Design of Mho Type Distance Relay Scheme for Protection of Transmission Line Using EnerVista Software for D60 Relays

Transmission line network plays an important role in transferring power from Generating stations to Distribution centers and then to final users. The transmission lines are most vulnerable electrical system to faults compared to all other electrical activities. If the faults occurred on transmission lines are not identified immediately and rectified without delay may damage all the connected electrical equipment including Switches, Transformers, Generators, metering equipment etc, due to high fault currents on transmission lines. For the protection of transmission lines, IEDs can be used very effective and efficient way. With the advent of IED relays Transmission line protection has become efficient and accurate and reliable. Protection of transmission lines can also improve the reliability and dependability and security of power supply by isolating the faulty section of the network. An IED is a device that has one or more microprocessors integrated with in it. It can also communicate with other devices and systems with standard rules and protocols established and also performs many functions like protection, automation, control and metering etc. An IED can be used for protection of transmission lines by comparing currents, voltages, angles etc. This paper involves simulation of Distance protection of transmission line with various features and models with IEDs.