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National Railroad Passenger Corp. (Amtrak)

Acela and HHP Locomotives Traction Power Diagnostics

LTK assisted Amtrak in the design, development and commissioning of the Acela High Speed Train sets and HHP locomotives between 1993 and 2002. This project also included the North End Electrification Project, a major design and construction effort with new 25 kV, 60 Hz catenary between New Haven, CT and Boston, MA.

SI1LTK served as the lead engineering firm for this project from start to finish with tasks of specification writing, evaluation of product offerings, design reviews, vehicle testing at TTCI in Pueblo, CO and on Amtrak’s Northeast Corridor (NEC) between Washington, DC and Boston.

LTK participated in every aspect of the design including propulsion, auxiliary power, HVAC, the dynamic tilting system, friction brakes, lighting, on-board diagnostics, the nine-aspect cab signal package, the Advanced Civil Speed Enforcement System (ACSES) and communications.

LTK provided expert diagnostics of catenary voltage fluctuations, a phenomenon that occurred at Washington Union Station when the number of Acela train sets and HHPs located there reached a critical value. The catenary voltage is normally 11.5 kV, 25 Hz but because of interactions between the new vehicle control systems, an oscillation would occur. There was a 3-4 kV amplitude oscillation at 3 Hz on the catenary voltage, sometimes sustained for hours. This caused the Acela train sets and HHP locomotives to open their main circuit breakers because of inverter faults. LTK staged a number of tests at Union Station to first establish the cause of this problem and later work with the equipment supplier (ALSTOM) to solve it.

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Bay Area Rapid Transit District (BART)

System-wide Rail Wear Analysis

LTK is working under a General Engineering Consultant (GEC) assignment for the Bay Area Rapid Transit District (BART) to conduct an analysis of rail wear trends throughout the BART system as part of a rail replacement planning study.  The objective of this analysis is to provide near- and intermediate-term projections of BART’s rail replacement requirements for its 104 route-mile system.

SI2Using specialized instrumentation and field services provided by a subcontractor, LTK is performing field measurements of all mainline trackage with a hi-rail cart adapted to BART’s unique track gauge.  Laser scan equipment on the cart reads key rail measurements over the running surface and gauge every two feet.  BART-supplied equipment tows and powers the cart. 

LTK also arranged to convert BART’s historical rail wear data to the subcontractor’s viewer format; this allows side-by-side comparison of the latest data and historical data.  The image below shows a sample of the viewer output with data from three tests.  Represented in this graph is the high side of a curve with test data from 1996, 2001, and 2008.  The 1996 data shows very little wear, but the 2001 shows a worn profile with 15.8% head loss.  The 2008 data shows more modest head wear, indicating BART replaced the curve since 2001.

As part of the analysis, LTK is reviewing the current and historical data sets to develop predictions regarding when rail will wear to its condemning limit.  Current data are checked visually to confirm the nature and extent of the rail wear present. LTK then performs automated multi-variate linear regression analyses to determine the rate of railhead loss and the estimated condemnation date.

Future phases of this work will investigate means of controlling rail wear.  Potential avenues include modified rail lubrication and grinding schedules, enhanced wheel truing, and truck rebuilding.

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Hampton Roads Transit

Light Rail System

Hampton Roads Transit (HRT) LRT will operate its initial system along an east-west corridor from the East Virginia Medical Center station as the westernmost terminus to the Newtown Rd station on the east.  The right-of-way is located in both dedicated lanes of existing streets and along a dedicated right of way that follows an abandoned Norfolk/Southern railroad line.  Within the central business district, the LRT will have street intersections that will be controlled to give priority to the light rail vehicles.  The dedicated right of way portion of the system will include an automatic block system that will provide for separation of the vehicles. 

SI3LTK was asked to assist HRT during the LRV selection process and subsequently has provided assistance with the procurement and construction management of the traction power and OCS systems.  The LRVs are being manufactured by Siemens Transportation Systems at its Sacramento, CA facility.  With procurement guidance from LTK, HRT entered into an agreement with Charlotte Area Transit System (CATS) in order to be assigned a portion of the existing unused options on the CATS LRV contract with Siemens.  LTK staff supervised the quality control/quality assurance process during construction of the vehicles.  The firm supports HRT in the procurement of the vehicles, traction electrification (substations and overhead contact system), signals, and communications. 

As a member of the HRT Program Management Team, LTK provides engineering and program management services for reviewing the design of new systems and manufacturing of the state-of-the-art light rail vehicles for the new Norfolk light rail system. LTK has provided a review of the various systems and safety plans and has developed the systems integration test plan and procedures.  The line is scheduled to open in 2010.

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Minnesota Department of Transportation

Hiawatha Corridor Light Rail Project (1999-2000) (2001-2004)

LTK’s involvement with light rail transit in the Twin Cities extends back to 1985. The firm assisted in developing LRT systems plans for the Twin Cities by conducting a series of studies that defined “starter lines” in individual corridors. Several routes were identified as having good potential for LRT, including a corridor in Hennepin County radiating from downtown Minneapolis and one penetrating the core of St Paul. As part of developing a comprehensive LRT plan for the County, LTK completed tasks involving operational analyses and systems engineering. The firm was responsible for a feasibility analysis of LRV options including low-floor LRVs, car lengths, maximum train lengths and vehicle operating parameters.  LTK staff developed design criteria, which became the blue print for the PE and final design.

SI4Separate contracts with the Minnesota Department of Transportation as well as Hennepin and Ramsey counties, covered all systems elements, including LRVs, LRT signal system, traction electrification, communications and central control, system wide electrical, fare collection, yard and shop design, and maintenance support equipment during preliminary engineering for both the Hiawatha and Central Corridors.  LTK developed operating and maintenance plans, performed corrosion control analyses and prepared cost estimates for all elements.

LTK assisted in the preparation of Design Build contract documents for the design, implementation and construction of the Hiawatha LRT Corridor, a 12.5-mile line using a combination of street operation, exclusive ROW operation and tunnel operation.  LTK was responsible for all systems elements including systems integration, signals, communications, central control, TWC, traction substations, overhead contact system, system wide electrical, yard and shop facilities and maintenance equipment.  The firm also was responsible for two major elements outside the Design Build contract, the procurement of 34 low-floor light rail vehicles and the planning and implementing of a comprehensive regional fare collection plan including LRT, bus and commuter rail. Associated with this project, but under contract to the Metropolitan Airports Commission, LTK supported the detailed design of tunnel electrical/transit facilities and provided detailed corrosion control design assistance.

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NJ Transit

ALP-46 Locomotive EMI/EMC Diagnostics

LTK was selected by NJ TRANSIT to oversee all ALP-46 locomotive vehicle level Electro-magnetic Interference (EMI) testing at TTCI, Pueblo, CO in 2002. The ALP-46 is an electric locomotive built by Bombardier in Germany. The Conducted, Induced and Radiated testing was completed with no exceptions. However when the Cab Signal Interference (CSI) was measured at about 5 amps by the cab signal system supplier, LTK was tasked with resolving this problem. LTK was selected, in part, because of its extensive past experience with CSI on AC powered locomotives.

SI5LTK engineers recommended the relocation of the track receiver coils farther forward and away from the lead traction motor. In addition, LTK recommended that the cables to the lead traction motor be rerouted and grouped closer together in a triangle configuration.  A retest at TTCI confirmed the CSI was reduced from 5 amps to about 1 amp but this fell short of 0.3 amp. Maximum tolerable CSI current 

LTK engineers then experimented with a shield between the traction motor and the track receiver coils. The shield was installed on the ALP-46 and CSI was further reduced to about 0.5 amps. LTK continued to work with Bombardier to refine a shield design for this locomotive. This effort was successful and the CSI was reduced to the 0.3 amp limit. LTK engineers also considered reducing the traction motor flux, but this was found to be unnecessary given the successful 0.3 amp current limit.

When the prototype locomotive arrived in New Jersey, LTK took part in a repeat of the EMI tests on the NJ TRANSIT system. LTK also investigated several Electro-magnetic Compatibility (EMC) issues being experienced by NJT with the ALP-46 operation. In one case, the brakes would release when the Main Circuit Breaker (MCB) closed. LTK investigated the wiring to the traction motor speed sensors and recommended rewiring to resolve this issue.

Another problem occurred with the Line Monitor Electronics which would reset when the MCB closed. This unit is quite sensitive and was mounted in close proximity to the MCB; LTK engineers recommended the installation of a small plate and this shielding resolved the problem.

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New York City Transit (NYCT)

Procurement of New Rapid Transit Cars

In 1996, NYCT began a major procurement of new cars for service on its famed subway system, one of the largest in the world. The first of the new cars were designated R142 and R142A for use on the ‘A’ Division (formerly the IRT); the second and third series of cars were designated R143 and R160 and were for use on the ‘B’ Division (formerly the BMT and IND). LTK has played an integral role in the procurement of all of these new fleets.

SI6LTK’s design and procurement process duties for the R142 and R142A programs included developing the car technical specifications and commercial terms; assisting in developing the contractor selection process; participating in selection activities and contract negotiations. These two concurrently-designed cars are operationally compatible and perceived by the passenger as identical in service. Similarly, LTK assisted NYCT throughout the design and procurement process for the R143 program.

For the R142, R142A and R143 car procurements, LTK provided program management assistance; program controls assistance; design review of contractor submittals; first article inspection (engineering portion); qualification test witnessing (component, system, car, unit); commissioning and warranty period technical support; system integration and production oversight (QA/QC).

For the R160 car procurement, LTK staff members assisted with the development of the technical specifications and commercial terms, and participated in the contractor selection process. LTK continues to support the R160 program with a full complement of technical and program management skills to oversee the design, production and deployment of the rail vehicles.

LTK is currently assisting NYCT with the procurement of some additional R142 and R142A cars that will be equipped with CBTC equipment.

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