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+//Chapter 6:Induction Motor Drives
+//Example 4
+clc;
+
+//Variable Initialization
+
+//Ratings of the star connected Induction motor
+f=50           // frequency in HZ
+Vl=440         // line voltage in V
+P=6            // number of poles
+Vp=Vl/sqrt(3)  //phase voltage in V
+
+//Parameters referred to the stator
+Xr_=1.2       // rotor winding reactance in ohm
+Xs=Xr_        // stator winding reactance in ohm
+Rr_=0.4       // resistance of the rotor windings in ohm
+Rs=0.5        // resistance of the stator windings in ohm
+Xm=50         // no load reactance in ohms
+N=950         // full load speed in rpm
+Sm=2          // slip at maximum torque
+
+//Solution
+Rr_=Sm*sqrt(Rs**2+(Xs+Xr_)**2)    //Since Sm=Rr_/sqrt(Rs**2+(Xs+Xr_)**2)
+Ns=120*f/P      //synchronous speed in rpm
+Wms=2*%pi*Ns/60        
+s=(Ns-N)/Ns            //slip at 950 rpm
+
+x=%i*Xm*(Rr_/s+%i*Xr_)
+y=Rr_/s+%i*(Xr_+Xm)
+Zp=Rs+%i*Xs+x/y
+Ip=Vp/sqrt(3)/Zp    
+//The value of Ip is wrong which leads to other wrong answers
+
+Irp_=Ip*(%i*Xm)/(Rr_/s+%i*(Xr_+Xm))
+Tp=(1/Wms)*3*abs(Irp_)**2*Rr_/s
+x=%i*Xm*(Rr_/(2-s)+%i*Xr_)
+y=Rr_/(2-s)+%i*(Xr_+Xm)
+Zn=Rs+%i*Xs+x/y
+In=Vp/sqrt(3)/Zn
+Irn_=In*(%i*Xm)/(Rr_/(2-s)+%i*(Xr_+Xm))
+Tn=-(1/Wms)*3*abs(Irn_)**2*Rr_/(2-s)    
+//The value of In is wrong
+
+T=Tp-Tn
+I=abs(Ip)+abs(In)
+Rr_=0.4    // from the parameters of the motor referred to the stator
+x=sqrt((Rs+Rr_/s)**2+(Xs+Xr_)**2)
+If=(Vl/sqrt(3))/x       //full load current
+Tf=(1/Wms)*3*If**2*Rr_/s     //full load  torque
+
+ratio1=I/If
+ratio2=abs(T)/Tf
+
+//Results
+mprintf("Ratio of braking current to full load current is:%.3f",ratio1)
+mprintf("\nRatio of braking torque to full load torque is:%.3f",ratio2)
+//Answer provided in the book is wrong