initial commit / add all books

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+clc;

+v=3300; // balanced supply voltage

+p=500000; // rated power of induction motor

+f=50; // frequency of supply

+m=3; // number of phases 

+pf=0.7; // lagging power factor

+pfn=0.9; // improved power factor

+vc=420; // rated voltage of capacitor

+n=0.86; // motor efficiency

+i=p/(sqrt(3)*v*pf*n); // line current

+i=i*(pf-%i*sqrt(1-pf^2)); // complex form of line current

+il=real(i)/pfn; // line current at improved power factor

+il=il*(pfn-%i*sqrt(1-pfn^2)); // complex form of new line current

+//from fig. 6.39 

+ic=-(imag(i)-imag(il)); // reactive component of current to be neutralised

+// capacitor bank is delta connected

+// capacitor bank is delta connected,  converting into equivalent star Xstar=Xdelta/3 

+xcd=v/(ic*sqrt(3)); // capacitance reactance

+Cd=1/(2*%pi*f*xcd*m); // capacitance

+// now each capacitor is rated at 420 V, number of capacitor connected in series is

+n=ceil(v/vc);

+C=Cd*n; 

+printf('Per phase value of each capacitance for delta connected capacitor bank is %f microfarad\n',C*10^6);

+// let R be resistance of distribution circuit

+// power lost without capacitor bank is m*abs(i)^2*R

+// power lost with capacitor bank is m*abs(il)^2*R therefore

+ps=(abs(i)^2-abs(il)^2)/abs(i)^2

+printf('Percentage saving in losses is %f percent',ps*100);