DIESEL ELECTRIC LOCOMOTIVETRACTION ALTERNATOR

The Traction Alternator is a three phase AC alternator consisting of a ten-field pole rotor, a set of slip rings to conduct excitation current to the rotor windings and two sets of stator windings. The two sets of stator windings (which are stationary and mounted to the inside of the alternator yoke or frame) create two separate sources of 3-phase AC power. The output from the stators depends on the speed at which the engine is turning the rotor, and the strength of the rotating magnetic field. The action of the magnetic field or “lines of force” passing through the stator windings produces the alternator's output. The engine rpm for each throttle position establishes the rpm of the rotor, since it is directly coupled to the engine. The control of the magnetic field strength is done through the Traction Alternator field supply chopper, which is in turn, controlled by the locomotive's computer system based on feedback information.
Companion Alternator CA6

• A Rotor with 16 field poles.

• Slip rings (1 and 2) and brushes to conduct excitation current to the rotor field windings.

• The two slip rings (1 and 2) and four corresponding brushes conduct excitation current to the rotating field of the companion alternator.

• Two isolated stator windings in a common stator housing which produces three different three-phase AC outputs.