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82-504: Two of the turbine units are dedicated to generating for Amtrak's 25 Hz traction power system , and the facility also has a frequency converter available for conversion of power between 25 Hz and the 60 Hz used by the electric grid. The mixed marshy terrain of the Conejohela Valley contained rapids and small waterfalls, wetlands, and thick woods along both sides of the river within a ten-year floodplain which saw annual inundations all

164-416: A common shaft with different ratios of poles; they are not electrically connected as in a true rotary converter. Principal advantages of motor generators include very high fault current ratings and clean output current. Solid state electronics can be damaged very quickly, so the microprocessor control systems react very quickly to over-correct conditions to place the converter in a safe, idle mode or to trip

246-415: A constant rate over the entire year (although it is not in practice), the average system load would be approximately 63 MW. The system power factor varies between 0.75 and around 0.85. Electrical power originates at seven generation facilities or traction current converter plants . The nameplate capacity of all the power sources in the system is about 354 MW. The instantaneous peak loading on

328-574: A filter. These attributes, combined with their high fault-current capability, make them desirable in a stabilizing role within the power system. Amtrak has retained two of the original converter plants and plans to overhaul them and continue their operation indefinitely. Disadvantages of motor generators include lower efficiency, generally between 83% (lightly loaded machine) and 92% (fully loaded machine). In comparison, cycloconverter efficiency can exceed 95%. Also, motor generators require more routine maintenance due to their nature as rotating machines, given

410-497: A majority of the transmission infrastructure is located directly above the rail lines on the same structure that supports the catenary system, some lines are either located above lines that have been de-electrified or abandoned or, in a few cases, on completely independent rights of way. The following is a list of all major segments of the 25 Hz 138 kV transmission infrastructure listing substations (SS or Sub) or high-tension switching stations (HT Sw'g) as termini. For clarity,

492-512: A portion of its Main Line in 1908 at 11 kV 25 Hz AC and this served as a template for the PRR, which installed its own trial main line electrification between Philadelphia and Paoli, Pennsylvania in 1915. Power was transmitted along the tops of the catenary supports using four single phase , two wire 44 kV distribution circuits. Tests on the line using experimental electric locomotives such as

574-493: A rule as single leaders. For the supply of railways with much rail traffic and in particular for the power supply of high speed railway lines such as the German ICE (Inter City Express) trains, conductors of two bundles are used. The traction current lines from the nuclear power station at Neckarwestheim to the traction current switching station at Neckarwestheim, and from the traction current switching station at Neckarwestheim to

656-523: Is a small 55 kV single phase AC network for power supply of trains in the South, fed by Hakavik Power Station . A further power station, at Kjofossen feeds single phase AC directly in the overhead wire. In Denmark and Finland , 50 Hz is used for the main lines (if electrified) and the electricity comes from general suppliers. As such, much simpler equipment than in Sweden and Norway is needed for conversion. In

738-507: Is an electricity grid for the supply of electrified rail networks . The installation of a separate traction network generally is done only if the railway in question uses alternating current (AC) with a frequency lower than that of the national grid, such as in Germany , Austria and Switzerland . Alternatively, the three-phase alternating current of the power grid can be converted in substations by rotary transformers or static inverters into

820-425: Is common to find pylons which carry electric circuits for traction current as well as those for three-phase alternating current. The latter can be 110 kV, 220 kV, or, in some cases, 380 kV three phase AC lines. In such cases, the traction current lines must use insulators which can cope with the maximum peak-to-peak voltage which can occur between the lines. Traction current lines are implemented as

902-498: Is connected to substations along the line of the railway and is usually run separately from the overhead catenary wire from which the locomotives are fed. In countries in which the electric trains run with direct current or with single-phase alternating current with the frequency of the general power grid, the required conversion of the current is performed in the substations, so again no traction current lines are required. Traction current supply lines are not usually laid parallel to

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984-584: Is dispatched through the PJM Interconnection , one of many regional transmission organizations feeding the nations power grids. On May 18, 2001, President George W. Bush visited the Safe Harbor Hydroelectric plant to expound on his just-unveiled National Energy Policy. Safe Harbor was chosen as an example of government, corporate, and environmental groups working together in energy generation. In 2001, Safe Harbor Water Power Corporation won

