Coordination of time-overcurrent relays for high-speed power line protection

A properly coordinated protection system is essential to ensure that an electricity distribution network can operate within its requirements, regarding the safety of a power system. Automatic operation is necessary to isolate faults on a power system in a minimum time. The study of time coordination of relays suggests improved ways of power line protection. The protection must be sensitive enough to operate when a fault occurs under minimum fault conditions, yet be stable enough not to operate when its associated equipment is carrying the maximum rated current, which may be a short-time value. A power system is used as an example of time coordination of distance relays that are responsible for clearing any possible faults. The communication of the protection relays is associated with the backup protection which is responsible for covering the failure of the main protection system. In addition, the reliability of the power system is improved by establishing the right relay communication and settings