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+//Book Name: Fundamentals of electrical drives by Mohamad A. El- Sharkawi
+//chapter 7
+//example 7.4
+//edition 1
+//publisher and place:Nelson Engineering
+clc;
+clear;
+V=480;//terminal voltage in volt
+p=6;//number of poles
+f=60;//frequency in hertz
+Tout=300;//constant load torque in Nm
+N1=1;
+N2=1;
+Prot=1e3;//rotational power in watt
+alpha=120;//trigerring angle in degree
+mprintf("\nTo find speed of the motor:")
+a=120;//constant value
+ns=(a*f)/p;
+n=ns*(1+((N1/N2)*cosd(alpha)));
+mprintf("\nThe speed of the motor is %f rpm",n)
+s=(ns-n)/ns;
+mprintf("\nTo compute current in DC link:")
+rps=n/60;//speed in rps
+omega=(2*%pi*rps);
+Pout=Tout*omega;
+Pd=Pout+Prot;
+K=(3*sqrt(2))/%pi;
+I=(Pd/(1-s))/(K*V);
+mprintf("\nThe current in DC link is %f A",I)
+mprintf("\nTo compute rotor rms current:")
+itr=sqrt(2/3);//solved integration value
+I2=itr*I;
+mprintf("\nThe rotor rms current is %f A",I2)
+mprintf("\nTo compute stator rms current:")
+I1=(N1/N2)*I2
+mprintf("\nThe stator rms current is %f A",I1)
+mprintf("\nTo compute power returned to the source:")
+Pr=Pd;
+Pr=Pr*10^(-3);
+mprintf("\nThe power returned to the source is %f watt",Pr)
+mprintf("\nTo compute the losses when additional resistance is added:")
+Td=Pd/omega;
+rpss=ns/60;//speed in rps
+omegas=(2*%pi*rpss);
+Radd=(V^2*s)/(Td*omegas);//additional resistance added in ohm
+I2=sqrt(((s/(1-s))*(Pd/3))/Radd);//rotor current
+Padd=3*I2^2*Radd;//additional power loss
+Padd=Padd*10^(-3);
+mprintf("\nThe power losses when additional resistance added is %f watt",Padd)