The impact of saturation phenomena on over current relay in electrical intelligent network

During the past two decades, advances in technologies and protective relays structure as well as converting relays from analog to digital or intelligent, have influenced design guidelines in high voltage posts. Over current relays are the simplest ones which are capable of being structured by digital concepts. Saturation in current transformers, non-feeding, and stimulation of protective relays are along the major protective problems in power plants and high voltage posts. In this paper, through converting relays to analog or digital, we could made them intelligent against saturation in current transformers. Also, relays worked as needed.