MustafaABB,
Just to let you know that in the past, a lot of old Electromechanical relays out there were not set using the calculated line impedance angle, and this was done in purpose.
Some of the reasons that the protection engineers did this was to add more resistive coverage on the relay...
Veritas,
Based on the 4.6km at 110KV with a SIR of 2 I do not concider this a short line. Typically a short line can be a line with a very high SIR usually above 10... and even some relay manufactures line SEL have in their relays what they called a CCVT transient compensation settings that you...
I would like to get opinions when calculating Source Impedance Ratio (SIR) on a Power System.
Usually I have seen a three Phase fault** and only taken into account the positive sequence components of the Source and divide this by the positive sequence component of the protected line.
Also, I...
