Figure 3a shows a 50 Hz, high-voltage transmission line

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Spongecake
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Homework Statement


Figure shows a 50 Hz, high-voltage, transmission line. The relationships between the sending and receiving end voltages and currents are given by the complex ABCD equations:

mimetex-cgi-20v_s-v_r-a_1-ja_2-i_r-b_1-jb_2-gif.gif


mimetex-cgi-20i_s-v_r-c_1-jc_2-i_r-d_1-jd_2-gif.gif


where 'S' stands for sending-end and 'R' stands for receiving-end

(a) Given the parameter values in TABLE C and an open-circuit received voltage measured as 88.9 kV, calculate the values of
mimetex-cgi-20v_s-gif.gif
and
mimetex-cgi-20i_s-gif.gif
and hence the power
mimetex-cgi-20p_-so-gif.gif
absorbed from the supply by the transmission line on open circuit. Vs= 77.33kv + J3147.06v Is= 0 + j119.93 A P= 377.43kW

(b) If the line is modeled by the T-circuit of FIGURE 3(b), see if you can estimate the primary line coefficients R, L, G and C. The line is 50 km long.

Homework Equations


formulae-png.png


The Attempt at a Solution


Regarding part b) this is what I have at the moment but not sure I am doing it correctly.
A= 0.8698+J0.03542 B= 47.94+J180.8 C= 0+J0.001349 D= 0.8698+J0.03542
This means that A and D a symmetrical A=D.
I don't really know where to go from here as I have looked at other posts on this question and they don't seem to make much sense due to lots of people asking several different questions.
 

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Also Z1= Z3 =1/2 (R+jωL)δx and Y2= (G+jωC)δx Where δx= line length.
But I don't know how to get from the matrix to Z1, Z3 and Y2