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// Variable Declaration
MVA_G1 = 20.0 //MVA rating of generator 1(MVA)
kv_G1 = 13.2 //Voltage rating of generator 1(kV)
x_G1 = 0.14 //Reactance of generator 1(p.u)
MVA_T1 = 20.0 //MVA rating of transformer 1(MVA)
kv_T1_lv = 13.2 //L.V voltage rating of transformer 1(kV)
kv_T1_hv = 132.0 //H.V voltage rating of transformer 1(kV)
x_T1 = 0.08 //Reactance of transformer 1(p.u)
MVA_G2 = 30.0 //MVA rating of generator 2(MVA)
kv_G2 = 13.2 //Voltage rating of generator 2(kV)
x_G2 = 0.16 //Reactance of generator 2(p.u)
MVA_T2 = 30.0 //MVA rating of transformer 2(MVA)
kv_T2_lv = 13.2 //L.V voltage rating of transformer 2(kV)
kv_T2_hv = 132.0 //H.V voltage rating of transformer 2(kV)
x_T2 = 0.12 //Reactance of transformer 2(p.u)
x_L = 75.0 //Line reactance(ohm)
// Calculation Section
MVA_base = 45.0 //Base MVA
kv_lv_base = 13.2 //L.T base voltage(kV)
kv_hv_base = 132.0 //H.T base voltage(kV)
I_lt_base = MVA_base*1000/(3**0.5*kv_lv_base) //Base current on LT side(A)
x_G1_new = x_G1*(MVA_base/MVA_G1) //New reactance of generator 1(p.u)
x_G2_new = x_G2*(MVA_base/MVA_G2) //New reactance of generator 2(p.u)
x_T1_new = x_T1*(MVA_base/MVA_T1) //New reactance of transformer 1(p.u)
x_T2_new = x_T2*(MVA_base/MVA_T2) //New reactance of transformer 2(p.u)
x_L_new = x_L*(MVA_base/kv_hv_base**2) //New line reactance(p.u)
V_f = 1.0 //Pre-fault voltage at fault point FF(p.u)
x_T = (x_L_new/2)+((x_G1_new+x_T1_new)*(x_G2_new+x_T2_new)/(x_G1_new+x_T1_new+x_G2_new+x_T2_new)) //Thevenin reactance(p.u)
I_f = V_f/complex(0,x_T) //Fault current(A)
I_G1 = I_f*(x_G2_new+x_T2_new)/(x_G1_new+x_T1_new+x_G2_new+x_T2_new) //Fault current shared by generator 1(p.u)
I_f_G1 = I_G1*I_lt_base //Fault current shared by generator 1(A)
I_G2 = I_f*(x_G1_new+x_T1_new)/(x_G1_new+x_T1_new+x_G2_new+x_T2_new) //Fault current shared by generator 2(p.u)
I_f_G2 = I_G2*I_lt_base //Fault current shared by generator 2(A)
// Result Section
printf('Fault current fed by generator 1 = %.1fj A' ,imag(I_f_G1))
printf('Fault current fed by generator 2 = %.1fj A' ,imag(I_f_G2))
printf('\nNOTE : ERROR : MVA ratings of G2 & T2 are 30 MVA , not 25 MVA as in textbook question')
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