initial commit / add all books

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+clc;

+v=2200; // rated voltage of motor

+r=0.32; // per phase armature resistance

+p=1500; // KW rating of motor

+ie=15; // exciting current

+is=750; // short circuit current

+cl=60; // core loss in KW

+fl=40; // frictional and windage loss in KW

+IF=[5 10 15 20 25 30];

+EFO=[ 760 1500 2140 2650 3040 3340]; // excitation EMF per phase

+EFP=EFO/sqrt(3);

+disp('Excitation EMF per phase(V) is');

+disp(EFP);

+// from table given for ie=15,

+Ef=2140; // Excitation EMF

+np=3; // number of phases

+ef=Ef/sqrt(3); // per phase open circuit voltage

+zs=ef/is; // synchronous impedance

+vt=floor(v/sqrt(3)); // per phase terminal voltage

+i=floor(vt/zs); // current phasor lagging vt 

+ia=vt/(2*r); // armature current

+pd=((p/2)+cl+fl)/np; // mechanical power developed per phase at half-full load output

+R=ceil(sqrt((ia^2-((pd*1000)/r)))); 

+printf('Radius of power circle is %f A\n',R);

+printf('Current phasor is %f A\n',i);

+printf('Synchronous impedance is %f ohm\n',zs);

+disp('using above data and table given in solution, V-curves and variation of p.f. with field currents can be plotted');