Design and Analysis of an Over Current Relay Based on MATLAB/Simulink Environment

The work aims to develop and comprehensively analyze an advanced overcurrent relay system for protecting power transmission networks. Overcurrent relays are critical components used either as main protection relays or as backup protection relays in the power transmission protection system. The primary function of these relays is to trip and disconnect the faulty circuit whenever the current exceeds a pre-defined threshold limit or pre-set current value. Ensuring the safety and reliability of electrical power systems heavily relies on the accuracy and performance evaluation of overcurrent relays. As a result, the design and simulation evaluation are conducted using the powerful MATLAB/Simulink platform. This paper presents an in-depth investigation into the design and performance assessment of an overcurrent relay, utilizing the MATLAB/Simulink simulation environment. By evaluating its effectiveness under various fault scenarios, including L-G (Line-to-Ground), L-L-G (Line-to-Line-Ground), and L-L-L-G (Line-to-Line-to-Line-Ground) faults with varying fault locations, the relay’s accuracy, selectivity, and response speed are comprehensively examined.