1066-407: Is impossible for the 138 kV transmission system to protect or reconfigure itself during a fault condition. High voltage faults generally are cleared by opening converter output breakers, which causes a concurrent loss of the converter. The system does not degrade gracefully under high-voltage faults. Rather than isolating, for example, the south 138 kV feeder between Washington and Perryville,

1148-638: Is known as the Northend Electrification system. In 1976, Amtrak inherited the system from Penn Central , the successor to the Pennsylvania Railroad, along with the rest of the NEC infrastructure. Only about half of the system's electrical capacity is used by Amtrak; the remainder is sold to the regional railroads that operate their trains along the corridor, including NJ Transit , SEPTA and MARC . The system powers 226.6 miles (364.7 km) of

1230-607: Is no reason today to apply different frequencies or current types than for transmission and for industrial usage. However, the advantage with DC traction was the easier transmission with single copper wires to the feeder points. The advantage with AC traction is the easier transmission over long distances to the feeder points. Beyond these parameters and securing former investment, no evidence exists to stay with different current schemes in networks. Dedicated traction current lines are used when railways are supplied with low-frequency alternating current (AC). The traction current supply line

1312-418: Is standard at traction current lines, cannot be used. Where four conductors are needed, one approach is to employ a two-level arrangement of conductor cables. Alternatively, in cases of double-tracked railway lines, the overhead line pylons for both driving directions are equipped with cross beams for the traction current system (two conductor cables). In densely populated areas, where rights of way are rare, it

1394-687: Is the Mariazeller narrow gauge railway in Austria, operating with single phase AC with a frequency of 25 Hz, which has its own traction current lines with an operating voltage of 27 kV. These lines are mounted on the pylons of the overhead wire over the lines. The voltages used for traction current lines are 110  kV in Germany and Austria and 66 kV or 132 kV in Switzerland. Traction current lines are operated symmetrically against earth . In

1476-490: The PRR FF1 revealed that the 44 kV distribution lines would be insufficient for heavier loads over longer distances. In the 1920s, the PRR decided to electrify major portions of its eastern rail network, and because a commercial electric grid did not exist at the time, the railroad constructed its own distribution system to transmit power from generating sites to trains, possibly hundreds of miles distant. To accomplish this,

1558-409: The former GDR three phase AC from the public grid is converted into single phase AC with a frequency of 16.7 Hz in substations close to the railways. In these regions there are no traction current lines. Also in countries in which the electric trains run with direct current or with single phase AC with the frequency of the general power grid, the required conversion of the current is performed in

1640-407: The pylons as a rule (in contrast with three-phase alternating current lines, whose number of conductors are an integral multiple of three). Traction current lines are not usually laid parallel to the railway line, so as to minimise the line length and to avoid unnecessary influences of electrical system near the railway line. However, there are cases where this practice is not followed (for example,

1722-436: The trans-Hudson tunnels and New York Penn Station . These initial systems were low-voltage direct current (DC) third rail systems. While they performed adequately for tunnel service, the PRR ultimately found it inadequate for long-distance, high-speed electrification. Other railroads had, by this time, experimented with low frequency (less than 60 Hz) alternating current (AC) systems. These low-frequency systems had

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1804-414: The 12 kV catenary wire, the 138 kV lines were installed on new steel monopod poles installed along the right-of-way. Except for the fact that the new poles only carry four conductors rather than the typical six for a utility line, the new line appears as a typical medium voltage power line rather than the typical PRR-style H-shaped structure. In 2011, Amtrak replaced the transmission lines that tie

1886-435: The 132 kV terminations and switchgear . By 1935, new stations were connected to remote supervision systems, allowing power directors to open and close switches and breakers from central offices without having to go through the tower operators. Today, about 55 substations are part of Amtrak's network. Substations are spaced on average 8 miles (13 km) apart and feed 12 kV catenary circuits in both directions along

1968-533: The 1730 opening of the historic Wright's Ferry and (later the first two) Columbia-Wrightsville Bridges , once believed to be the longest covered bridges in the world. The dam is located just above the confluence of the Conestoga River with the Susquehanna, about 7 miles (11 km) downstream of Washington Boro , Pennsylvania , which at mid-river is figured more or less the center of Lake Clarke created by

2050-441: The 25 Hz and 60 Hz sides, and lower overload capability. The majority of power sources in the original Pennsylvania Railroad electrification were built prior to 1940. Some have been retired outright, others have been replaced with co-located static frequency converters, and others remain in service and will be refurbished and operated indefinitely. The following tables lists sources which are no longer in service: During

