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{{Short description|Northeast Corridor railroad power system}}
[[File:Amt930-bostonMA.jpg|thumb|300px|An [[AEM-7]] electric locomotive brings an Amtrak train into [[South Station]], Boston, in 2001]]
[[File:Amt930-bostonMA.jpg|thumb|An [[AEM-7]] electric locomotive brings an Amtrak train into [[South Station]], Boston, in 2001]]
⚫
[[Amtrak]] operates a '''60&nbsp;Hz Traction power system''' along the [[Northeast Corridor]] between [[New Haven, Connecticut]]<ref>Specifically, Amtrak's 25 kV system begins at the Mill River Interlocking about two miles north of New Haven Station {{Coord|41.311281|-72.911775|name=Mill River Interlocking (Southern End of Amtrak 25 kV Electrification)}}</ref> and [[Boston, Massachusetts]]. This system was built in the late 1990s and supplies locomotives with power from an [[overhead lines|overhead catenary system]] at 25&nbsp;kV, 60&nbsp;Hz. The system is also commonly known as the ''Northend Electrification'', in contrast to the ''Southend Electrification'' that runs from New York City to Washington DC.

⚫
'''Amtrak’s 60&nbsp;Hz traction power system''' operates along the [[Northeast Corridor]] between [[New Haven, Connecticut]],<ref group=note>Specifically, Amtrak's 25 kV system begins at the Mill River Interlocking about two miles north of New Haven Union Station {{Coord|41.311281|-72.911775|name=Mill River Interlocking (Southern End of Amtrak 25 kV Electrification)}}</ref> and [[Boston, Massachusetts]]. This system was built by [[Amtrak]] in the late 1990s and supplies locomotives with power from an [[overhead lines|overhead catenary system]] at 25&nbsp;kV alternating current with at 60&nbsp;Hz, the standard frequency in North America. The system is also known as the '''Northend Electrification''', in contrast to [[Amtrak's 25 Hz traction power system]] that runs between New York City and Washington, D.C., which is known as the Southend Electrification system.


==History==
==History==
⚫
In 1992, Congress passed the ''Amtrak Authorization and Development Act'' requiring Amtrak to establish high-speed rail passenger service between New York City and Boston. The goal was to reduce travel time in this corridor from 4.5 hours to less than 3 hours. Revenue from this service was expected to play a critical role in helping Amtrak achieve operating self-sufficiency by 2003. Before Amtrak could begin high-speed rail service, {{convert|155|miles}} of rail line between New Haven and Boston had to be electrified. Previously, electrified [[Metroliner (Amtrak)|Metroliner]] service was available between Washington, D.C., and New Haven, Connecticut. At New Haven, Amtrak had to switch to a diesel locomotive to complete the trip to Boston. In addition to the higher operating speeds possible with electrified service, Amtrak also saves the time it spent on switching locomotives. By the time the project was complete, Amtrak was expected to have spent over $600 million to electrify the line between New Haven and Boston.<ref name="FRAreport">{{cite web| url=https://www.oig.dot.gov/sites/default/files/rt2000020.pdf| title=Report on Amtrak's High-Speed Rail Electrification Project| author=Federal Railroad Administration Inspector General| date=December 14, 1999| access-date=September 28, 2017}} Report No: RT-2000-020</ref> Including extensive track and infrastructure improvements besides the electrification, the project cost $1.6 billion.<ref>{{cite news| url=https://www.nytimes.com/1999/03/10/nyregion/amtrak-unveils-its-bullet-to-boston.html| title=Amtrak Unveils Its Bullet to Boston| first=Thomas J.| last=Lueck| date=March 10, 1999| website=New York Times}}</ref>


⚫
In December 1995, Amtrak awarded a $321 million contract to [[Balfour Beatty Construction]], Inc./Mass. Electric Construction (BBC/MEC) to verify and complete the [[Morrison-Knudsen]] design and build the electrification system. The system was to be completed by June 1999; electrification system ground-breaking ceremony took place the following July.
⚫
In 1992, Congress passed the ''Amtrak Authorization and Development Act'' requiring Amtrak to establish high-speed rail passenger service between New York City and Boston. The goal was to reduce travel time in this corridor from 4.5 hours to less than 3 hours. Revenue from this service was expected to play a critical role in helping Amtrak achieve operating self-sufficiency by 2003. Before Amtrak could begin high-speed rail service, 155 miles of rail line between New Haven and Boston had to be electrified. Previously, electrified [[Metroliner (Amtrak)|Metroliner]] service was available between Washington, D.C. and New Haven, Connecticut. At New Haven, Amtrak had to switch to a diesel locomotive to complete the trip to Boston. In addition to the higher operating speeds possible with electrified service, Amtrak also saves the time it spent on switching locomotives. By the time the project was complete, Amtrak was expected to have spent over $600 million to electrify the line between New Haven and Boston.<ref name=FRAreport>[https://www.oig.dot.gov/sites/default/files/rt2000020.pdf Report on Amtrak’s High-Speed Rail Electrification Project] Federal Railroad Administration Inspector General Report No: RT-2000-020, December 14, 1999, accessed September 28, 2017</ref> Including extensive track and infrastructure improvements besides the electrification, the project cost $1.6 billion.<ref>https://www.nytimes.com/1999/03/10/nyregion/amtrak-unveils-its-bullet-to-boston.html</ref>


⚫
[[File:South Bay Interchange.jpg|thumb|Approach to [[South Station]], Boston, showing electrified track (left) and the massive complex of roads that were under construction at the same time as the electrification.]]
⚫
In December 1995, Amtrak awarded a $321 million contract to [[Balfour Beatty Construction]], Inc./Mass. Electric Construction (BBC/MEC) to verify and complete the [[Morrison-Knudsen]] design and build the electrification system. System was to be completed by June 1999. Electrification system ground-breaking ceremony took place the following July.


