From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001 From: priyanka Date: Wed, 24 Jun 2015 15:03:17 +0530 Subject: initial commit / add all books --- 1092/CH6/EX6.7/Example6_7.sce | 70 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100755 1092/CH6/EX6.7/Example6_7.sce (limited to '1092/CH6/EX6.7/Example6_7.sce') diff --git a/1092/CH6/EX6.7/Example6_7.sce b/1092/CH6/EX6.7/Example6_7.sce new file mode 100755 index 000000000..81d6cae8d --- /dev/null +++ b/1092/CH6/EX6.7/Example6_7.sce @@ -0,0 +1,70 @@ +// Electric Machinery and Transformers +// Irving L kosow +// Prentice Hall of India +// 2nd editiom + +// Chapter 6: AC DYNAMO VOLTAGE RELATIONS-ALTERNATORS +// Example 6-7 + +clear; clc; close; // Clear the work space and console. + +// Given data +kVA = 100 ; // kVA rating of the 3-phase alternator +V_L = 1100 ; // Line voltage of the 3-phase alternator in volt + +// dc-resistance test data +E_gp1 = 6 ; // generated phase voltage in volt +V_l = E_gp1 ; // generated line voltage in volt +I_a1 = 10 ; // full-load current per phase in A +cos_theta = 0.8 ; // 0.8 PF lagging +sin_theta = sqrt( 1 - (cos_theta)^2 ); // + +// open-circuit test data +E_gp2 = 420 ; // generated phase voltage in volt +I_f2 = 12.5 ; // Field current in A + +// short-circuit test data +I_f3 = 12.5 ; // Field current in A +// Line current I_l = rated value in A + +// Calculated data from Ex.6-4 +I_L = 52.5 ; // Rated line current in A +I_a = I_L ; // Rated current per phase in A +E_gp = 532 + %i*623 ; // Generated voltage at 0.8 PF lagging +X_s = 4.6 ; // Synchronous reactance per phase +V_p = 635 ; // Phase voltage in volt + +// Calculations +// case a +P_T = sqrt(3) * V_L * I_L * cos_theta ; // Total output 3-phase power + +// case b +P_p_b = P_T / 3 ; // Total output 3-phase power per phase + +// case c +E_gp_m=abs(E_gp);//E_gp_m=magnitude of E_gp in volt +E_gp_a=atan(imag(E_gp) /real(E_gp))*180/%pi;//E_gp_a=phase angle of E_gp in degrees + +// case d +theta = acos(0.8)*180/%pi; // phase angle for PF in degrees +theta_plus_deba = E_gp_a ; // phase angle of E_gp in degrees +deba = theta_plus_deba - theta ; // Torque angle in degrees + +// case e +P_p_e = (E_gp_m/X_s)*V_p*sind(deba); // Approximate output power/phase (Eq.(6-10)) + +// case f +P_p_f = E_gp_m * I_a * cosd(theta_plus_deba); // Approximate output power/phase (Eq.(6-9)) + +// Display the results +disp("Example 6-7 Solution : "); +printf("\n root 3 value is taken as %f , so slight variations in the answer.\n", sqrt(3)); +printf(" \n a: P_T = %d W \n", P_T ); +printf(" \n b: P_p = %.2f W \n", P_p_b ); +printf(" \n c: E_gp = %d <%.2f V \n", E_gp_m, E_gp_a ); +printf(" \n where %d is magnitude in V and %.2f is phase angle in degrees.\n",E_gp_m,E_gp_a); +printf(" \n d: Torque angle, deba = %.2f degrees \n", deba ); +printf(" \n e: P_p = %d W \n", P_p_e ); +printf(" \n f: P_p = %d W ", P_p_f ); + + -- cgit