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//CHAPTER 10- THREE-PHASE INDUCTION MACHINES
//Example 4
disp("CHAPTER 10");
disp("EXAMPLE 4");
//VARIABLE INITIALIZATION
r2=0.2; //in Ohms
X2=2; //in Ohms
//SOLUTION
s_m=r2/X2;
//solution (a)
s=1;
ratio1=2/((s/s_m)+(s_m/s)); //ratio of T_starting and T_max
ratio2=2*ratio1; //ratio of T_starting and T_full-load (T_max=2*T_full-load)
disp(sprintf("(a) If the motor is started by direct-on-line starter, the ratio of starting torque to full load torque is %f",ratio2));
//solution (b)
ratio3=(1/3)*ratio2; //In star-delta starter, T_starting=(1/3)*T_starting_of_DOL
disp(sprintf("(b) If the motor is started by star-delta starter, the ratio of starting torque to full load torque is %f",ratio3));
//solution (c)
ratio4=0.7*2*ratio2; //due to 70% tapping
disp(sprintf("(c) If the motor is started by auto-transformer, the ratio of starting torque to full load torque is %f",ratio4));
//END
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