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diff --git a/3760/CH5/EX5.1/Ex5_1.sce b/3760/CH5/EX5.1/Ex5_1.sce
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+clc;
+v=220; // rated voltage of alternator
+f=50; // frequency of supply
+r=0.06; // resistance per phase
+p=6; // number of poles
+i=40; // full load current 
+pf=0.8; // lagging power factor
+vt=v/sqrt(3); // rated per phase voltage
+IF=[ 0.2 0.4 0.6 0.8 1 1.2 1.4 1.8 2.2 2.6 3 3.4];
+EA=[ 29 58 87 116 146 172 194 232 261.5 284 300 310];
+subplot(313);
+plot(IF,EA/sqrt(3));
+xlabel('Field current');
+ylabel('open circuit voltage');
+title('open circuit characteristics');
+IF1=[ 0.2 0.4 0.6 0.8 1 1.2 1.4 1.8 ];
+ISC=[ 6.6 13.2 20 26.5 32.4 40 46.3 59 ];
+subplot(323);
+plot(IF1,ISC);
+xlabel('Field current');
+ylabel('short circuit current');
+title('short circuit characteristics');
+ZPF=[ 0 0 0 0 0 0 29 88 140 177 208 230];
+subplot(333);
+plot(IF,ZPF);
+xlabel('Field current');
+ylabel('terminal voltage');
+title('full load zero power factor characteristics');
+disp('EMF method');
+// value of synchronous reactance is taken from given table
+EA1=[ 29 58 87 116 146 172 194 232]
+ZS=EA1./(ISC*sqrt(3));
+disp('synchronous impedance (ohms) is');
+disp(ZS);
+XS=ZS; // RS^2 is negligible
+disp('synchronous reactance (ohms) is');
+disp(XS);
+xs=2.27;
+ia=i*(pf-%i*sqrt(1-pf^2)); // full load current in complex form
+E=vt+ia*(r+%i*xs); // Excitation voltage
+vr=floor(((abs(E)-vt)/vt)*100); 
+printf('Voltage regulation is %f percent\n',vr);
+disp('Mmf method');
+// with ia as reference
+E=vt*(pf+%i*sqrt(1-pf^2))+i*r; // Excitation voltage
+// from fig 5.30 ,E=127 V
+oc=1.69; // current for given excitation voltage obtained from open circuit characteristics
+sc=1.2; // field current required to circulate full load short circuit current
+al=atand(imag(E),real(E)); // angle between ia and E
+Ff=(oc*(-sind(al)+%i*cosd(al)))-sc; // field mmf
+printf('field mmf is %f A\n',abs(Ff));
+// corresponding to Ff,E=163.5 v from O.C.C
+Ef=163.5; 
+vr=((Ef-vt)/vt)*100; 
+printf('Voltage regulation is %f percent\n',vr);
+disp('Zero power factor method');
+// As per the description given in method
+vd=30; // voltage drop armature leakage reactance
+xa=vd/i; // armature leakage reactance
+// with ia as reference
+Er=vt*(pf+%i*sqrt(1-pf^2))+i*(r+%i*xa); // Excitation voltage
+// from fig 5.30 ,E=148.6 V
+oc=2.134; // current for given excitation voltage obtained from open circuit characteristics
+Fa=0.84; // armature mmf from potier triangle
+be=atand(imag(Er),real(Er)); // angle between ia and E
+Ff=(oc*(-sind(be)+%i*cosd(be)))-Fa; // field mmf
+printf('field mmf is %f A\n',abs(Ff));
+// corresponding to Ff=2.797 A,E=169 v from O.C.C
+Ef=169; 
+vr=((Ef-vt)/vt)*100;
+printf('Voltage regulation is %f percent\n',vr);
+disp('New A.S.A method');
+// parameters needed in this method are calculated in part c
+id=0.366; // difference in field current between OCC and air gap line from fig 5.30
+th=acosd(pf);
+ig=1.507; // field current corresponding to rated rated per phase voltage
+Ff=ig+sc*(%i*pf+sqrt(1-pf^2)); // field mmf without saturation
+Ff=abs(Ff)+id; // ield mmf with saturation
+printf('field mmf is %f A\n',Ff);
+// corresponding to Ff=2.791 A,E=169 v from O.C.C
+Ef=169; 
+vr=((Ef-vt)/vt)*100;
+printf('Voltage regulation is %f percent\n',vr);
+disp('Saturated synchronous reactance method');
+// for E=148.5 v (from part c), 
+Era=179.5; // air line gap voltage
+k=Era/abs(Er); // saturation factor
+vdg=100.5; // voltage drop in unsaturated synchronous reactance
+xag=vdg/i; // unsaturated synchronous reactance
+xas=xa+((xag-xa)/k); // saturated synchronous reactance
+// with vt as reference
+Ef=vt+ia*(r+%i*xas); 
+ok=2.15; // resultant mmf from fig 5.30
+Ff=(abs(Ef)/abs(Er))*ok;
+printf('field mmf is %f A\n',Ff);
+// corresponding to Ff=2.78 A,E=169 v from O.C.C
+Ef=169; 
+vr=((Ef-vt)/vt)*100;
+printf('Voltage regulation is %f percent\n',vr);