Electrical Power Systems Technology

Direct Current Power Systems 169

Construction of DC Generators

The parts of a simple DC generator are shown in Figure 7-9. prin-The

ciple of operation of a DC generator is similar to that of the AC generator,

which was discussed previously. A rotating armature coil passes through a

magnetic field that develops between the north and south polarities of per-

manent magnets or electromagnets. As the coil rotates, electromagnetic in-

duction causes a current to be induced into the coil. The current produced

Figure 7-8. Sealed nickel-cadmium rechargeable cylindrical type cell-exploded

view (Courtesy Eveready Corp.)