⚫
[[File:South Bay Interchange.jpg|thumb|300px|Approach to [[South Station]], Boston, showing electrified track (left) and the massive complex of roads that were under construction at the same time as the electrification.]]
Amtrak's contractor faced a difficult working environment in the [[South Station|Boston Terminal Area]] because of the extensive work being undertaken for the [[Central Artery project]], which involved over 500 employees in the South Boston Terminal area alone and entailed on-site storage of a large amount of heavy construction equipment and supplies. The Central Artery project was ongoing before the electrification project started. Another factor complicating electrification work in the Boston Terminal Area is the large volume of rail traffic. Over 250 [[Massachusetts Bay Transportation Authority]] (MBTA) commuter trains and 20 Amtrak trains operate through the area daily. As a result, taking track out of service to work on the electrification was sometimes difficult.
Amtrak's contractor faced a difficult working environment in the [[South Station|Boston Terminal Area]] because of the extensive work being undertaken for the [[Central Artery project]], which involved over 500 employees in the South Boston Terminal area alone and entailed on-site storage of a large amount of heavy construction equipment and supplies. The Central Artery project was ongoing before the electrification project started. Another factor complicating electrification work in the Boston Terminal Area is the large volume of rail traffic. Over 250 [[Massachusetts Bay Transportation Authority]] (MBTA) commuter trains and 20 Amtrak trains operate through the area daily. As a result, taking track out of service to work on the electrification was sometimes difficult.


Electrification work on the five [[movable bridge]]s between [[Old Saybrook (Amtrak station)|Old Saybrook]] and [[Mystic (Amtrak station)|Mystic]] in Connecticut was also a challenge, as each one required a unique electrification design and construction solution. The bridges span busy waterways shared by pleasure craft, commercial carriers, and military traffic. Unlike most movable highway bridges, these bridges are usually open, and are closed only to accommodate approaching train traffic.<ref name=FRAreport />
Electrification work on the five [[movable bridge]]s between [[Old Saybrook (Amtrak station)|Old Saybrook]] and [[Mystic (Amtrak station)|Mystic]] in Connecticut was also a challenge, as each one required a unique electrification design and construction solution. The bridges span busy waterways shared by pleasure craft, commercial carriers, and military traffic. Unlike most movable highway bridges, these bridges are usually open, and are closed only to accommodate approaching train traffic.<ref name="FRAreport" />


After several delays, service with electric locomotives between New Haven and Boston began on January 31, 2000.<ref>{{cite journal | last=Middleton | first=William D. | authorlink=William D. Middleton | title=Super Railroad | journal=[[Trains (magazine)|Trains]] | volume=63 | issue=3 | pages=36–59 | date=March 2003 | issn=0041-0934}}</ref> Amtrak began operating its higher-speed [[Acela Express]] service on December 11, 2000.<ref>[http://articles.latimes.com/2000/dec/13/news/mn-64918 Amtrak’s new Hit-Speed Service is Derailed by Mechanical Problem], ''LA Times''/AP, December 13, 2000</ref>
After several delays, service with electric locomotives between New Haven and Boston began on January 31, 2000.<ref>{{cite journal| last=Middleton| first=William D.| author-link=William D. Middleton| title=Super Railroad| journal=[[Trains (magazine)|Trains]]| volume=63| issue=3| pages=36–59| date=March 2003| issn=0041-0934}}</ref> Amtrak began operating its higher-speed [[Acela Express]] service on December 11, 2000.<ref>{{cite news| url=https://www.latimes.com/archives/la-xpm-2000-dec-13-mn-64918-story.html| title=Amtrak's new Hit-Speed Service is Derailed by Mechanical Problem| website=Los Angeles Times| agency=Associated Press| date=December 13, 2000}}</ref>


== Types of stations ==
== Types of stations ==
=== System architecture ===
=== System architecture ===
[[File:A catenary pole with balancing weights on Amtrak's NEC.jpg|thumb|upright|A catenary pole of the system. Catenary wires and contact wires are tensioned by individual tension balancers.]]
⚫
The basic system unit is an '''Elementary Electrical Section''' consisting of a segment of one or more parallel tracks, each with a contiguous contact (or catenary or trolley) wire for the locomotive pantograph and an electrically separate feed wire. Elementary electrical sections are separated by [[Overhead lines#Section Break|section breaks]] where the contact and feeder wires can be interrupted with motor-operated air switches to isolate a section in the event of a fault or to permit maintenance.


⚫
The basic system unit is an ''elementary electrical section'' consisting of a segment of one or more parallel tracks, each with a contiguous contact (or catenary or trolley) wire for the locomotive pantograph and an electrically separate feed wire. Elementary electrical sections are separated by [[Overhead lines#Section break|section breaks]] where the contact and feeder wires can be interrupted with motor-operated air switches to isolate a section in the event of a fault or to permit maintenance.
⚫
An '''Electrical Section''' is a collection of elementary electrical sections, section breaks, air switches and paralleling stations between a '''Substation''' and a '''Switching Station'''.


⚫
An ''electrical section'' is a collection of elementary electrical sections, section breaks, air switches and paralleling stations between a ''substation'' and a ''switching station''.
At each substation, utility supplied single phase power is transformed and injected into the two electrical sections terminating at that substation. There are eight electrical sections in the system, two for each substation. The substations drive the contact and feed wires in a [[split phase]] arrangement so that each wire is at 25&nbsp;kV with respect to the grounded running rails with 50&nbsp;kV between them.


At periodically spaced '''Paralleling Stations''' within each electrical section the tracks' catenary wires are connected together to one side of an [[autotransformer]] and the feeder wires are connected together to the other side of the autotransformer. The autotransformer center-tap is connected to the grounded running rails that return the current from the locomotives. The paralleling stations thus reduce voltage drops by feeding a locomotive from both directions along its contact wire and spreading the load across all the contact and feed wires of a multitrack system. The split-phase arrangement also gains the increased efficiency of operating at 50&nbsp;kV while the highest voltage with respect to ground remains only 25&nbsp;kV. (The same split-phase method is used in North American homes to supply high power loads such as air conditioners with the efficiency of a 240&nbsp;V supply while retaining the safety advantages of a 120&nbsp;V supply.)
At each substation, utility-supplied single phase power is transformed and injected into the two electrical sections terminating at that substation. There are eight electrical sections in the system, two for each substation. The substations drive the contact and feed wires in a [[split phase]] arrangement so that each wire is at 25&nbsp;kV with respect to the grounded running rails with 50&nbsp;kV between them.
At periodically spaced ''paralleling stations'' within each electrical section the tracks' catenary wires are connected together to one side of an [[autotransformer]] and the feeder wires are connected together to the other side of the autotransformer. The autotransformer center tap is connected to the grounded running rails that return the current from the locomotives. The paralleling stations thus reduce voltage drops by feeding a locomotive from both directions along its contact wire and spreading the load across all the contact and feed wires of a multitrack system. The split-phase arrangement also gains the increased efficiency of operating at 50&nbsp;kV while the highest voltage with respect to ground remains only 25&nbsp;kV. (The same split-phase method is used in North American homes to supply high power loads such as air conditioners with the efficiency of a 240&nbsp;V supply while retaining the safety advantages of a 120&nbsp;V supply.)


