Distance protection schemes play a vital role in ensuring reliable and speedy fault clearance on transmission lines. Directional overcurrent protection Ground distance and directional ground overcurrent relays are frequently employed to identify ground. Distance relay protection has been defined as a part of relay protection in power systems that detects and isolates faults based on the distance between the relay and fault points. Working Principle: The operation of an impedance relay hinges on the balance of voltage-induced. All distance relays compare voltages and currents to create impedance-plane and directional characteristics. Electromechanical relays do so by developing torques.