State-of-the-art in the industrial implementation of protective relay functions, communication mechanism and synchronized phasor capabilities for electric power systems protection

Protective systems in electricity delivery networks have a major role to play in the increasing of renewable energy systems, and a broad understanding of their current a future application can aid into better taking them into account for achieving future energy networks that adapt for the incorporation of renewable energy generation sources. This paper provides a survey in the state of the art of protective relaying technology and its associated communications technology used in today's power transmission systems. The paper also provides the fundamental knowledge concerned with power system relaying communications. The unifying theme of this paper is to highlight that the future potential of these devices lies in realizing the possibility of going beyond their traditional application as stand-alone equipments with the single role of acting “the last line of defense” so that they can be handled with the increment of renewable energy power delivery systems in near future.