2132-673: The 25 Hz power output is dispatched to Amtrak's substation in Perryville, Maryland via four circuits. The remaining third of output is transmitted by two circuits to substations in Royalton and Parkesburg , Pennsylvania. The facility also has a motor-generator frequency converter which can convert any excess 25 Hz power to 60 Hz or can convert 60 Hz power to 25 Hz when needed. The remaining twelve units generate 60 Hz, three-phase power. Safe Harbor can generate 417.5 megawatts of hydroelectric power . Power from Safe Harbor

2214-443: The 44 kV distribution voltage to 11 kV catenary voltage. The substations were operated from adjacent signal towers. They used typical period concrete buildings to house the transformers and switchgear while the line terminals were on the roof. From 1918 onward, outdoor stations were used, and when the main line electrification began in 1928, the stations became large open-air structures using lattice steel frameworks to mount

2296-470: The AC advantage of higher transmission voltages, reducing resistive losses over long distances, as well as the typically DC advantage of easy motor control as universal motors could be employed with transformer tap changer control gear. Pantograph contact with trolley wire is also more tolerant of high speeds and variations in track geometry . The New York, New Haven and Hartford Railroad had already electrified

2378-699: The Conestoga Substation to Parkesburg via Atglen. These lines were originally installed over the Atglen and Susquehanna Branch . The line was subsequently abandoned by Conrail and the tracks removed, but Amtrak has retained an easement to operate its 138 kV transmission lines over the roadbed. Towers and conductors and wire over 24 miles (39 km) of the route were replaced; work was completed in September 2011. The scope of work included: Traction power network A traction network or traction power network

2460-651: The Governor's Award for Environmental Excellence. The award citation states that Safe Harbor had removed over 11,000 tons of debris from the river and was able to recycle almost all of it. Amtrak%27s 25 Hz traction power system Amtrak's 25 Hz traction power system is a traction power network for the southern portion of the Northeast Corridor (NEC), the Keystone Corridor , and several branch lines between New York City and Washington D.C. The system

2542-415: The NEC between New York City and Washington, D.C., the entire 104-mile (167 km) Keystone Corridor, a portion of NJ Transit's North Jersey Coast Line (between the NEC and Matawan), along with the entirety of SEPTA's Airport , Chestnut Hill West , Cynwyd , and Media/Wawa lines. The Pennsylvania Railroad (PRR) began experimenting with electric traction in 1910, coincident with their completion of

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2624-471: The PRR implemented a pioneering system of single-phase high voltage transmission lines at 132 kV, stepped down to the 11 kV at regularly spaced substations along the tracks. The first line to be electrified using this new system was between Philadelphia and Wilmington, Delaware in the late 1920s. By 1930, catenary extended from Philadelphia to Trenton, New Jersey , by 1933 to New York City, and by 1935 south to Washington, D.C. Finally, in 1939,

2706-430: The PRR installed two 11 kV, 4.5 MVA synchronous converters at Radnor , the approximate center point of the system load. This substation was located at the site of water tanks used to supply water to track pans, which supplied water to conventional steam locomotives. At some later time, the converters were shut down and removed. Dedicated machines for reactive power support have not been used subsequently by either

2788-508: The PRR or Amtrak. 40°02′41″N 75°21′34″W  /  40.044725°N 75.359463°W  / 40.044725; -75.359463  ( Radnor ) The PRR's original 1915 electrification made use of four substations at Arsenal Bridge , West Philadelphia , Bryn Mawr , and Paoli . The Arsenal Bridge substation stepped-up 13.2 kV, 25 Hz power supplied from PECO's Schuylkill power station on Christian Street to 44 kV for distribution. The remaining three substations reduced

2870-738: The PRR's AC system around 1938 when ConEd assumed operation of the Long Island City Station. The single-phase turbine generators were retired in the mid-1970s due to safety concerns. Two transformers were installed to supply catenary power from the remaining (three-phase) portions of ConEd's still relatively extensive 25 Hz system. Power flow management problems prevented usage of this source under other than emergency conditions. 40°44′47″N 73°58′15″W  /  40.7464°N 73.9707°W  / 40.7464; -73.9707  ( Waterside Generating Station (Demolished) ) In 1986, Baltimore Gas and Electric elected not to renew

2952-442: The PRR's system to the utility grid standard of 60 Hz. Ultimately, this plan was shelved as economically unfeasible, and the electrical traction infrastructure was left largely unchanged with the exception of a general traction power voltage increase to 12 kV and a corresponding transmission voltage increase to 138 kV. During the 1970s, several of the original converter or power stations that originally supplied power to

3034-815: The Republic of South Africa there are extensive AC and DC traction schemes, including 50 kV and 25 kV AC single phase systems. Electrification in Natal was stimulated by the takeover of the South African Railways' system by the Electricity Supply Commission (now Eskom ) based on the Colenso Power Station . In the United Kingdom , the Network Rail 750 V DC electrification system in

3116-527: The adjacent Waterside Generating Station, most likely due to declining overall demand for 25 Hz power. The station was disused and sold in the mid-1950s. 40°44′35″N 73°57′29″W  /  40.7430°N 73.9581°W  / 40.7430; -73.9581  ( Long Island City Generating Station (Disused) ) Originally constructed by Consolidated Edison to supply power to their DC distribution system in Manhattan, Waterside began supplying power to

3198-489: The approaches to Union Station and decreased system reliability. The Ivy City project resulted in the installation of two 4.5 MVA transformers in a 138/12 kV substation on the northeast edge of the Ivy City yard complex and 5.2 miles (8.4 km) of 138 kV transmission line to augment the overstretched facilities at Landover. Since the original catenary supports along this section of track were only high enough for

3280-690: The bearings and slip rings. Today, the outright replacement of motor generators would also be difficult due to the high manufacturing cost and limited demand for these large 25 Hz machines. The static converters in the system were commissioned during the decade between 1992 and around 2002. Static converters use high-power solid-state electronics with few moving parts. Chief advantages of static converters over motor generators include lower capital cost, lower operating costs, and higher conversion efficiency. The Jericho Park converter exceeds its efficiency design criteria of 95%. Major disadvantages of solid state converters include harmonic frequency generation on both

3362-518: The beginning of the 20th century, 25 Hz power was much more readily available from commercial electrical utilities. The vast majority of urban subway systems used 25 Hz power to supply their lineside rotary converters used to generate the DC voltage supplied to the trains. Since rotary converters work more efficiently with lower-frequency supplies, 25 Hz was a common supply frequency for these machines. Rotary converters have been steadily replaced over

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3444-518: The case of 110 kV lines, for example, each conductor has a voltage of 55 kV against earth. The grounding is made in larger substations and in power stations for traction current, using transformers for the cancellation of the earth leakage current . As is the case for all symmetrical powerlines there are also at traction power lines twisting points. A traction powerline for one circuit has usually two conductors. Since most traction current lines possess two electric circuits, four conductors are on

3526-562: The catenary wire. In Germany , single conductors are usually used for traction current lines but, for the ICE train, two bundle conductors are used. The traction current supply lines from the nuclear power station Neckarwestheim to the traction current switching station at Neckarwestheim and from there to the central substation in Stuttgart , Zazenhausen are implemented as a four-bundle conductor circuit. In Sweden , Norway and some areas of

3608-635: The central substation in Stuttgart Zazenhausen are implemented as four-bundle conductors. Traction current lines are always equipped with an earth conductor. In some cases, two earth conductors are used: for example in, Germany, in cases where the traction current line is carried on pylons together with three phase AC, like the line to the nuclear power station at Neckarwestheim. Similarly, in Austria there are some traction current lines equipped with two earth ropes. In Sweden , Norway and some areas of

3690-563: The contract under which it had operated the Benning Power Station frequency changer on behalf of Amtrak. They proposed a static frequency changer, which was built at Jericho Park ( Bowie, Maryland ) and placed on service in the spring of 1992. 38°53′51″N 76°57′33″W  /  38.897534°N 76.959298°W  / 38.897534; -76.959298  ( Benning Frequency Changer ( demolished) ) Although reactive power has primarily been supplied along with real power by

3772-468: The current supply of some rapid-transit railways operating with alternating current in Germany). In this case, the traction current line is laid on special cross beams of the overhead wire pylons above the overhead line. Because overhead line pylons possess a smaller cross section than traction current masts, these cross beams have to be quite narrow, so the arrangement of four conductor cables in one level, which

3854-412: The dam are scheduled by Amtrak but operated by Safe Harbor Water Power Company. Like other hydroelectric plants, it has excellent black start capability which was most recently demonstrated during a 2006 blackout. After a cascade shutdown of converters had left the network de-energized, it was recovered using Safe Harbor's generators, and the other converters were subsequently brought back online. During

3936-473: The dam – which has become very popular for water sports and fishing. Ecologically, the varying depth of inundated islands on the bottom of the lake create a succession of valuable varied habitats that support numerous freshwater feeder fish, pan fish, and large predatory game fish species. Thus, the bird-small animal habitat that was lost was replaced, by and large, by freshwater lacustrine habitats. LS Power Group purchased PPL's share in 2011, and

4018-485: The electrical frequency conversion equipment, but the lineside transmission and distribution equipment were unchanged. In 2003, Amtrak commenced a capital improvement plan that involved planned replacement of much of the lineside network, including 138/12 kV transformers , circuit breakers , and catenary wire. Statistically, this capital improvement has resulted in significantly fewer delays, although dramatic system shutdowns have still occurred. The 25 Hz system

4100-657: The former German Democratic Republic , three phase AC is converted into single phase AC with a frequency of 16.7 cycles per second at the substations. Unlike in Western Germany, there are no dedicated power plants for railway electricity. All power comes from general electricity suppliers. Although in this region there is, in principle, no requirement for traction power lines, there is a 132 kV-single AC power grid for railway power supply in Central Sweden (see Electric power supply system of railways in Sweden ). In Norway, there

4182-630: The future include: The Ivy City substation project marked the first extension of 138 kV transmission line since the Safe Harbor Dam was constructed in 1938. In the original PRR electrification scheme, the 138 kV transmission lines went south from Landover to the Capital South substation rather than following the line through Ivy City to the northern approach to Union Station . The two tracks between Landover and Union Station had no high voltage transmission line above them; Union Station catenary

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4264-443: The line-side substations. Currently, the following converter and generating plants are operable, although all are rarely in operation simultaneously due to maintenance shutdowns and overhauls: Several types of equipment are currently in operation: static inverters , motor–generators (sometimes called rotary frequency converters), water turbines (hydroelectric generators) and a static cycloconverter . The 25 Hz turbines at

4346-488: The line. Thus, the catenary is segmented (via section breaks, also called 'sectionalizations' by the PRR) at each substation, and each substation feeds both sides of a catenary's section break. A train traveling between two substations draws power through both transformers. A typical substation includes two to four 138/12 kV transformers, 138 kV air switches that permit isolation of individual transformers, shutdown of one of

4428-690: The main line from Paoli west to Harrisburg was completed along with several freight-only lines. Also included were the Trenton Cutoff and the Port Road Branch . Superimposed on these electrified lines was an independent power grid delivering 25 Hz current from the point of generation to electric locomotives anywhere on nearly 500 route miles (800 km) of track, all under the control of electric power dispatchers in Harrisburg, Baltimore, Philadelphia and New York City. Northeast railroads atrophied in

4510-418: The nearest substation, which minimizes voltage drop. One disadvantage to the substation design as originally built by the PRR concerns its lack of 138 kV circuit breakers. Essentially, all segmentation of the 138 kV system must be manually accomplished, making rapid isolation of a fault on the 138 kV line difficult. Faults in one part of the line also affect the entire distribution system since it

4592-453: The opening of Pennsylvania Station in Manhattan. The station consisted of 64 coal-fired boilers and three steam turbine generators with a total capacity of 16 MW. In 1910, the station was expanded with two additional turbine generators for a total capacity of 32.5 MW. Power was transmitted to rotary converters (AC to DC machines) for use in the PRR's original third rail electrification scheme. Like most DC electric distribution systems of

4674-500: The original power sources on the PRR traction power network. The last steam turbine shut down in 1954, but some of the original motor generators remain. Although the converting machines are frequently called 'rotary converters' or 'rotary frequency converters,' they are not the rotary converter used frequently by subways to convert low-frequency alternating current to DC power. The converters used are more precisely described as motor generators and consist of two synchronous AC machines on

4756-402: The output circuit breaker . Motor generators, being of 1930s design, are heavily overbuilt. These rugged machines can absorb large load transients and demanding fault conditions while continuing to remain online. Their output waveform is also perfectly sinusoidal without noise or higher harmonic output. They can actually absorb harmonic noise produced by solid-state devices, effectively serving as

