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.

Table 7: Parameters for Figure 6 for the fault-ride-through capability of an HVDC converter station.