Hey guys
I'm trying to work out this question, using an equivalent Pi circuit, but that fact that it is a "double circuit" is confusing me.
Here is the background.
A 3-Phase, 50Hz, 330kV, 360MW at 0.82 PF is supplied by:
-330kV, 50Hz, Length (L) = 160km, 3-Phase double circuit.
Each circuit has per-phase
Resistance (R) = 120x10^-6 per-unit/km
Reactance (X) = 990x10^-6 per-unit/km
Shunt Susceptance to Neutral (jB) = 461.7x10^-3 per-unit/km
Neglecting Shunt Conductance.
All units have been given in Vbase = 330kV, Sb = 100MVA
So what I think so far:
Because its a balanced and double
-both transmission line circuits will have the same voltage and current
-Thus we can calculate perimeters of just one line
But -The receiving current will be multiplied by two
Can I do these things?
Dose this effect the values used for each line impedance and the Shunt Susceptance?
With the Pi network
Z(line) = L x(R + jB)
=160((120x10^-6)+j(990x10^-6))
Do I need to convert this from phase resistance
I understand I may also need to determine the load impedance and add this to the line impedance for the equivalent circuit.?
What do you guys think?
thanks heaps
I'm trying to work out this question, using an equivalent Pi circuit, but that fact that it is a "double circuit" is confusing me.
Here is the background.
A 3-Phase, 50Hz, 330kV, 360MW at 0.82 PF is supplied by:
-330kV, 50Hz, Length (L) = 160km, 3-Phase double circuit.
Each circuit has per-phase
Resistance (R) = 120x10^-6 per-unit/km
Reactance (X) = 990x10^-6 per-unit/km
Shunt Susceptance to Neutral (jB) = 461.7x10^-3 per-unit/km
Neglecting Shunt Conductance.
All units have been given in Vbase = 330kV, Sb = 100MVA
So what I think so far:
Because its a balanced and double
-both transmission line circuits will have the same voltage and current
-Thus we can calculate perimeters of just one line
But -The receiving current will be multiplied by two
Can I do these things?
Dose this effect the values used for each line impedance and the Shunt Susceptance?
With the Pi network
Z(line) = L x(R + jB)
=160((120x10^-6)+j(990x10^-6))
Do I need to convert this from phase resistance
I understand I may also need to determine the load impedance and add this to the line impedance for the equivalent circuit.?
What do you guys think?
thanks heaps
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