The General Motors GF6C Electric Locomotive

Following a favorable analysis for electric versus diesel-electric locomotives, British Columbia Railway awarded a contract for seven electric locomotives to the Diesel Division of General Motors of Canada, in August 1982. The development and design effort was coordinated between ASEA of Sweden, the Electro-Motive Division of General Motors in La Grange, IL, and Diesel Division. This phase of the project, along with the manufacture and production of the locomotives and the testing of the units, was completed in a record 14 months. The first unit was shipped in November 1983. The GF6C is rated at 3800 kW and operates on a 50-kV ac single-phase catenary. It is a six-axle unit, with a total weight of 392 200 lb. It is powered by six separately excited dc traction motors. Following a brief description of the mechanical systems and their design considerations, details of the electrical components and systems are provided. A description of the various equipment, including that mounted on roof and underframe, is provided. The design considerations are also highlighted. A basic block diagram description of the control circuits is given. Two thyristor motor modules are employed, each consisting of two thyristor-diode bridges connected in series. The module controls the armatures of three traction motors, and the field of each motor is controlled individually by thyristors. A description of the creep control system and the overall control system is provided. Finally, the test and performance results of the locomotive are highlighted.