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3 years ago

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A two-bus power system is interconnected by one transmission line. Bus 1 is a generator bus with specified terminal voltage magn

itude of |V1| pu. We desire to solve the power flow problem for this system.
a. Identify the variables in the solution vector assuming Bus 2 is a load bus with specified demand as PD pu and QD pu.
b. Identify the variables in the solution vector assuming Bus 2 is a PV bus.

1 answer:

mixas84 [53]3 years ago

7 0

Answer:

a) | v2 | , β2 ( load, bus voltage at bus 2 )

p1 , q1 ( slack, bus power at bus 1 )

b) q2 , β2

p1 and q1 ( slack, bus power at bus 1 )

Explanation:

Attached below is a schematic representation of the solution

<u>a) Identify the variables in the solution vector assume Bus 2 is a load bus</u>

The specified parameters are ; P2 and q2

while | v2 | and β2 are not specified

given that bus 2 is a load bus, bus 1 is a slack bus with ; | v1 | and β1 been specified while p1 and q1 are not specified

<em>Hence the variables in the solution </em>

<em>= | v2 | , β2 ( load, bus voltage at bus 2 )</em>

<em> p1 , q1 ( slack, bus power at bus 1 ) </em>

<u>b) Identify the variables in the solution vector ( assume Bus 2 is a PV bus )</u>

specified at Bus 2 are ; | p2 | , | v2 |

unspecified : q2 , β2

Bus 1 ( still a slack bus )

specified parameter : | v1 | and β1

unspecified : p1 and q1

<em>Hence the variables in the solution </em>

<em>= q2 , β2 </em>

<em> p1 and q1 ( slack, bus power at bus 1 ) </em>

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Answer:

Part a: The volume of vessel is 4.7680 $m^3$ and total internal energy is 3680 kJ.

Part b: The quality of the mixture is 90.3% or 0.903, temperature is 120 °C and total internal energy is 4660 kJ.

Explanation:

Part a:

As per given data

m=2 kg

T=80 °C =80+273=353 K

Dryness=70% vapour =0.7

<em>From the steam tables at 80 °C</em>

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Now the relation of total specific volume for a specific dryness value is given as

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Substituting the values give

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The total internal energy is 3680 kJ.

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Part b

Volume of vessel is given as 1.6

mass is given as 2 kg

Pressure is given as 0.2 MPa or 200 kPa

Now the specific volume is given as

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Specific internal energy =u=2330 kJ/kg

The total internal energy is given as

$u=\frac{U}{m}\\U=u \times m\\U=2330 \times 2\\U=4660 kJ$

So the quality of the mixture is 90.3% or 0.903, temperature is 120 °C and total internal energy is 4660 kJ.

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Answer:

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Minimum stress level =σ₂

The mean stress given as

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By adding the above equation

2 σ₁ = 530.4

σ₁ = 265.2 MPa

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