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//CHAPTER 7- SINGLE PHASE TRANSFORMER
//Example 8
disp("CHAPTER 7");
disp("EXAMPLE 8");
//VARIABLE INITIALIZATION
va=23000; //apparent power
v1=2300; //primary voltage in Volts
v2=230; //secondary voltage in Volts
r1=4; //in Ohms
r2=0.04; //in Ohms
X1=12; //in Ohms
X2=0.12; //in Ohms
pf=0.866; //power factor(leading)
//SOLUTION
r1_dash=r1*((v2/v1)^2);
r_e2=r1_dash+r2;
X1_dash=X1*((v2/v1)^2);
X_e2=X1_dash+X2;
//
//disp(sprintf("The value of Re2 %f and Xe2 %f",r_e2,X_e2));
I2=0.75*(va/v2); //since transformer operates at 75% of its rated load
//
function [x,y]=pol2rect(mag,angle);
x=mag*cos(angle*(%pi/180)); //to convert the angle from degrees to radians
y=mag*sin(angle*(%pi/180));
endfunction;
[x,y]=pol2rect(I2,-30);
I_dash_2=x+y*%i;
//disp(sprintf("The value %f %f",real(I_dash_2),imag(I_dash_2)));
//
Z_e2=r_e2+X_e2*%i; //in rect coordinates
//disp(sprintf("The value %f %f",real(Z_e2),imag(Z_e2)));
//
V_dash_1=v2+I_dash_2*Z_e2;
//disp(sprintf("The value %f %f",real(V_dash_1),imag(V_dash_1)));
//
function [mag,angle]=rect2pol(x,y);
mag=sqrt((x^2)+(y^2)); //z is impedance & the resultant of x and y
angle=atan(y/x)*(180/%pi); //to convert the angle from radians to degrees
endfunction;
//
[magV1,angleV1]=rect2pol(real(V_dash_1),imag(V_dash_1));
//disp(sprintf("The value %f <%f",magV1,angleV1));
//
Pin=magV1*I2*cos((30+angleV1)*%pi/180);
Pout=v2*I2*cos(30*%pi/180);
eff=Pout*100/Pin;
//
disp(sprintf("The efficiency of the transformer is %f",eff));
disp(" ");
//
//END
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