initial commit / add all books

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+clc,clear

+printf('Example 3.7\n\n')

+

+I_1=40 //motor input current

+V=200  //voltage across armature

+I_2=32  //load current

+V_2=160  //voltage across generator

+V_f=15 //voltage drop across field windings

+total_input = (V+V_f)*I_1  

+Output=V_2*I_2

+total_losses = total_input-Output   //total losses in 2 machines

+

+R_se=V_f/I_1   //series field resistance

+R_a=0.4 // armature field resistance

+

+total_cu_loss=(R_a + 2*R_se) * I_1^2 + I_2^2*R_a //total copper loss

+stray_losses =  total_losses -  total_cu_loss

+stray_losses_each =stray_losses /2 //stray losses for each machine

+

+//for motor

+motor_input= V*I_1

+arm_cu_loss= (R_a + R_se)*I_1*I_1 //armature copper loss

+total_losses_motor = arm_cu_loss +  stray_losses_each 

+motor_output= motor_input- total_losses_motor

+eta_m=100*motor_output/motor_input //efficiency of motor

+printf('Efficiency of motor is %.2f percent \n',eta_m)

+//for generator

+arm_cu_loss_gen=R_a*I_2^2 //armature copper loss

+series_field_cu_loss = V_f*I_1 //series field copper loss

+total_losses_gen= arm_cu_loss_gen +  series_field_cu_loss + stray_losses_each 

+generator_input = total_losses_gen+ Output

+eta_gen=100*Output/generator_input //efficiency of generator

+printf('Efficiency of generator is %.2f percent',eta_gen)

+printf('\n\nAnswer dont match because Output-of-generator is taken as 5220 for calculation while its should have been 5120')