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:
\( V_S=V_R(A_1+jA_2)+I_R(B_1+jB_2) \)
\( I_S=V_R(C_1+jC_2)+I_R(D_1+jD_2) \)
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 \( V_S \) and \( I_S \) and hence the power \( P_{SO} \) absorbed from the supply by the transmission line on open circuit.
(b) If the line is modelled 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.
What I'm thinking is \( I_R=0 \) as this is an open-circuit and given \( V_R \); \( V_S \) and \( I_S \) can be calculated with matrix.
\( V_S=77325+j3149 KV \)
\( I_S=j119.9A \)
But I don't think that is correct because \( V_S \) should not be lower than \( V_R \), also 50Hz frequency is given for a reason, I'm sure it has to be used somewhere.
And as for question (b) I have only got ideas. I can find coefficient of propagation γ and \( Zo \) from R,L,G,C but I don't know how to produce them vice versa (from ABCD), I don't see where I could go from there either.
Any comments are appreciated.
\( V_S=V_R(A_1+jA_2)+I_R(B_1+jB_2) \)
\( I_S=V_R(C_1+jC_2)+I_R(D_1+jD_2) \)
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 \( V_S \) and \( I_S \) and hence the power \( P_{SO} \) absorbed from the supply by the transmission line on open circuit.
(b) If the line is modelled 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.
What I'm thinking is \( I_R=0 \) as this is an open-circuit and given \( V_R \); \( V_S \) and \( I_S \) can be calculated with matrix.
\( V_S=77325+j3149 KV \)
\( I_S=j119.9A \)
But I don't think that is correct because \( V_S \) should not be lower than \( V_R \), also 50Hz frequency is given for a reason, I'm sure it has to be used somewhere.
And as for question (b) I have only got ideas. I can find coefficient of propagation γ and \( Zo \) from R,L,G,C but I don't know how to produce them vice versa (from ABCD), I don't see where I could go from there either.
Any comments are appreciated.
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