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//CHAPTER 8- DIRECT CURRENT MACHINES
//Example 21
disp("CHAPTER 8");
disp("EXAMPLE 21");
//10kW 6 pole DC generator
//VARIABLE INITIALIZATION
p_o=10*1000; //in Watts
P=6; //number of poles
E_g=200; //in Volts
N=1500; //in rpm
A=P; //since the armature is lap connected
B=0.9; //flux density in Tesla
l=0.25; //length of armature in m
dia=0.2; //diameter of armature in m
//SOLUTION
//solution (a)
//pole pitch is defined as the periphery of armature divided by the number of poles or the area of armature between two adjacent poles
//area of armature = 2.pi. dia of armature. length of armature
area=2*%pi*(dia/2)*l; //area of armature
phi=B*area; //flux density over one pitch pole= flux per pole/area of armature between poles
disp(sprintf("(a) The flux per pole is %.4f Wb",phi));
//solution (b)
Z=(60*E_g)/(phi*N); // no of conductors in the armature
//induced emf = phi.Z.N.P/60.A
// = phi.Z.N/60 ( as A=P)
disp(sprintf("(b) The total number of active conductors is %d",Z));
//solution (c)
I_a=50; // armature current
p=E_g*I_a; //power developed
w=(2*%pi*N)/60; //speed in RPS
T=p/w; //Torque
disp(sprintf("(c) The torque developed when armature current is 50 A is %.2f N-m",T));
//END
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