Problem 103 A dc series motor is supplied by 250 Vdc and run

Problem 10.3
A dc series motor is supplied by 250 Vdc, and runs at 600 rpm. The armature resistance is 1.1 , and the field winding resistance is 0.8 . The motor constant is 0.75 V.s/A.
Calculate the output power.

Problem 10.5
A dc shunt generator charges a battery. The battery voltage is 12 V, the required charging current is 50 A. The generator shunt winding resistance is 20 and the armature resistance is 0.05 The generator speed is 800 rpm. In open circuit conditions the generator input current is 5 A.
Calculate the required input power.

Solution

supply voltage v=250 volts

speed N=600 rpm

armature resistance=1.1 ohms

field resistance=0.8 ohms

motor constant=0.75 v-sec/amp

we know motor equation

v=Eb+I*R

Eb=(0.75*2*3.14*600)/60=47.123 volts

v=Eb+I*R

I=(V-Eb)/R=(250-47.123)/(1.1+0.8)=106.7773 amps

output power=Eb*I=47.123*106.7773=5.0316 KWATTS