=== Substations ===
=== Substations ===
[[File:BranfordSS.png|thumb|Branford Substation]]
<!-- Deleted image removed: [[File:BranfordSS.png|thumb|Branford Substation]] -->
There are four '''Substations''' between New Haven and Boston:
There are four ''substations'' between New Haven and Boston:
* Branford, CT
* Branford, CT
* New London, CT
* New London, CT
* Warwick, RI
* Warwick, RI
* Sharon, MA
* Sharon, MA
Each station contains two 115 kV (single phase) to 50 kV (single phase with center tap) transformers to convert the utility supplied transmission voltage to 50kV traction voltage. Output circuit breakers, and a capacitor based filter network are installed. The filter banks suppress the high frequency (that is anything above 60&nbsp;Hz) harmonics on the catenary lines generated by locomotives' solid-state traction motor inverters. The filters also provide reactive power support and correct for power factor. Amtrak's 60&nbsp;Hz electrification distributes power using ±25 kV from ground via a center tap of the 115/50 kV transformers. This system is also known as ''2 x 25 kV''.
Each station contains two 115 kV (single phase) to 50 kV (single phase with center tap) transformers to convert the utility supplied transmission voltage to 50&nbsp;kV traction voltage. Output circuit breakers, and a capacitor based filter network are installed. The filter banks suppress the high frequency (that is anything above 60&nbsp;Hz) harmonics on the catenary lines generated by locomotives' solid-state traction motor inverters. The filters also provide reactive power support and correct for power factor. Amtrak's 60&nbsp;Hz electrification distributes power using ±25 kV from ground via a center tap of the 115/50 kV transformers. This system is also known as ''2 × 25 kV''.


=== Switching stations ===
=== Switching stations ===
Three '''Switching Stations''' are located along the line which separate the different electrical sections (power zones):
Three ''switching stations'' are the equivalent of distribution level substations, which transform higher voltage electricity to the 25&nbsp;kV voltage, and are located along the line which separate the different electrical sections (power zones):
* Westbrook, CT
* Westbrook, CT
* Richmond, RI
* Richmond, RI
Line 41: Line 45:
The switching stations contain three [[autotransformer]]s similar to the paralleling stations (which have one), and also have additional circuit breakers to allow segmentation of catenary and cross-connection between power zones.
The switching stations contain three [[autotransformer]]s similar to the paralleling stations (which have one), and also have additional circuit breakers to allow segmentation of catenary and cross-connection between power zones.


Electrical sections encompass both tracks between a substation and the adjacent switching stations. Normally no power flows from one side of a switching station to the other side; it is like two adjacent paralleling stations which serve different electrical sections. In the event that a substation is taken out of service, switching stations have additional circuit breakers which allow feeding an electrical section from the adjacent section.
Electrical sections encompass both tracks between a substation and the adjacent switching stations. Normally no power flows from one side of a switching station to the other side; it is like two adjacent paralleling stations which serve different electrical sections. In the event that a substation is taken out of service, switching stations have additional circuit breakers which allow feeding an electrical section from the adjacent section.


Since switching stations, like substations, normally separate electrical sections with different supply sources (and thus different phase or voltage), a neutral section<ref>The terms [[Overhead lines#Phase Break|Phase Break]], neutral section, and [[Overhead lines#Dead Section|Dead Section]], are colloquially interchanged. Agarwal refers to these as 'neutral sections'. In the ex-PRR portions of Amtrak's system, they would be known as Dead Sections.</ref> always occupies the track between the two electrical sections.
Since switching stations, like substations, normally separate electrical sections with different supply sources (and thus different phase or voltage), a neutral section{{refn|group=note|The terms 'phase break', '[[Overhead lines#Neutral section (phase break)|neutral section]]', and '[[Overhead lines#Dead section|dead section]]' are colloquially interchanged. Agarwal refers to these as 'neutral sections'.<ref>{{cite conference |last=Agarwal |first=K.K. |title=ASME/IEEE Joint Railroad Conference |chapter=Automatic fault location and isolation system for the electric traction overhead lines |conference=2002 ASME/IEEE Joint Railroad Conference |date=2002 |pages=117–122 |doi=10.1109/RRCON.2002.1000103|isbn=0-7803-7452-5 }}.
</ref> In the ex-PRR portions of Amtrak's system, they would be known as 'dead sections'.}} always occupies the track between the two electrical sections.


In the event of a fault in one elementary electrical section, the switching station can 'back-feed' the far portion of the affected track from the non-affected track, which the supplying substation feeds the near end.
In the event of a fault in one elementary electrical section, the switching station can 'back-feed' the far portion of the affected track from the non-affected track, which the supplying substation feeds the near end.
Line 50: Line 55:
[[File:StoningtonPS.png|thumb|Stonington Paralleling Station]]
[[File:StoningtonPS.png|thumb|Stonington Paralleling Station]]
[[File:NoankPS.png|thumb|Noank Paralleling Station]]
[[File:NoankPS.png|thumb|Noank Paralleling Station]]
Eighteen '''Paralleling Stations''' are located at approximately six mile intervals<ref>EMF, p. 5</ref> along the line. Each contains a single autotransformer (with the exception of Roxbury, which has two), automatic circuit breakers, motor-operated air switches, and a control shed. The autotransformers are rated at 10 MVA, 1.2% impedance, two winding, 27.5 kV.<ref>Natarajan, 453.</ref>
Eighteen ''paralleling stations'' are located at approximately six mile intervals{{sfn|EMF|p=5}} along the line. Each contains a single autotransformer (with the exception of Roxbury, which has two), automatic circuit breakers, motor-operated air switches, and a control shed. The autotransformers are rated at 10 MVA, 1.2% impedance, two winding, 27.5 kV.{{sfn|Natarajan|Imece|Popoff|Agarwal|1999|p=453}}


