Reliability analysis of transmission lines protection systems of the SONELGAZ power system

Protection devices for electricity transmission networks are installed with the aims of protection of equipment and people and ensuring continued supply of energy. Their malfunctions can have serious consequences such as: risk for people, destruction of substations, loss of production, significant financial losses. It is therefore essential that they meet high requirements for reliability, availability and security. This paper provides an overview of the reliability of Algerian's electricity transmission network, and its evaluation that is linked with the protection system of transmission lines. For the assessment of the reliability, the characteristics of high voltage transmission lines protection are presented, along with the peculiarities in coordination and device selectivity adjustments.