Question

**4.** The three phase 400kV transmission line is
180km long. The end-of-line voltage is 410 kV and the load is 400
MVA with a power factor of 0.8 ind. The cable parameters are: r =
0.026 Ω / km, x = 0.33Ω / km, g = 0.023µS / km and b = 3.57µS / km.
Calculate the cable transfer constants A, B, C, and D using the
appropriate modeling method. Use a + i * b syntax for your
answers.

Enter the displacement constant A.

Enter the transfer constant B.

Give the transfer constant C in the micro, i.e. 10 ^ -6.

digits (e.g. 12*10 ^ -6)

Enter the transfer constant D.

(Give the answer of accuracy of at least three to five significant digits.)

Answer #1

1- A 69-kV, three-phase short transmission
line is 16 km long. The line has a per
phase series impedance of 0.125 +
j0.4375 ohm per km. Determine the sending
end voltage, voltage regulation, the
sending end power, and the transmission
efficiency when the line delivers
a. 70 MVA, 0.8 lagging power factor at 64 kV
b. 120 MW, unity power factor at 64 kV
2-three-phase, completely transposed 345-kV, 200 km
line has two 795,000-
cmil 26/2 ACSR conductor per bundle...

1- 30-kV, three-phase transmission line has a per
phase series impedance of z = 0.05+j0.45 ohm per Km and a per phase
shunt admittance of y = j3.4x10-6
siemens per km. The line is 80 km long.
Using the nominal π
model, determine
a The transmission line ABCD constants.
b Find the sending end voltage and current,
voltage regulation, the sending end power
and the transmission efficiency when the line
delivers
1. 200 MVA, 0.8 lagging power factor at 220...

A 100 km long, three phase 50 hz transmission line has
resistance per phase per km of 0.1 ohms, reactance per phase per km
of 0.5 ohms, susceptance per phase per km of 10 x 10-6 siemens. If
the line supplies a load of 20 MW at 0.9 pf lagging at 66 KV at the
receiving end, calculate the regulation and efficiency of the line
using the following assumptions:
a. nominal pi vector solution
b. nominal T vector solution
c....

A 250 km , three- phase , 50 Hz transmission line is delivering
25 MVA at 0.8 lagging power factor to a balanced load at 132 KV (
line-line) . The conductor resistance is 0.11 ohm/km . The line
inductance per phase is 1.24 mH/km and the line to neutral
capacitance is given as 9.4 x 10 – 9 F/km.
a ) find the nominal – Л representation.
b) find the sending end voltage , VS by nominal – Л...

A three-phase 12-mile, 50 kV (line), 60 Hz line has a resistance
of 0.1, capacitance of 0.01 and inductance of 1 mH/km. The load at
the receiving end of the line absorbs 10 MVA at 90 percent of rated
voltage. Calculate:
ABCD parameters of the line
The sending-end voltage if the load power factor is 0.8
lagging.
The sending-end line voltage, line current and complex power if
the load has a power factor of 0.7 leading.

Problem 2. A three phase transformer rated at 5 MVA, 115/13.2 kV
has a per phase series impedance of 0.007 + j0.075 per unit (shunt
parameters are ignored). The low voltage side is connected to a
short distribution line which modeled by a series per phase
impedance of 0.02 +j0.1 per unit on the base of 10 MVA. The line
supplies a balanced three phase constant impedance load at 4 MVA,
13.2 kV with power factor of 0.85 lagging
•...

The generalized circuit constants (ABCD) of a 345 kV
transmission line are given as:
A = D = 0.82 + j0.019
B = 40 +j150 ohm
C = (-1.35 + j193.3) x 10-6 S
Do this problem using the per unit system. Hint: The sending end
power and voltage will make good base values.
a) At the sending end, the transmission line is delivering 400
MVA at 0.8 pf at the rated voltage. Find the receiving end voltage
and current...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 3 minutes ago

asked 8 minutes ago

asked 18 minutes ago

asked 36 minutes ago

asked 45 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago