An overview of the maintenance and reliability of AC traction systems

As a result of the AC technology design assessment completed by the Association of American Railroads (AAR) in 1990, the North American freight railroads have developed a performance specification for a pilot fleet of three-phase asynchronous AC traction locomotives. A preliminary economic analysis has shown that the viability of AC traction in North America lies in the fleet reduction that the specification performance levels, when implemented, can bring. However, if fleet reliability does not increase in proportion to fleet reduction, then both projected savings and viability are reduced. A study of maintenance and reliability is performed for several key European fleets of AC traction locomotives, defined in the initial AAR design assessment. Several visits were made to these European railways to gather information and review their service experience. The resulting information is revealed, with respect to the AAR Performance Specification for AC Traction Systems. The European information centers on early failure data and current reliability targets for new equipment. The performance specification is also outlined