Received voltage, transmission power system

[greg997]

Perhaps sb is able to point in the right direction. The task is to calculate the value of the receivig end volatge, for a load of 10 MW at 0.9 pf taken from 66 kV substation.
First I calculated the transmission line impedance
Zlinebase=(Vbase^2)/MVAbase
Zlinebase=132^2/100=174.24Ohm
Zlinepu= 150/174=j0.862
Sbase= 100 MVA
Load impedance = S=P+jQ
S=10+j4.84
Spu=0.1+j0.048 MVA
T1= j0.1 pu and T2= j0.12 pu
So the total impedace = T1+T2+Line+Load= j0.1+j0.2+j0.862+ 0.1+j0.048= 0.1+j1.21 ohm
Is that correct?
I know that the received volatge is Vr= Vs - Voltage drop. But how can I find the voltage drop? I need current for that, so how to find current?
Any help appreciated.According to MATLAB simulation the received voltage shoud be 57kV Line rms. Is that correct?

 

[SirAskalot]

Iteration is one simple an accurate way to solve it.

First of all refer all your values to one voltage level.

Assume 66<0 V at the load, calculate backwards to the source, compare your calculated voltage to the original source voltage. If deviation is large, do another iteration with corrected load voltage. Repeat until deviation is acceptable.

 

[greg997]

Could you please show me how to start with it? If I choose the one voltage level to be 132k then what next? And what do you mean by acceptable deviation? If I got 10900 Vs then is it acceptable?Thank you

 

[SirAskalot]

There are other methods for solving the problem. If you don't know(or have learned) this method maybe your teacher thinks of another method.

But to help you on the way. I would choose V_load = 66kV<0 at the load.

Calculate the current drawn from the load.

Then calculate the voltage at the source; V_calc = V_load + sqrt(3)* Z*I

Compare this voltage to the original source voltage (ref. 66kV) If deviation is over, let's say 5%, do another iteration.

New voltage at load is: 66kV * V_load / V_calc =

Repeat process until deviation is under "acceptable %".

A bit hard to explain in text but hope you get the picture.

 

[DeeNos]

Based on the information provided, it appears that you have correctly calculated the total impedance of the transmission line, load, and transformers. To find the voltage drop, you will need to use Ohm's law (V=IR) and calculate the current (I) based on the total impedance and the load impedance. Once you have the current, you can use it to calculate the voltage drop across the line using Ohm's law again. The received voltage (Vr) can then be calculated by subtracting the voltage drop from the supply voltage (Vs).

As for the MATLAB simulation, it is difficult to determine if the received voltage of 57kV is correct without knowing the specific parameters and assumptions used in the simulation. It would be best to double-check your calculations and compare them to the simulation results to ensure accuracy. Additionally, it may be helpful to consult with a colleague or supervisor for guidance and to verify your calculations.