Overhead Line Faults Detector with Auto Trip Protection

Overhead electrical distribution lines constitute a major portion of power delivery infrastructure in developing as well as developed regions due to their economic feasibility and ease of installation. Despite their advantages, these systems are continuously exposed to environmental and mechanical stresses, making them highly susceptible to electrical faults. Fault conditions such as open conductor faults, line-to-line short circuits, and line-to-ground faults can result in serious hazards including electric shock incidents, fire accidents, equipment damage, and prolonged power outages. Rapid detection and isolation of such faults are therefore essential for ensuring safety and maintaining system reliability. This paper presents the design, simulation, and hardware implementation of a three-phase overhead line fault detection and automatic trip protection system using embedded controllers. The proposed system integrates an ESP32 microcontroller for generating balanced threephase sinusoidal pulse width modulation signals and an Arduino Mega microcontroller for continuous monitoring of voltage and current parameters. A relay-based isolation mechanism disconnects the faulty phase upon detection of abnormal electrical conditions. Additionally, a GSM communication module is incorporated to transmit real-time fault alerts to authorized personnel. The system was validated through simulation and experimental testing, demonstrating reliable fault detection performance and rapid protective action. The proposed prototype provides a scalable and cost-effective solution for enhancing safety in overhead distribution networks.