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+//Chapter 6:Induction Motor Drives
+//Example 7
+clc;
+
+//Variable Initialization
+
+//Ratings of the Star connected Induction motor
+f=50           // frequency in HZ
+Vl=2200        // line voltage in V
+P=6            // number of poles
+
+//Parameters referred to the stator
+Xr_=0.5        // rotor winding reactance in ohm
+Xs=Xr_         // stator winding reactance in ohm
+Rr_=0.12       // resistance of the rotor windings in ohm
+Rs=0.075       // resistance of the stator windings in ohm
+J=100          // combine inertia of motor and load in kg-m2
+
+//Solution
+
+//(i) During starting of the motor
+Sm=Rr_/sqrt(Rs**2+(Xs+Xr_)**2)   //slip at maximum torque
+Wms=4*%pi*f/P                     //angular frequency
+x=Rs+sqrt(Rs**2+(Xs+Xr_)**2)
+Tmax=(3/2/Wms)*(Vl/sqrt(3))**2/x  //maximum torque
+tm=J*Wms/Tmax                          //mechanical time constant of the motor
+ts=tm*(1/4/Sm+1.5*Sm)                  //time taken during starting
+Es=1/2*J*Wms**2*(1+Rs/Rr_)             //energy disspated during starting
+
+//(ii) When the motor is stopped by plugging method
+tb=tm*(0.345*Sm+0.75/Sm)        //time required to stop by plugging
+Eb=3/2*J*Wms**2*(1+Rs/Rr_)      //energy disspated during braking 
+
+//(iii)Required resistance to be inserted during plugging
+tb1=1.027*tm       //minimum value of stopping time during braking
+x=1.47*(Xs+Xr_)    //x=Rr_+Re
+Re=x-Rr_           //Re is the required external resistance to be connected
+Ee=3/2*J*Wms**2*(Re/(Re+Rr_))      //energy disspated in the external resistor
+Eb1=Eb-Ee                           //total energy disspated during braking 
+
+
+//Results
+
+mprintf("(i)Time taken during starting is ts:%.4f s",ts)
+mprintf("   \nEnergy dissipated during starting is Es:%d kilo-watt-sec",Es/1000)
+mprintf("\n\n(ii)Time taken to stop by plugging is tb:%.2f s",tb)
+mprintf("    \nEnergy dissipated during braking is Eb:%d kilo-watt-sec",Eb/1000)
+mprintf("\n\n(iii)Minimum Time taken to stop by plugging is tb:%.2f s",tb1)
+mprintf("     \nRequired external resistance to be connected is Re:%.2f ohm",Re)
+mprintf("     \nTotal Energy dissipated during braking is Eb:%.2f kilo-watt-sec",Eb1/1000)