Figure 3.3-4 The directional logic diagram
The directional mode can be selected with the 67P_Dir_Mod setting. The user can select either
"(Non-Dir)", "(Forward)" or "(Reverse)" mode. By setting the value of 67P_Dir_Mod to "0", the
non-directional operation is allowed when the directional information is invalid.
Where
:
67P_Dir_Mod is a direction mode setting for 67P.
The 67P_RCA setting is used to turn the directional characteristic. The value of 67P_RCA should
be chosen in such a way that all the faults in the operating direction are seen in the operating zone
and all the faults in the opposite direction are seen in the non-operating zone. The value of
Characteristic angle depends on the network configuration.
The cross-polarizing quantity is used to determine the fault direction(Iaïƒ Ubc/Ibïƒ Uca/Icïƒ Uab).
The evaluation of the forward directionality is according to the equation: