initial commit / add all books

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+clc

+// Variable Initialization 

+Vm=230//Supply Voltage in Volts

+Ra=0.5//Armature circuit resistance in Ohm

+Irms=25 //Armature current in Amp

+Nr=800 //Motor speed in Rpm

+Kaf=0.172 //Motor Voltage Constant in V/rpm

+a=60//firing angle in Degree

+

+//Solution

+//CASE:A

+//For motoring action

+Ka=(Kaf*60)/(2*%pi)//Constant in V-s/rad

+T=Ka*Irms //Torque of motor in N-m

+Va=(2*Vm*1.414)*cosd(a)*(1/%pi)//Average voltage in Volts

+Eb=Va-(Irms*Ra)//Back Emf in Volts

+N=Eb/Kaf//Speed of motor in Rpm

+//The supply current is square wave if motor current is constant and ripple-free with Amplitude 25A

+P=Vm*Irms //Supply VA in Watt

+//Power from supply is real power if losses in converter are neglected

+Ps=Va*Irms //Power in Watt

+pf=Ps/P //Power factor lag

+

+//CASE:B

+//For polarity reversal (regeneration action)

+Eb1=-Eb //Back emf in Volts

+Va1=Eb1+(Irms*Ra)

+af=acosd((Va1*%pi)/(2*Vm*1.414))//Firing angle in Degree

+//Power fed from DC Machine

+Pdc=Eb*Irms //Power in watt

+//Power  lost in armature resistance

+PL=((Irms)^2)*Ra //Power in Watt

+//Power fed back to ac supply is

+PF=Pdc-PL //Power in watt

+

+//Results

+printf('\n\n The motor Torque=%0.1f N-m \n\n',T)

+printf('\n\n The motor Speed  =%0.1f RPM \n\n',N)

+printf('\n\n The Supply Power Factor=%0.1f Lag\n\n',pf)

+printf('\n\n The Firing Angle=%0.1f Degree\n\n',af)

+printf('\n\n The Power fed back to Supply=%0.1f Watt\n\n',PF)

+//The answers vary due to round off error