1 files changed, 81 insertions, 0 deletions
diff --git a/3574/CH2/EX2.5/EX2_5.sce b/3574/CH2/EX2.5/EX2_5.sce
new file mode 100644
index 000000000..5106ef12c
--- /dev/null
+++ b/3574/CH2/EX2.5/EX2_5.sce
@@ -0,0 +1,81 @@
+// Example 2.5
+// Computation of (a) Equivalent impedance of the transformer referred to the 
+// high side (b) Input impedance of the combined transformer and load (C) Actual
+// input voltage at the high side (d) Input impedance if the load is disconnected
+// (e) Exciting current for the conditions in (d)
+// Page No. 60
+
+clc;
+clear;
+close;
+
+// Given data
+S=75000;               // Transformer ratings
+VLS=240;               // Low side voltage magnitude
+PF=0.96;               // Lagging power factor
+VLS_Ang=0;             // Low side voltage angle
+VL=240;                // Load voltage
+VHS=4800;              // High side voltage
+RHS=2.488;             // High side resistance
+RLS=0.00600;           // Low side resistance
+XHS=4.8384;            // High side reactance
+XLS=0.0121             // Low side reactance
+Rfe=44202;             // High side resistance
+Xm=7798.6;             // High side reactance
+
+
+// (a) Equivalent impedance of the transformer referred to the 
+// high side 
+ILS=S*1/2/VLS;                   // Delivering one-half rated load
+Theta=acosd(PF);                 // Angle
+ThetaI=0-Theta; 
+ZloadLS_Mag=VLS/ILS;             // Low side impedance magnitude
+ZloadLS_Ang=VLS_Ang-ThetaI;      // Low side impedance angle
+
+a=VHS/VL;                       // Ratio of High side and low side voltages
+Zeq_LS=RHS+a^2*RLS+%i*(XHS+a^2*XLS)
+
+// Complex to Polar form...
+
+Zeq_Mag=sqrt(real(Zeq_LS)^2+imag(Zeq_LS)^2);            // Magnitude part
+Zeq_Ang= atan(imag(Zeq_LS),real(Zeq_LS))*180/%pi;       // Angle part 
+
+// (b) Input impedance of the combined transformer and load
+ZloadHS_Mag=a^2*ZloadLS_Mag;         // High side impedance magnitude
+ZloadHS_Ang=ZloadLS_Ang;             // High side impedance angle
+
+// Polar to Complex form
+
+ZloadHS_R=ZloadHS_Mag*cos(-ZloadHS_Ang*%pi/180); // Real part of complex number
+ZloadHS_I=ZloadHS_Mag*sin(ZloadHS_Ang*%pi/180);  // Imaginary part of complex number
+Zin=ZloadHS_R+%i* ZloadHS_I+Zeq_LS;              // Input impedance
+// Complex to Polar form...
+
+Zin_Mag=sqrt(real(Zin)^2+imag(Zin)^2);            // Magnitude part
+Zin_Ang= atan(imag(Zin),real(Zin))*180/%pi;       // Angle part 
+
+// (c) Actual input voltage at the high side
+IHS=ILS/a;                   // High side current
+VT=IHS*Zin_Mag;
+
+// (d) Input impedance if the load is disconnected 
+X=(1/Rfe)+(1/Xm*%i); 
+ZinOC=1/X;                                         // Input impedance
+ZinOC_Mag=sqrt(real(ZinOC)^2+imag(ZinOC)^2);       // Magnitude part
+ZinOC_Ang= atan(imag(ZinOC),real(ZinOC))*180/%pi;  // Angle part 
+ZinOC_Ang=ZinOC_Ang*-1;
+
+// (e) Exciting current for the conditions in (d)
+I0_Mag=VT/ZinOC_Mag;             // Magnitude of current
+I0_Ang=0-ZinOC_Ang;              // Angle of current
+
+// Display result on command window
+printf("\n Equivalent impedance of the transformer magnitude = %0.2f Ohm ",Zeq_Mag);
+printf("\n Equivalent impedance of the transformer angle = %0.1f deg ",Zeq_Ang);
+printf("\n Input impedance of the combined transformer and load magnitude = %0.2f Ohm ",Zin_Mag);
+printf("\n Input impedance of the combined transformer and load angle = %0.2f deg ",Zin_Ang);
+printf("\n Actual input voltage at the high side = %0.0f V", VT);
+printf(" \n Input impedance magnitude when load is disconnected = %0.0f Ohm",ZinOC_Mag);
+printf(" \n Input impedance angle when load is disconnected = %0.2f deg",ZinOC_Ang);
+printf(" \n Exciting current magnitude = %0.2f A",I0_Mag);
+printf(" \n Exciting current angle = %0.0f deg",I0_Ang);