ANNEX VSupplementary provisions
ANNEX V Voltage-against-time-profile referred to in Article 25 Uret Ublock Urec1 Urec2 t/sec tclear 0 trec1 trec2 1.0 U [p.u.] Figure 6 : Fault-ride-through profile of an HVDC converter station. The diagram represents the lower limit of a voltage-against-time profile at the connection point, expressed by the ratio of its actual value and its reference 1 pu value in per unit before, during and after a fault. U ret is the retained voltage at the connection point during a fault, t clear is the instant when the fault has been cleared, U rec1 and t rec1 specify a point of lower limits of voltage recovery following fault clearance. U block is the blocking voltage at the connection point. The time values referred to are measured from t fault . Voltage parameters [pu] Time parameters [seconds] U ret 0,00-0,30 t clear 0,14-0,25 U rec1 0,25-0,85 t rec1 1,5-2,5 U rec2 0,85-0,90 t rec2 T rec1 -10,0 Table 7 : Parameters for Figure 6 for the fault-ride-through capability of an HVDC converter station.