1 files changed, 60 insertions, 0 deletions
diff --git a/1092/CH14/EX14.20/Example14_20.sce b/1092/CH14/EX14.20/Example14_20.sce
new file mode 100755
index 000000000..5fce56316
--- /dev/null
+++ b/1092/CH14/EX14.20/Example14_20.sce
@@ -0,0 +1,60 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 14: TRANSFORMERS
+// Example 14-20
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data
+kVA = 500 ; // kVA rating of the step-down transformer
+V_1 = 2300 ; // Primary voltage in volt
+V_2 = 208 ; // Secondary voltage in volt
+f = 60 ; // Frequency in Hz
+
+// SC-test data
+P_sc = 8200 ; // wattmeter reading in W
+I_sc = 217.4 ; // Short circuit current in A
+V_sc = 95 ; // Short circuit voltage in V
+
+// OC-test data
+P_oc = 1800 ; // wattmeter reading in W
+I_oc = 85 ; // Open circuit current in A
+V_oc = 208 ; // Open circuit voltage in V
+
+// Calculations
+alpha = V_1 / V_2 ; // Transformation ratio
+// case a
+P = P_sc ; // wattmeter reading in W
+I1 = I_sc ; // Short circuit current in A
+R_e1 = P / (I1)^2 ; // Equivalent resistance w.r.t HV side in ohm
+R_e2 = R_e1 / (alpha)^2 // Equivalent resistance referred to LV side in ohm
+
+// case b
+r_2 = R_e2 / 2 ; // Resistance of low-voltage side in ohm
+
+// case c
+I_m = I_oc ; // Open circuit current in A
+P_cu = (I_m)^2 * r_2 ; // Transformer copper loss of the LV side wdg during OC-test in W
+
+// case d
+P_c = P_oc - P_cu ; // Transformer core loss in W
+
+// Display the results
+disp("Example 14-20 Solution : ");
+
+printf(" \n a: Equivalent resistance w.r.t HV side :\n    R_e1 = %.4f Ω\n",R_e1);
+printf(" \n    Equivalent resistance w.r.t LV side :\n    R_e2 = %f Ω = %.3f mΩ \n",R_e2,R_e2*1000);
+
+printf(" \n b: Resistance of LV side :\n    r_2 = %f Ω = %.2f mΩ\n",r_2,r_2*1000);
+
+printf(" \n c: Transformer copper loss of the LV side wdg during OC-test : ");
+printf(" \n    (I_m)^2 * r_2 = %f W \n",P_cu);
+
+printf(" \n d: Transformer core loss :\n    P_c = %f W \n ",P_c);
+
+printf(" \n e: Yes.The error is approximately 5/%d = 0.278 percent,which is",P_oc);
+printf(" \n    within the error produced by the instruments used in the test.");
+printf(" \n    We may assume that the core loss is %d W.",P_oc);