1 files changed, 57 insertions, 0 deletions
diff --git a/1445/CH2/EX2.28/ch2_ex_28.sce b/1445/CH2/EX2.28/ch2_ex_28.sce
new file mode 100644
index 000000000..1b48dddce
--- /dev/null
+++ b/1445/CH2/EX2.28/ch2_ex_28.sce
@@ -0,0 +1,57 @@
+//CHAPTER 2- STEADY-STATE ANALYSIS OF SINGLE-PHASE A.C. CIRCUIT
+//Example 28 // read it as example 27 in the book on page 2.80
+
+disp("CHAPTER 2");
+disp("EXAMPLE 28");
+
+//VARIABLE INITIALIZATION
+z1=2+(%i*3);                    //impedance in rectangular form in Ohms
+z2=1-(%i*5);                    //impedance in rectangular form in Ohms
+z3=4+(%i*2);                    //impedance in rectangular form in Ohms
+v=10;                           //in volts
+//SOLUTION
+
+//solution (a)
+//Total impedance
+//Total circuit impedance Z=(Z1||Z2)+Z3
+z=z1+(z2*z3)/(z2+z3);
+disp("SOLUTION (i)");
+disp(sprintf("Total circuit impedance is %3f %3fj S", real(z), imag(z)));
+//Total supply current I=V/Z
+//solution (b)
+i=v/z;
+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;
+[mag, angle]=rect2pol(real(i), imag(i));
+disp("SOLUTION (b)");
+disp(sprintf("Total current is %f<%f Amp",mag,angle));
+//solution (c)
+//Vbc=I.Zbc where Zbc=(z2*z3)/(z2+z3)
+Vbc=i*((z2*z3)/(z2+z3));
+[mag1, angle1]=rect2pol(real(Vbc), imag(Vbc));
+disp("SOLUTION (c)");
+disp(sprintf("The voltage across the || circuit is %f<%f",mag1, angle1));
+disp(sprintf("The voltage Vbc lags circuit by %f Deg",angle-angle1));
+//solution (d)
+//i2=Vbc/z2, i3=Vbc/z3
+i2=Vbc/z2;
+i3=Vbc/z3;
+[mag2, angle2]=rect2pol(real(i2), imag(i2));
+[mag3, angle3]=rect2pol(real(i3), imag(i3));
+disp(sprintf("The current across fist branch of || circuit is %f<%f",mag2, angle2));
+disp(sprintf("The current across second branch of || circuit is %f<%f",mag3, angle3));
+//solution (e)
+pf=cos(-1*angle*%pi/180);
+disp("SOLUTION (e)");
+disp(sprintf("The power factor is %f",pf));
+//solution (iv)
+//Apparent power s=VI, True Power, tp I^2R, Reactive Power, rp=I^2X or VISSin(angle)
+s=v*mag;
+tp=mag*mag*real(z);
+rp=v*mag*sin(-1*angle*%pi/180);
+disp("SOLUTION (f)");
+disp(sprintf("The Apparent power is %f VA, True power is %f W , Reactive power is %f vars",s,tp,rp));
+disp(" "); 
+//END