Electrical Power Systems Technology

Direct Current Power Systems 177

will increase the I × R drop in the armature, resulting in a smaller output

voltage. Further increases in load current cause corresponding decreases

in output voltage, as shown in the output curve of Figure 7-16. With small

load currents, the output voltage remains nearly constant as load current

Figure 7-15. Simplified illustration of a self-excited, shunt-wound DC generator:

(A) Pictorial diagram, (B) Schematic diagram

Figure 7-16. Output curve of a shunt-wound DC generator