Differential line protection application to multi-terminal lines

The study and development of differential line protection have been undertaken by ENERTEC PSC in particular to meet the requirements of the 1986 protection plan for the EDF 400 kV network. The author describes the principles chosen for the construction of the various protection elements and gives their results and performance levels in terms of operating features: detection sensitivity for resistive faults; and stability in the presence of faults external to the system being protected