clc,clear printf('Example 3.13\n\n') V=240 P_out=25*735.5 //output power in watts R_a=0.14,R_sh=80 //resistance of armature and shunt field winding brush_drop=1 //voltage drop across brush I_L_FL=95 //input current at full load I_sh=V/R_sh I_a_FL = I_L_FL - I_sh //armature current at full load arm_cu_loss_FL = R_a*I_a_FL^2 //full load armature copper loss field_cu_loss= R_sh*I_sh^2 //field copper loss printf('(i)Armature and field copper losses are %.2f W and %.0f W respectively\n',arm_cu_loss_FL,field_cu_loss) brush_cu_loss= 2*brush_drop*I_a_FL //brush contact copper loss printf('(ii)Brush contact copper loss is %.0f W\n',brush_cu_loss) E_b=V-I_a_FL*R_a - 2*brush_drop //back emf gross_mech_P_dev= E_b*I_a_FL //gross mechanical power developed IFW_losses = gross_mech_P_dev - P_out //iron friction and windage losses printf('(iii)Core plus mechanical losses = %.1f W\n',IFW_losses+field_cu_loss+arm_cu_loss_FL) eta=100*(P_out/(P_out + IFW_losses+ brush_cu_loss+field_cu_loss+arm_cu_loss_FL )) printf('(iv)Efficiency is %.2f percent',eta)