// Example 1.28 clear; clc; close; format('v',7); // Given data V0=400;//in volt f=50;//in Hz P=10;//no. of poles R1=1.75;//in ohm X1=5.5;//in ohm R2dash=2.25;//in ohm X2dash=6.6;//in ohm I0=3.8;//in Ampere W0=310;//in watts S=4;//in % //Calculations S=S/100;//slip in ratio //Formula : W0=sqrt(3)*V0*I0*cos_fi0 cos_fi0=W0/sqrt(3)/V0/I0;//power factor sin_fi0=sind(acosd(cos_fi0)); Ic=I0*cos_fi0;//in Ampere Im=I0*sin_fi0;//in Ampere Vph=V0/sqrt(3);//in Volt R0=Vph/Ic;//in ohm X0=Vph/Im;//in ohm Ns=120*f/P;//in rpm RLdash=R2dash*(1-S)/S;//in ohm R1e=R1+R2dash;//in ohm X1e=X1+X2dash;//in ohm I2rdash=Vph/(R1e+RLdash+%i*X1e);//in Ampere disp(I2rdash,"Rotor Current in Ampere : "); I0_bar=Ic-%i*Im;//in Ampere I1_bar=I0_bar+I2rdash;//Supply current in Ampere disp(I1_bar,"Supply Current in Ampere : "); cosfi=cosd(atand(imag(I1_bar)/real(I1_bar)));//Lagging power factor disp(cosfi,"Power factor(lagging) : "); Pc=3*abs(I2rdash)^2*R2dash;//in watts //Formula : P2:Pc:Pm=1:S:1-S Pm=Pc*(1-S)/S;////in watts disp(Pm,"Mechanical power devloped in N-m : "); N=Ns*(1-S);//in rpm w=2*%pi*N/60;//in rad/sec T=Pm/w;//in N-m disp(T,"Gross load tporque in N-m : ");