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-rw-r--r--3760/CH5/EX5.9/Ex5_9.sce34
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+clc;
+v=400; // rated voltage of motor
+zs=0.13+%i*1.3 ; // per phase synchronous impedance
+p=100000; // VA rating of motor
+l=4000; // stray losses
+pl=75000; // power delivered to load
+disp('case a');
+il=p/(sqrt(3)*v); // line current
+vt=v/sqrt(3); // per phase rated voltage
+pd=pl+l ; // power developed
+poh=3*il^2*real(zs);
+lt=poh+l; // total losses
+pi=pl+lt; // input power
+pf=pi/p; // power factor
+n=(1-(lt/pi))*100; // efficiency
+printf('Power factor is %f\n',pf);
+printf('Efficiency is %f percent\n',n);
+Ef1=round(sqrt((vt*pf-il*real(zs))^2+(-vt*sqrt(1-pf^2)+il*imag(zs))^2)); // excitation EMF
+de=atand((-vt*sqrt(1-pf^2)+il*imag(zs))/(vt*pf-il*real(zs)))+acosd(pf); // load angle
+printf('Excitation EMf at under excitation is %f v\n',Ef1);
+printf('Load angle at under excitation is %f degrees \n',de);
+Ef2=round(sqrt((vt*pf-il*real(zs))^2+(vt*sqrt(1-pf^2)+il*imag(zs))^2)); // excitation EMF
+de=atand((vt*sqrt(1-pf^2)+il*imag(zs))/(vt*pf-il*real(zs)))-acosd(pf); // load angle
+printf('Excitation EMf at over excitation is %f v\n',Ef2);
+printf('Load angle at over excitation is %f degrees\n',de);
+i=pi/(sqrt(3)*v);
+printf('Input current is %f A\n',i);
+disp('caes b');
+de=acosd(real(zs)/abs(zs)); // load angle
+pmax=((vt*Ef1)/abs(zs))-((Ef1^2*real(zs))/abs(zs)^2);
+pt=pmax*3;
+printf('Load angle for maximum power output is %f degrees\n',de);
+printf('Maximum output per phase is %f W\n',pmax);
+printf('Total maximum output is %f W\n',pt);