Each paralleling station bus is connected to both north and south track catenary and feeder lines via automatic circuit breakers. The autotransformer is connected to the bus bars by an additional circuit breaker. The track breakers at the paralleling stations trip on sensing no-voltage. Thus when a line fault causes the supplying substation breakers to trip, the paralleling stations also trip. This action separates the two tracks from one another electrically and allows the substation to automatically restore one of the tracks (the non-faulted one). After a variable time delay (to reduce simultaneous inrush current), over-voltage relays will re-shut the track circuit breakers on the non-faulted track.
Each paralleling station bus is connected to both north and south track catenary and feeder lines via automatic circuit breakers. The autotransformer is connected to the bus bars by an additional circuit breaker. The track breakers at the paralleling stations trip on sensing no-voltage. Thus when a line fault causes the supplying substation breakers to trip, the paralleling stations also trip. This action separates the two tracks from one another electrically and allows the substation to automatically restore one of the tracks (the non-faulted one). After a variable time delay (to reduce simultaneous inrush current), over-voltage relays will re-shut the track circuit breakers on the non-faulted track.


== List of stations ==
== List of stations ==
[[File:SubstationSchematicNorthend.png|thumb|Schematic of Substations along the Northend Electrification]]
[[File:SubstationSchematicNorthend.png|thumb|Schematic of substations along the Northend Electrification]]
{{GeoGroupTemplate}}
{{GeoGroupTemplate}}


{| class="wikitable sortable" border="1" cellpadding="4" cellspacing="0"
{| class="wikitable sortable"
|+ Amtrak Northend Electrification Stations
|+ Amtrak Northend Electrification Stations
! style="width:8%" | MP<ref>Natarajan, p. 451</ref>
! style="width:8%" | MP{{sfn|Natarajan|Imece|Popoff|Agarwal|1999|p=451}}
! style="width:8%" | State
! style="width:8%" | State
! style="width:16%" | Municipality
! style="width:16%" | Municipality
! style="width:16%" | Type
! style="width:16%" | Type
! style="width:22%" | Coordinates
! style="width:22%" | Coordinates
! style="width:38%" | Comments
! style="width:38%" | Comments
|-
|-
| 228.49 || MA || [[South Station|Boston (South)]] || N/A || || End of Electrification
| 228.49 || MA || Boston ([[South Station]]) || N/A || || End of electrification
|-
|-
| 226.12 || MA ||Roxbury || Paralleling Station || {{Coord|42.3331|-71.0937|name=Roxbury Paralleling Station}} ||
| 226.12 || MA || Roxbury || Paralleling station || {{Coord|42.3331|-71.0937|name=Roxbury paralleling station}} ||
|-
|-
| 219.08 || MA || Readville || Paralleling Station || {{Coord|42.2365|-71.1343|name=Readville Paralleling Station}} ||
| 219.08 || MA || Readville || Paralleling station || {{Coord|42.2365|-71.1343|name=Readville paralleling station}} ||
|-
|-
| 212.36 || MA || Sharon || Substation || {{Coord|42.1442|-71.1642|name=Sharon Substation}} ||
| 212.36 || MA || Sharon || Substation || {{Coord|42.1442|-71.1642|name=Sharon substation}} ||
|-
|-
| 204.98 || MA || East Foxboro || Paralleling Station || {{Coord|42.0456|-71.2107|name=East Foxboro Paralleling Station}} ||
| 204.98 || MA || East Foxboro || Paralleling station || {{Coord|42.0456|-71.2107|name=East Foxboro paralleling station}} ||
|-
|-
| 198.68 || MA || Norton || Switching Station || {{Coord|41.969|-71.2652|name=Norton Switching Station}} ||
| 198.68 || MA || Norton || Switching station || {{Coord|41.969|-71.2652|name=Norton switching station}} ||
|-
|-
| 193.41 || MA || Attleboro || Paralleling Station || {{Coord|41.903555|-71.322914|name=Attleboro Paralleling Station}} ||
| 193.41 || MA || Attleboro || Paralleling station || {{Coord|41.903555|-71.322914|name=Attleboro paralleling station}} ||
|-
|-
| 187.60 || RI || Providence || Paralleling Station || {{Coord|41.860604|-71.406251|name=Providence Paralleling Station}} ||
| 187.60 || RI || Providence || Paralleling station || {{Coord|41.860604|-71.406251|name=Providence paralleling station}} ||
|-
|-
| 181.89 || RI || Elmwood || Paralleling Station || {{Coord|41.798065|-71.42868|name=Elmwood Paralleling Station}} ||
| 181.89 || RI || Elmwood || Paralleling station || {{Coord|41.798065|-71.42868|name=Elmwood paralleling station}} ||
|-
|-
| 176.94 || RI || Warwick || Substation || {{Coord|41.732459|-71.440597|name=Warwick Substation}} ||
| 176.94 || RI || Warwick || Substation || {{Coord|41.732459|-71.440597|name=Warwick substation}} ||
|-
|-
| 169.82 || RI || East Greenwich || Paralleling Station || {{Coord|41.634505|-71.463999|name=East Greenwich Paralleling Station}} ||
| 169.82 || RI || East Greenwich || Paralleling station || {{Coord|41.634505|-71.463999|name=East Greenwich paralleling station}} ||
|-
|-
| 161.81 || RI || Exeter || Paralleling Station || {{Coord|41.525942|-71.518782|name=Exeter Paralleling Station}} ||
| 161.81 || RI || Exeter || Paralleling station || {{Coord|41.525942|-71.518782|name=Exeter paralleling station}} ||
|-
|-
| 157.15 || RI || Kingston || Paralleling Station || {{Coord|41.475541|-71.57462|name=Kingston Paralleling Station}} ||
| 157.15 || RI || Kingston || Paralleling station || {{Coord|41.475541|-71.57462|name=Kingston paralleling station}} ||
|-
|-
| 150.15 || RI ||Richmond || Switching Station || {{Coord|41.437637|-71.689892|name=Richmond Switching Station}} ||
| 150.15 || RI ||Richmond || Switching station || {{Coord|41.437637|-71.689892|name=Richmond switching station}} ||
|-
|-
| 145.19 || RI || Bradford || Paralleling Station || {{Coord|41.394712|-71.760969|name=Bradford Paralleling Station}} ||
| 145.19 || RI || Bradford || Paralleling station || {{Coord|41.394712|-71.760969|name=Bradford paralleling station}} ||
|-
|-
| 139.97 || CT || State Line || Paralleling Station || {{Coord|41.3644|-71.8403|name=State Line Paralleling Station}} ||
| 139.97 || CT || State Line || Paralleling station || {{Coord|41.3644|-71.8403|name=State Line paralleling station}} ||
|-
|-
| 134.70 || CT || Stonington || Paralleling Station || {{Coord|41.3403|-71.9254|name=Stonington Paralleling Station}} ||
| 134.70 || CT || Stonington || Paralleling station || {{Coord|41.3403|-71.9254|name=Stonington paralleling station}} ||
|-
|-
| 129.50 || CT || Noank || Paralleling Station || {{Coord|41.3234|-71.9984|name=Noank Paralleling Station}} ||
| 129.50 || CT || Noank || Paralleling station || {{Coord|41.3234|-71.9984|name=Noank paralleling station}} ||
|-
|-
| 123.56 || CT || New London || Substation || {{Coord|41.3629|-72.093|name=New London Substation}} ||Transformers are grade separated from roadbed; catenary feeders run underground.
| 123.56 || CT || New London || Substation || {{Coord|41.3629|-72.093|name=New London substation}} ||Transformers are grade separated from roadbed; catenary feeders run underground.
|-
|-
| 117.54 || CT || Millstone || Paralleling Station || {{Coord|41.3164|-72.1644|name=Millstone Paralleling Station}} ||
| 117.54 || CT || Millstone || Paralleling station || {{Coord|41.3164|-72.1644|name=Millstone paralleling station}} ||
|-
|-
| 109.30 || CT || Old Lyme || Paralleling Station || {{Coord|41.2966|-72.3044|name=Old Lyme Paralleling Station}} ||
| 109.30 || CT || Old Lyme || Paralleling station || {{Coord|41.2966|-72.3044|name=Old Lyme paralleling station}} ||
|-
|-
| 103.10 || CT || Westbrook || Switching Station || {{Coord|41.2900|-72.4112|name=Westbrook Switching Station}} ||
| 103.10 || CT || Westbrook || Switching station || {{Coord|41.2900|-72.4112|name=Westbrook switching station}} ||
|-
|-
| 98.87 || CT || Grove Beach || Paralleling Station || {{Coord|41.2768|-72.4875|name=Grove Beach Paralleling Station}} ||
| 98.87 || CT || Grove Beach || Paralleling station || {{Coord|41.2768|-72.4875|name=Grove Beach paralleling station}} ||
|-
|-
| 92.19 || CT || Madison || Paralleling Station || {{Coord|41.2840|-72.6112|name=Madison Paralleling Station}} ||
| 92.19 || CT || Madison || Paralleling station || {{Coord|41.2840|-72.6112|name=Madison paralleling station}} ||
|-
|-
| 86.10 || CT || Leetes Island || Paralleling Station || {{Coord|41.2655|-72.7250|name=Leetes Island Paralleling Station}} ||
| 86.10 || CT || Leetes Island || Paralleling station || {{Coord|41.2655|-72.7250|name=Leetes Island paralleling station}} ||
|-
|-
| 78.96 || CT || Branford || Substation || {{Coord|41.2841|-72.8537|name=Branford Substation}} || Transformers located N. of I-95.
| 78.96 || CT || Branford || Substation || {{Coord|41.2841|-72.8537|name=Branford substation}} || Transformers located N. of I-95.
|-
|-
| 73.6 || CT || Mill River Interlocking || N/A || {{Coord|41.311281|-72.911775|name=Mill River Interlocking (Southern End of Amtrak 25 kV Electrification)}} || End of 25 kV, 60&nbsp;Hz System
| 73.6 || CT || Mill River Interlocking || N/A || {{Coord|41.311281|-72.911775|name=Mill River Interlocking (southern end of Amtrak 25 kV electrification)}} || End of 25 kV, 60&nbsp;Hz system
|}
|}


== See also ==
== See also ==
* [[25 kV AC railway electrification]]
* [[25 kV AC railway electrification]]
* [[Amtrak's 25 Hz Traction Power System]] operates along the southern portions of the Northeast Corridor
* [[Amtrak's 25 Hz Traction Power System]] operates along the southern portions of the Northeast Corridor from New York to Washington
* [[Electrification of the New York, New Haven, and Hartford Railroad]], from New York to New Haven.
⚫
* [[SEPTA's 25 Hz Traction Power System]]
* [[List of current systems for electric rail traction]]
* [[List of railway electrification systems]]
* [[Overhead lines]]
* [[North–South Rail Link]]
* [[North–South Rail Link]]
⚫
* [[SEPTA's 25 Hz Traction Power System]]

⚫
== Notes ==
⚫
{{reflist| group=note}}


== References ==
== References ==
{{Reflist}}
⚫
===Notes===
⚫
{{reflist}}


===Further reading===
=== Works cited ===
⚫
* {{cite book| last1=Natarajan| first1=R.| last2=Imece| first2=A.F.| last3=Popoff| first3=J.| last4=Agarwal| first4=K.| last5=Meliopoulos| first5=S.| title=199 IEEE Power Engineering Society Summer Meeting. Conference Proceedings (Cat. No.99CH36364)| chapter=Approach to the analysis of Amtrak's systemwide grounding of the Northend Electrification Project| journal=Power Engineering Society Summer Meeting, 1999| year=1999| volume=1| pages=451–456| doi=10.1109/PESS.1999.784390| isbn=0-7803-5569-5| s2cid=109580468}} {{doi|10.1109/PESS.1999.784390}}.
⚫
*Environmental Impact Statement: [https://books.google.com/books?id=CJ02AQAAMAAJ Volume 1], [https://books.google.com/books?id=0rY2AQAAMAAJ Volume 2], [https://books.google.com/books?id=_5w2AQAAMAAJ Volume 3]
⚫
* {{cite web| title=EMF Monitoring on Amtrak's Northeast Corridor: Post-Electrification Measurements and Analysis| author=US Department of Transportation: Federal Railroad Administration| date=October 2006| archive-url=https://web.archive.org/web/20100527153152/http://www.fra.dot.gov/downloads/RRdev/rdv0601.pdf| url=http://www.fra.dot.gov/downloads/RRdev/rdv0601.pdf| archive-date=May 27, 2010| access-date=December 26, 2010| ref={{SfnRef|EMF}}}}
* {{cite conference |last=Agarwal |first=K.K. |title=Automatic fault location and isolation system for the electric traction overhead lines |conference=2002 ASME/IEEE Joint Railroad Conference |date=2002 |pages=117 |doi=10.1109/RRCON.2002.1000103}}.
⚫
* ''Audit Report of Amtrak's High Speed Rail Electrification Project'', US Department of Transportation: Federal Railroad Administration, December 1999. [https://web.archive.org/web/20110721040739/http://www.oig.dot.gov/library-item/4831 Retrieved] 12/26/2010.
⚫
* Chance, E.E. "System Compatibility of the HST", ''Railroad Conference, 1997., Proceedings of the 1997 IEEE/ASME Joint'', pp 1–9, 1997. {{doi|10.1109/RRCON.1997.581346}}.
⚫
* ''EMF Monitoring on Amtrak's Northeast Corridor: Post-Electrification Measurements and Analysis'', US Department of Transportation: Federal Railroad Administration, October 2006. [https://web.archive.org/web/20100527153152/http://www.fra.dot.gov/downloads/RRdev/rdv0601.pdf Retrieved] 12/26/2010.
⚫
* Natarajan, R.; Imece, A.F.; Popoff, J.; Agarwal, K.; Meliopoulos, S. "Approach to the analysis of Amtrak's systemwide grounding of the Northend Electrification Project", ''Power Engineering Society Summer Meeting, 1999'', Vol 1, pp.&nbsp;451–456. {{doi|10.1109/PESS.1999.784390}}.
* Sutherland, et al. ''Analysis of Harmonics, Flicker and Unbalance of Time-Varying Single-Phase Traction Loads on a Three-Phase System'', Paper No. IPST05 - 091. [https://web.archive.org/web/20110718120505/http://www.ipst.org/TechPapers/2005/IPST05_Paper091.pdf Retrieved] 12/26/2010.


== Further reading ==
⚫
[[Category:Amtrak|60]]
⚫
* Environmental Impact Statement: [https://books.google.com/books?id=CJ02AQAAMAAJ Volume 1], [https://books.google.com/books?id=0rY2AQAAMAAJ Volume 2], [https://books.google.com/books?id=_5w2AQAAMAAJ Volume 3]
⚫
* {{cite web| title=Audit Report of Amtrak's High Speed Rail Electrification Project| author=US Department of Transportation: Federal Railroad Administration| date=December 1999| archive-url=https://web.archive.org/web/20110721040739/http://www.oig.dot.gov/library-item/4831| url=http://www.oig.dot.gov/library-item/4831| archive-date=July 21, 2011| access-date=December 26, 2010}}
⚫
* {{cite journal| last=Chance| first=E.E.| title=System Compatibility of the HST| journal=Railroad Conference, 1997., Proceedings of the 1997 IEEE/ASME Joint| pages=1–9| date=1997}} {{doi|10.1109/RRCON.1997.581346}}.
* {{cite conference |first1=P. E. |last1=Sutherland |first2=M. |last2=Waclawiak |first3=M. F. |last3=McGranaghan |title=Analysis of Harmonics, Flicker and Unbalance of Time-Varying Single-Phase Traction Loads on a Three-Phase System |id=IPST05 - 091 |date=June 2005 |s2cid=24727674 |book-title=Proceedings of the International Conference on Power Systems Transients 2005 | archive-url=https://web.archive.org/web/20110718120505/http://www.ipst.org/TechPapers/2005/IPST05_Paper091.pdf| url=http://www.ipst.org/TechPapers/2005/IPST05_Paper091.pdf| archive-date=July 18, 2011 |url-status=live}}

{{Amtrak}}

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[[Category:25 kV AC railway electrification]]
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[[Category:Amtrak|60 Hz traction power system]]
[[Category:Electric railways in Connecticut]]
[[Category:Electric railways in Connecticut]]
[[Category:Electric railways in Rhode Island]]
[[Category:Electric railways in Rhode Island]]
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[[Category:Traction power networks]]
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[[Category:Railway electrification in the United States]]
[[Category:Railway electrification in the United States]]
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[[Category:25 kV AC railway electrification]]

Latest revision as of 22:24, 14 August 2024

An AEM-7 electric locomotive brings an Amtrak train into South Station, Boston, in 2001

Amtrak’s 60 Hz traction power system operates along the Northeast Corridor between New Haven, Connecticut,[note 1] and Boston, Massachusetts. This system was built by Amtrak in the late 1990s and supplies locomotives with power from an overhead catenary system at 25 kV alternating current with at 60 Hz, the standard frequency in North America. The system is also known as the Northend Electrification, in contrast to Amtrak's 25 Hz traction power system that runs between New York City and Washington, D.C., which is known as the Southend Electrification system.

History

[edit]

In 1992, Congress passed the Amtrak Authorization and Development Act requiring Amtrak to establish high-speed rail passenger service between New York City and Boston. The goal was to reduce travel time in this corridor from 4.5 hours to less than 3 hours. Revenue from this service was expected to play a critical role in helping Amtrak achieve operating self-sufficiency by 2003. Before Amtrak could begin high-speed rail service, 155 miles (249 km) of rail line between New Haven and Boston had to be electrified. Previously, electrified Metroliner service was available between Washington, D.C., and New Haven, Connecticut. At New Haven, Amtrak had to switch to a diesel locomotive to complete the trip to Boston. In addition to the higher operating speeds possible with electrified service, Amtrak also saves the time it spent on switching locomotives. By the time the project was complete, Amtrak was expected to have spent over $600 million to electrify the line between New Haven and Boston.[1] Including extensive track and infrastructure improvements besides the electrification, the project cost $1.6 billion.[2]

In December 1995, Amtrak awarded a $321 million contract to Balfour Beatty Construction, Inc./Mass. Electric Construction (BBC/MEC) to verify and complete the Morrison-Knudsen design and build the electrification system. The system was to be completed by June 1999; electrification system ground-breaking ceremony took place the following July.

