// ELECTRICAL MACHINES // R.K.Srivastava // First Impression 2011 // CENGAGE LEARNING INDIA PVT. LTD // CHAPTER : 3 : TRANSFORMERS // EXAMPLE : 3.6 clear ; clc ; close ; // Clear the work space and console // GIVEN DATA S = 5; // Transformer Rating in kVA V1 = 220; // HV side voltage in volts V2 = 110; // LV side voltage in Volts P = 4 * 10 ^ 2; // Load of the Transformer pf = 0.8; // Power Factor (lagging) f = 50; // Frequency in Hertz // CALCULATIONS a = V1/V2; // Turn Ratio of the Transformer // case (a) At full load I1 = (S * 10 ^ 3)/V1; // Primary current at full load in Amphere I2 = (S * 10 ^ 3)/V2; // Secondary Current at full Load in Amphere // Case (b) At 4kW, 0.8 lagging pf load I11 = (4 * 10 ^ 3 * 0.8)/V1; // Primary current At 4kW, 0.8 lagging pf load in Amphere I22 = (4 * 10 ^ 3 * 0.8)/V2; // Secondary Current At 4kW, 0.8 lagging pf load in Amphere // DISPLAY RESULTS disp("EXAMPLE : 3.6 : SOLUTION :-") ; printf("\n (a) Turn Ratio of the Transformer , a = %.f \n ",a); printf("\n (b.1.1) Primary current at full load , I1 = %.2f A \n",I1); printf("\n (b.1.2) Secondary current at full load , I2 = %.2f A \n ",I2); printf("\n (b.2.1) Primary current at 4kW, 0.8 lagging pf load , I1 = %.3f A \n",I11); printf("\n (b.2.1) Secondary current at 4kW, 0.8 lagging pf load , I2 = %.3f A \n",I22);