From 7f60ea012dd2524dae921a2a35adbf7ef21f2bb6 Mon Sep 17 00:00:00 2001 From: prashantsinalkar Date: Tue, 10 Oct 2017 12:27:19 +0530 Subject: initial commit / add all books --- 3472/CH30/EX30.3/Example30_3.sce | 59 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 3472/CH30/EX30.3/Example30_3.sce (limited to '3472/CH30/EX30.3/Example30_3.sce') diff --git a/3472/CH30/EX30.3/Example30_3.sce b/3472/CH30/EX30.3/Example30_3.sce new file mode 100644 index 000000000..ac8ab68d8 --- /dev/null +++ b/3472/CH30/EX30.3/Example30_3.sce @@ -0,0 +1,59 @@ +// A Texbook on POWER SYSTEM ENGINEERING +// A.Chakrabarti, M.L.Soni, P.V.Gupta, U.S.Bhatnagar +// DHANPAT RAI & Co. +// SECOND EDITION + +// PART III : SWITCHGEAR AND PROTECTION +// CHAPTER 4: UNSYMMETRICAL FAULTS IN POWER SYSTEMS + +// EXAMPLE : 4.3 : +// Page number 512-513 +clear ; clc ; close ; // Clear the work space and console + +// Given data +kVA = 10000.0 // Alternator rating(kVA) +Z_g1 = complex(0.5,4.7) // Positive sequence impedance(ohm/phase) +Z_g2 = complex(0.2,0.6) // Negative sequence impedance(ohm/phase) +Z_g0 = complex(0,0.43) // Zero sequence impedance(ohm/phase) +Z_l1 = complex(0.36,0.25) // Impedance(ohm) +Z_l2 = complex(0.36,0.25) // Impedance(ohm) +Z_l0 = complex(2.9,0.95) // Impedance(ohm) +V = 6600.0 // Voltage(V) + +// Calculations +a = exp(%i*120.0*%pi/180) // Operator +// Case(a) +E_a = V/3**0.5 // Phase voltage(V) +Z_1 = Z_g1+Z_l1 // Z1 upto the point of fault(ohm) +Z_2 = Z_g2+Z_l2 // Z2 upto the point of fault(ohm) +Z_0 = Z_g0+Z_l0 // Z0 upto the point of fault(ohm) +I_a = 3*E_a/(Z_1+Z_2+Z_0) // Fault current(A) +// Case(b) +I_a0 = abs(I_a)/3 // Zero sequence current of line a(A) +I_a1 = abs(I_a)/3 // Positive sequence current of line a(A) +I_a2 = abs(I_a)/3 // Negative sequence current of line a(A) +I_b0 = I_a0 // Zero sequence current of line b(A) +I_b1 = a**2*I_a1 // Positive sequence current of line b(A) +I_b2 = a*I_a2 // Negative sequence current of line b(A) +I_c0 = I_a0 // Zero sequence current of line c(A) +I_c1 = a*I_a1 // Positive sequence current of line c(A) +I_c2 = a**2*I_a2 // Negative sequence current of line c(A) +// Case(c) +V_b = E_a/(Z_1+Z_2+Z_0)*((a**2-a)*Z_2+(a**2-1)*Z_0) // Voltage of the line b(V) +V_c = E_a/(Z_1+Z_2+Z_0)*((a-a**2)*Z_2+(a-1)*Z_0) // Voltage of the line c(V) + +// Results +disp("PART III - EXAMPLE : 4.3 : SOLUTION :-") +printf("\nCase(a): Fault current, |I_a| = %.f A", abs(I_a)) +printf("\nCase(b): Zero sequence current of line a, I_a0 = %.f A", I_a0) +printf("\n Positive sequence current of line a, I_a1 = %.f A", I_a1) +printf("\n Negative sequence current of line a, I_a2 = %.f A", I_a2) +printf("\n Zero sequence current of line b, I_b0 = %.f A", I_b0) +printf("\n Positive sequence current of line b, I_b1 = (%.1f%.1fj) A", real(I_b1),imag(I_b1)) +printf("\n Negative sequence current of line b, I_b2 = (%.1f+%.1fj) A", real(I_b2),imag(I_b2)) +printf("\n Zero sequence current of line c, I_c0 = %.f A", I_c0) +printf("\n Positive sequence current of line c, I_c1 = (%.1f+%.1fj) A", real(I_c1),imag(I_c1)) +printf("\n Negative sequence current of line c, I_c2 = (%.1f%.1fj) A", real(I_c2),imag(I_c2)) +printf("\nCase(c): Voltage of the sound line to earth at fault, |V_b| = %.f V", abs(V_b)) +printf("\n Voltage of the sound line to earth at fault, |V_c| = %.f V\n", abs(V_c)) +printf("\nNOTE: Changes in the obtained answer from that of textbook is due to more precision here") -- cgit