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diff --git a/3760/CH5/EX5.53/Ex5_53.sce b/3760/CH5/EX5.53/Ex5_53.sce
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+clc;
+m=3; // number of phases
+p=2; // number of poles
+P=4*10^6; // rated power of generator
+v=11000; // rated voltage of generator
+as=72; // armature slots
+cs=4; // conductor per armature slot
+rs=24; // rotor slots
+rp=10; // rotor slot angular pitch
+cr=20; // conductors per rotor slot
+z=0.1+2*%i; // armature leakage impedance per phase
+pf=0.8; // lagging power factor
+vt=v/sqrt(3); // terminal voltage
+ia=P/(sqrt(3)*v); // full load armature current
+// Open circuit characteristics have been plotted using table given in question.Per phase value of  excitation voltage is obtained fron table
+IF=[ 40 80 120 160 200 240 280 320 360];
+EA=[ 2490 4980 7470 9390 10620 11460 12030 12450 12660 ];
+plot(IF,EA/sqrt(3));
+xlabel('Field current');
+ylabel('open circuit voltage');
+title('open circuit characteristics');
+Er=vt+ia*(pf-%i*sqrt(1-pf^2))*z; // air gap voltage
+printf('Air gap voltage is %f V\n',abs(Er));
+disp('Corresponding to magnitude of air gap voltage value of field MMF in terms of field current is obtained from O.C.C  (for textbook refer fig. 5.114)');
+Fr=242; // field MMF in terms of field current
+q=rs/p; // rotor slots per pole
+kd=sind(q*rp/2)/(q*sind(rp/2)); // distribution factor
+kp=1 ; // coil span factor for full pitch field coil
+kw=kd*kp; // winding factor
+Nf=(rs*cr)/p; // total field turns
+F1f=(4*kw*Nf)/(%pi*p); // ratio of fundamental field mmf per pole to field current
+Nph=(as*cs)/(m*p); // series turn per phase
+q1=as/(m*p); // armature slots per pole per phase
+v1=(p*180)/as; // armature slot angular pitch
+kd=(sind(q1*v1/2))/(q1*sind(v1/2)); // distribution factor
+kw=kd*kp; // winding factor
+Fa=(0.9*m*Nph*ia*kw)/(p*F1f); // armature mmf in terms of field current
+B=acosd(pf)+atand(imag(Er),real(Er)); // power factor angle + angle by which air gap voltage leads terminal voltage 
+Ff=sqrt(Fr^2+Fa^2-2*Fr*Fa*cosd(90+B)); // equivalent field current
+printf('Equivalent field current is %f A\n',Ff);
+// corresponding to equivalent field current, excitation voltage is obtained from O.C.C
+Ef=7168; // excitation EMF per phase
+vr=((Ef-vt)/vt)*100; 
+printf('Voltage regulation at full load %f lagging power factor is %f percent',pf,vr);