Approach to South Station, Boston, showing electrified track (left) and the massive complex of roads that were under construction at the same time as the electrification.

Amtrak's contractor faced a difficult working environment in the Boston Terminal Area because of the extensive work being undertaken for the Central Artery project, which involved over 500 employees in the South Boston Terminal area alone and entailed on-site storage of a large amount of heavy construction equipment and supplies. The Central Artery project was ongoing before the electrification project started. Another factor complicating electrification work in the Boston Terminal Area is the large volume of rail traffic. Over 250 Massachusetts Bay Transportation Authority (MBTA) commuter trains and 20 Amtrak trains operate through the area daily. As a result, taking track out of service to work on the electrification was sometimes difficult.

Electrification work on the five movable bridges between Old Saybrook and Mystic in Connecticut was also a challenge, as each one required a unique electrification design and construction solution. The bridges span busy waterways shared by pleasure craft, commercial carriers, and military traffic. Unlike most movable highway bridges, these bridges are usually open, and are closed only to accommodate approaching train traffic.[1]

After several delays, service with electric locomotives between New Haven and Boston began on January 31, 2000.[3] Amtrak began operating its higher-speed Acela Express service on December 11, 2000.[4]

Types of stations

[edit]

System architecture

[edit]
A catenary pole of the system. Catenary wires and contact wires are tensioned by individual tension balancers.

The basic system unit is an elementary electrical section consisting of a segment of one or more parallel tracks, each with a contiguous contact (or catenary or trolley) wire for the locomotive pantograph and an electrically separate feed wire. Elementary electrical sections are separated by section breaks where the contact and feeder wires can be interrupted with motor-operated air switches to isolate a section in the event of a fault or to permit maintenance.

An electrical section is a collection of elementary electrical sections, section breaks, air switches and paralleling stations between a substation and a switching station.

At each substation, utility-supplied single phase power is transformed and injected into the two electrical sections terminating at that substation. There are eight electrical sections in the system, two for each substation. The substations drive the contact and feed wires in a split phase arrangement so that each wire is at 25 kV with respect to the grounded running rails with 50 kV between them.

At periodically spaced paralleling stations within each electrical section the tracks' catenary wires are connected together to one side of an autotransformer and the feeder wires are connected together to the other side of the autotransformer. The autotransformer center tap is connected to the grounded running rails that return the current from the locomotives. The paralleling stations thus reduce voltage drops by feeding a locomotive from both directions along its contact wire and spreading the load across all the contact and feed wires of a multitrack system. The split-phase arrangement also gains the increased efficiency of operating at 50 kV while the highest voltage with respect to ground remains only 25 kV. (The same split-phase method is used in North American homes to supply high power loads such as air conditioners with the efficiency of a 240 V supply while retaining the safety advantages of a 120 V supply.)

Substations

[edit]

There are four substations between New Haven and Boston:

  • Branford, CT
  • New London, CT
  • Warwick, RI
  • Sharon, MA

Each station contains two 115 kV (single phase) to 50 kV (single phase with center tap) transformers to convert the utility supplied transmission voltage to 50 kV traction voltage. Output circuit breakers, and a capacitor based filter network are installed. The filter banks suppress the high frequency (that is anything above 60 Hz) harmonics on the catenary lines generated by locomotives' solid-state traction motor inverters. The filters also provide reactive power support and correct for power factor. Amtrak's 60 Hz electrification distributes power using ±25 kV from ground via a center tap of the 115/50 kV transformers. This system is also known as 2 × 25 kV.

Switching stations

[edit]

Three switching stations are the equivalent of distribution level substations, which transform higher voltage electricity to the 25 kV voltage, and are located along the line which separate the different electrical sections (power zones):

  • Westbrook, CT
  • Richmond, RI
  • Norton, MA

The switching stations contain three autotransformers similar to the paralleling stations (which have one), and also have additional circuit breakers to allow segmentation of catenary and cross-connection between power zones.

Electrical sections encompass both tracks between a substation and the adjacent switching stations. Normally no power flows from one side of a switching station to the other side; it is like two adjacent paralleling stations which serve different electrical sections. In the event that a substation is taken out of service, switching stations have additional circuit breakers which allow feeding an electrical section from the adjacent section.

Since switching stations, like substations, normally separate electrical sections with different supply sources (and thus different phase or voltage), a neutral section[note 2] always occupies the track between the two electrical sections.

In the event of a fault in one elementary electrical section, the switching station can 'back-feed' the far portion of the affected track from the non-affected track, which the supplying substation feeds the near end.

Paralleling stations

[edit]
Stonington Paralleling Station
Noank Paralleling Station

Eighteen paralleling stations are located at approximately six mile intervals[6] along the line. Each contains a single autotransformer (with the exception of Roxbury, which has two), automatic circuit breakers, motor-operated air switches, and a control shed. The autotransformers are rated at 10 MVA, 1.2% impedance, two winding, 27.5 kV.[7]

Each paralleling station bus is connected to both north and south track catenary and feeder lines via automatic circuit breakers. The autotransformer is connected to the bus bars by an additional circuit breaker. The track breakers at the paralleling stations trip on sensing no-voltage. Thus when a line fault causes the supplying substation breakers to trip, the paralleling stations also trip. This action separates the two tracks from one another electrically and allows the substation to automatically restore one of the tracks (the non-faulted one). After a variable time delay (to reduce simultaneous inrush current), over-voltage relays will re-shut the track circuit breakers on the non-faulted track.

