Machiavelli999
Active member
It's a pretty bad sign that I am having trouble with a problem this close to the exam, but...
I have no idea how they get system thevanen impedance of 0.025 pu, which they use to find the fault current.
I got a completely different answer.
SCD = 40 MVA
Voltage = 12.47kV
Zth = 12.47kV^2 / 40MVA = 3.88 ohms
Then I divide it by 40 to bring it down to a base of 1,000 kVA and I get Zth = 0.09719 pu.
How do they get Zth = 0.025 pu???
I have no idea how they get system thevanen impedance of 0.025 pu, which they use to find the fault current.
I got a completely different answer.
SCD = 40 MVA
Voltage = 12.47kV
Zth = 12.47kV^2 / 40MVA = 3.88 ohms
Then I divide it by 40 to bring it down to a base of 1,000 kVA and I get Zth = 0.09719 pu.
How do they get Zth = 0.025 pu???