diff options
Diffstat (limited to '1445/CH8/EX8.22/Ex8_22.sce')
| -rw-r--r-- | 1445/CH8/EX8.22/Ex8_22.sce | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/1445/CH8/EX8.22/Ex8_22.sce b/1445/CH8/EX8.22/Ex8_22.sce index 7a554a6c8..5adaef446 100644 --- a/1445/CH8/EX8.22/Ex8_22.sce +++ b/1445/CH8/EX8.22/Ex8_22.sce @@ -1,10 +1,10 @@ //CHAPTER 8- DIRECT CURRENT MACHINES //Example 22 +clc; disp("CHAPTER 8"); disp("EXAMPLE 22"); -//230 V 600 rpm shunt motor //VARIABLE INITIALIZATION N1=600; //in rpm v=230; //in Volts @@ -16,12 +16,12 @@ drop=2; //brush drop in Volts //SOLUTION //solution (i) -I_l2=5; // no load current -I_a1=I_l1-(v/r_f); // armature current -E_b1=v-(I_a1*r_a)-drop; // back emf +I_l2=5; +I_a1=I_l1-(v/r_f); +E_b1=v-(I_a1*r_a)-drop; I_a2=I_l2-(v/r_f); E_b2=v-(I_a2*r_a)-drop; -N2=(E_b2/E_b1)*N1; // speed at no load +N2=(E_b2/E_b1)*N1; N2=round(N2); disp(sprintf("(i) The speed at no load is %d rpm",N2)); @@ -32,17 +32,16 @@ E_b2=(N2/N1)*E_b1; dif=v-drop; //difference I_a2=I_l2-(v/r_f); r_se=((dif-E_b2)/I_a2)-r_a; -disp(sprintf("(ii) The additional resistance is %.3f Ω",r_se)); +disp(sprintf("(ii) The additional resistance is %f Ω",r_se)); //solution (iii) -//Eb1/Eb2 = phi2.N2/Phi1.N1 phi1=1; //it is an assumption I_a3=30; N2=750; E_b3=v-(I_a3*r_a)-drop; phi2=(E_b3/E_b1)*(N1/N2)*phi1; red=((1-phi2)*100*phi1)/phi1; -disp(sprintf("(iii) The percentage reduction of flux per pole is %.1f %%",red)); +disp(sprintf("(iii) The percentage reduction of flux per pole is %f %%",red)); //END |