List of stations

[edit]
Schematic of substations along the Northend Electrification
Map all coordinates using OpenStreetMap

Download coordinates as:

Amtrak Northend Electrification Stations
MP[8] State Municipality Type Coordinates Comments
228.49 MA Boston (South Station) N/A End of electrification
226.12 MA Roxbury Paralleling station 42°19′59″N 71°05′37″W / 42.3331°N 71.0937°W / 42.3331; -71.0937 (Roxbury paralleling station)
219.08 MA Readville Paralleling station 42°14′11″N 71°08′03″W / 42.2365°N 71.1343°W / 42.2365; -71.1343 (Readville paralleling station)
212.36 MA Sharon Substation 42°08′39″N 71°09′51″W / 42.1442°N 71.1642°W / 42.1442; -71.1642 (Sharon substation)
204.98 MA East Foxboro Paralleling station 42°02′44″N 71°12′39″W / 42.0456°N 71.2107°W / 42.0456; -71.2107 (East Foxboro paralleling station)
198.68 MA Norton Switching station 41°58′08″N 71°15′55″W / 41.969°N 71.2652°W / 41.969; -71.2652 (Norton switching station)
193.41 MA Attleboro Paralleling station 41°54′13″N 71°19′22″W / 41.903555°N 71.322914°W / 41.903555; -71.322914 (Attleboro paralleling station)
187.60 RI Providence Paralleling station 41°51′38″N 71°24′23″W / 41.860604°N 71.406251°W / 41.860604; -71.406251 (Providence paralleling station)
181.89 RI Elmwood Paralleling station 41°47′53″N 71°25′43″W / 41.798065°N 71.42868°W / 41.798065; -71.42868 (Elmwood paralleling station)
176.94 RI Warwick Substation 41°43′57″N 71°26′26″W / 41.732459°N 71.440597°W / 41.732459; -71.440597 (Warwick substation)
169.82 RI East Greenwich Paralleling station 41°38′04″N 71°27′50″W / 41.634505°N 71.463999°W / 41.634505; -71.463999 (East Greenwich paralleling station)
161.81 RI Exeter Paralleling station 41°31′33″N 71°31′08″W / 41.525942°N 71.518782°W / 41.525942; -71.518782 (Exeter paralleling station)
157.15 RI Kingston Paralleling station 41°28′32″N 71°34′29″W / 41.475541°N 71.57462°W / 41.475541; -71.57462 (Kingston paralleling station)
150.15 RI Richmond Switching station 41°26′15″N 71°41′24″W / 41.437637°N 71.689892°W / 41.437637; -71.689892 (Richmond switching station)
145.19 RI Bradford Paralleling station 41°23′41″N 71°45′39″W / 41.394712°N 71.760969°W / 41.394712; -71.760969 (Bradford paralleling station)
139.97 CT State Line Paralleling station 41°21′52″N 71°50′25″W / 41.3644°N 71.8403°W / 41.3644; -71.8403 (State Line paralleling station)
134.70 CT Stonington Paralleling station 41°20′25″N 71°55′31″W / 41.3403°N 71.9254°W / 41.3403; -71.9254 (Stonington paralleling station)
129.50 CT Noank Paralleling station 41°19′24″N 71°59′54″W / 41.3234°N 71.9984°W / 41.3234; -71.9984 (Noank paralleling station)
123.56 CT New London Substation 41°21′46″N 72°05′35″W / 41.3629°N 72.093°W / 41.3629; -72.093 (New London substation) Transformers are grade separated from roadbed; catenary feeders run underground.
117.54 CT Millstone Paralleling station 41°18′59″N 72°09′52″W / 41.3164°N 72.1644°W / 41.3164; -72.1644 (Millstone paralleling station)
109.30 CT Old Lyme Paralleling station 41°17′48″N 72°18′16″W / 41.2966°N 72.3044°W / 41.2966; -72.3044 (Old Lyme paralleling station)
103.10 CT Westbrook Switching station 41°17′24″N 72°24′40″W / 41.2900°N 72.4112°W / 41.2900; -72.4112 (Westbrook switching station)
98.87 CT Grove Beach Paralleling station 41°16′36″N 72°29′15″W / 41.2768°N 72.4875°W / 41.2768; -72.4875 (Grove Beach paralleling station)
92.19 CT Madison Paralleling station 41°17′02″N 72°36′40″W / 41.2840°N 72.6112°W / 41.2840; -72.6112 (Madison paralleling station)
86.10 CT Leetes Island Paralleling station 41°15′56″N 72°43′30″W / 41.2655°N 72.7250°W / 41.2655; -72.7250 (Leetes Island paralleling station)
78.96 CT Branford Substation 41°17′03″N 72°51′13″W / 41.2841°N 72.8537°W / 41.2841; -72.8537 (Branford substation) Transformers located N. of I-95.
73.6 CT Mill River Interlocking N/A 41°18′41″N 72°54′42″W / 41.311281°N 72.911775°W / 41.311281; -72.911775 (Mill River Interlocking (southern end of Amtrak 25 kV electrification)) End of 25 kV, 60 Hz system

See also

[edit]

Notes

[edit]
  1. ^ Specifically, Amtrak's 25 kV system begins at the Mill River Interlocking about two miles north of New Haven Union Station 41°18′41″N 72°54′42″W / 41.311281°N 72.911775°W / 41.311281; -72.911775 (Mill River Interlocking (Southern End of Amtrak 25 kV Electrification))
  2. ^ The terms 'phase break', 'neutral section', and 'dead section' are colloquially interchanged. Agarwal refers to these as 'neutral sections'.[5] In the ex-PRR portions of Amtrak's system, they would be known as 'dead sections'.

References

[edit]
  1. ^ a b Federal Railroad Administration Inspector General (December 14, 1999). "Report on Amtrak's High-Speed Rail Electrification Project" (PDF). Retrieved September 28, 2017. Report No: RT-2000-020
  2. ^ Lueck, Thomas J. (March 10, 1999). "Amtrak Unveils Its Bullet to Boston". New York Times.
  3. ^ Middleton, William D. (March 2003). "Super Railroad". Trains. 63 (3): 36–59. ISSN 0041-0934.
  4. ^ "Amtrak's new Hit-Speed Service is Derailed by Mechanical Problem". Los Angeles Times. Associated Press. December 13, 2000.
  5. ^ Agarwal, K.K. (2002). "Automatic fault location and isolation system for the electric traction overhead lines". ASME/IEEE Joint Railroad Conference. 2002 ASME/IEEE Joint Railroad Conference. pp. 117–122. doi:10.1109/RRCON.2002.1000103. ISBN 0-7803-7452-5..
  6. ^ EMF, p. 5.
  7. ^ Natarajan et al. 1999, p. 453.
  8. ^ Natarajan et al. 1999, p. 451.

Works cited

[edit]

Further reading

[edit]
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