Using its RAILSIM technology, SYSTRA performed a comprehensive traction power system study for the Metro-North Railroad (MNR) and Connecticut Department of Transportation (CDOT). Metro-North, the second busiest commuter rail network in North America, operates the Hudson and Harlem Lines in New York State, as well as the New Haven Line and three connecting branches under a funding agreement with CDOT. As the MNR operation is forecast to expand by the year 2020, with more frequent service and longer trains, the electric traction power system will continue to require reinforcement and capital investment.

In addition to MNR train services, Amtrak uses the New Haven Line as part of its Northeast Corridor train services, including both Acela Express and Regional trains. With Amtrak 2020 train services on the New Haven Line also forecast to expand significantly from current levels, there will be additional need for reinforcement and capital investment of the traction power supply system.

As CDOT, MNR and its parent agency, the Metropolitan Transit Authority (MTA), work to address future projected ridership increases, a comprehensive analysis of the additional traction power system requirements was needed. MNR/CDOT commissioned SYSTRA Engineering, Inc (SYSTRA) to perform this important study.

SYSTRA used RAILSIM to create a detailed computer simulation model of the entire system. Since the RAILSIM Load Flow Analyzer has no limitation on the complexity or extent of rail system to be modeled, the entire 650 volt Direct Current (DC) network from Grand Central to Croton-Harmon, Southeast and Pelham has been modeled in a single integrated simulation.

Similarly, the entire 13,000 volt Alternating Current (AC) New Haven line traction power system has been simulated as a single load flow model. This includes all four high voltage supply substations, all 18 auto-transformer substations, all overhead conductors (including catenary wires, contact wires, parallel feeder wires and static wires), running rails, feeder cables, return cables, inter-track bonds and phase breaks. All trains in the system are simulated using RAILSIM, with appropriate track-specific power demands generated through train movement, signal system simulation and performance calculations. Yard load cycling, switch heaters, signal power and other traction power system loads are also reflected.

RAILSIM produces detailed load cycles for all the traction power equipment, including:

• Transformer load cycle
• Feeder load cycle
• Return cable load cycle
• Overhead conductor load cycle

Detailed outputs and summaries for all of the traction power system components are included in the RAILSIM output, plus train voltage plots (at the third rail shoe or pantograph) as the trains move through the system.

SYSTRA engineers and analysts used the output data to identify areas in the traction power system requiring reinforcement for future operations. Once these areas were identified, a number of engineering solutions were simulated to assess their effectiveness. These measures include

• Building additional high voltage supply substations
• Reconfiguring and/or upgrading auto-transformer substations

The impacts of the new M-8 vehicles on the traction power system were also assessed as part of the study. The results have been used as part of the input for vehicle procurement specification for these latest planned additions to the New Haven Line fleet.

Numerous recommendations for capital projects were made to CDOT and Metro-North as a result of the study. Inclusion of the necessary improvements and replacements in their capital programs is the single most important hallmark of success of the Traction Power System Study.