional Mho and Quad settings.

Malfunctioning of distance relay third zone has been identified as one of the leading factors of power system blackouts in several nations. This inconsistency in operation happens when heavy loads start encroaching the zone 3 settings. In this paper, a novel multi-agent system based methodology for power system protection coordination is proposed. Various system agents are designed to collaborate and adaptively modify the setting of distance relay zone 3 via communication with neighboring substations. The proposed coordination scheme aids in preventing fault misjudgment and possible network breakdown because of load encroachment. Furthermore, it enhances the relay selectivity and loadability. It has been tested using MATLAB®/Simulink™ with the agent programming in Java Agent DEvelopment Framework (JADE) platform. Analysis and test results demonstrate that the proposed method effectively mitigates distance relay malfunction under load encroachment.