A comparative study of tripping and reclosing schemes for six-phase transmission line considering transient stability

This paper discusses the feasibility of three-phase switching of six-phase lines for single phase-to-ground faults as a protection scheme. To apply such scheme, it is necessary that the transient stability, extinction of secondary arc current, thermal duty of nearby generators and torsional torques induced on the shaft of turbine-generators are investigated and compared with single-pole switching scheme. Transient stability is the most important concern in switching of lines. Therefore, in this paper, the transient stability of the three-phase switching of six-phase lines as well as the single-phase switching scheme is simulated and the results are compared. The results can be used to make decision about choosing the suitable six-phase transmission line protection scheme.