Technical Reports

Chopper Locomotive Demonstration Program Phase II, Final Report

  • 01
  • Apr
  • 1984
AUTHOR: Robert Hopkins
SUBJECT: Motive Power and Equipment
KEYWORDS: Chopper Controls, Power Factor, Electric Propulsion
ABSTRACT: An E44 electric locomotive of 5000 hp, 6 axles and 6 motors was used as a test bed to evaluate full scale use of 6 separate high power DC to DC choppers for propulsion. The normal phase control rectifier equipment was removed and replaced by a DC link at 2000 volts as the source of energy to the choppers. The choppers were then free to operate at any optimum frequency rather than being tied to the catenary frequency. Catenary power fed the link on a continuous basis thus providing a line power factor very close to unity (95%). The project was a joint venture of the Federal Railroad Administration, Conrail and The General Electric Company. The old phase controlled electronics was removed at the Erie plant of General Electric and replaced by 6 choppers with the necessary ancillary equipment. The new propulsion system was matched to the normal E44 performance. The ability to operate in multiple with other diesel locomotives was also provided. The objective of this project was to demonstrate that modem power electronics could be applied to an electric locomotive. Tests showed that all of the advantages available from this method of propulsion i.e. high efficiency, high power factor and smooth control can be achieved.