4838-672: The overhead line pylons have a smaller cross section than traction current supply masts, the cross beams cannot be too wide, so the standard arrangement of four conductor cables in one level cannot be used. In this case, a two-level arrangement is used, or with two electric circuits for double-railed lines the overhead line pylons for both directions are equipped with cross beams for their own traction current system of two conductor cables each. In densely populated areas, there are pylons which carry circuits for both traction current and for three-phase alternating current for general power. Such lines are found where rights of way are rare. In particular

4920-500: The overhead structure along former Pennsylvania Railroad lines its characteristic 80-foot (24 m)-tall H-shaped structure. They are much taller than the overhead electrification structures on other electrified American railroads due to the 138 kV transmission lines. Catenary towers and transmission lines along former New York, New Haven and Hartford Railroad lines and Amtrak's New England division are much shorter and are recognizable due to different design and construction. While

5002-416: The parallel route of 110 kV and 220 kV three-phase AC is common. The use of 380 kV power lines on the same pylon requires 220 kV insulators for the traction current line, because in case the 380 kV line fails, voltage spikes can occur along the traction current line, which the 110 kV insulators cannot handle. As a rule, traction current lines use single conductors, however for

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5084-537: The past 70 years with, at first, mercury arc rectifiers and, more recently, solid-state rectifiers. Thus, the need for special frequency power for urban traction has disappeared, along with the financial motivation for utilities to operate generators at these frequencies. Long Island City Power Station in Hunter's Point, NY, was built by the Pennsylvania Railroad in 1906 in preparation for the North River Tunnels and

5166-422: The positions of substations are not repeated in this table. A listing of the high-tension switching stations follows. Amtrak's capital improvement program which began in 2003 has continued to the present day and has since 2009 received added support from economic stimulus funding sources (American Recovery and Reinvestment Act of 2009 or ARRA). Major improvements in 2010 included: Major improvements planned for

5248-415: The railway line, in order to allow a shorter line length and to avoid unnecessary influences to the electrical system near the railway line; this also is applied to the current supply of some rapid-transit railways operating with alternating current in Germany. It is also possible to lay out the traction current supply on special cross beams right on the overhead wire pylons above the catenary wire. Because

5330-488: The southeast of England is supplied with power from an extensive 33 kV power distribution network. Traction current lines are used to power the railway systems of countries which use alternating current of a lower frequency than the public supply. This is typically the case in the German-speaking countries of Europe. For example, 16.7  Hz AC is used in Germany , Austria and Switzerland . A specific example

5412-414: The steam turbines and motor generators of the system, the PRR briefly used two synchronous condensers . Shortly after commissioning the 1915 electrification, the railroad discovered that the 44 kV feeders and large inductive loads on the system were causing significant voltage sag. The supplying electric utility ( Philadelphia Electric ) also discovered that power factor correction was needed. In 1917,

5494-455: The supply of railways with high traffic and in particular for the supply of high speed railway lines, two bundle conductors are used. The Mariazell railway in Lower Austria operates on single phase AC at a 25  Hz utility frequency . The railway has its own traction current lines with an operating voltage of 27 kV. These lines are mounted on the pylons of the overhead wire over

5576-457: The system is 210–220 MW (as of c. 2009) during the morning rush hour and up to 225 MW during the afternoon. Peak load has risen significantly over time. In 1997, the peak load was 148 MW. Regardless of the source, all converter and generator plants supply power to the transmission system at 138 kV, 25 Hz, single-phase , using two wires. Typically, at least two separate 138 kV circuits follow each right of way to supply

5658-616: The system were shut down. Also, the end of electrified through-freight service on the Main Line to Paoli allowed the original 1915 substations and their 44 kV distribution lines to be decommissioned with that 20-mile (32 km) section of track being fed from 1930s-era substations on either end. In the decade between 1992 and 2002, several static converter stations were commissioned to replace stations that had or were being shut down. Jericho Park, Richmond, and Sunnyside Yard converters were all installed during this period. This replaced much of

5740-401: The system would require opening converter output breakers at Jericho Park and Safe Harbor. This results in the loss of much more of the network than is required to simply isolate the fault. Download coordinates as: All transmission lines within the 25 Hz system are two-wire, single-phase, 138 kV. The center tap of each 138 kV/12 kV transformer is connected to ground; thus

5822-459: The time ( Thomas Edison 's being the most famous), 25 Hz power was used to drive rotary converters at substations along the line. Some sources state that the station was largely dormant by the 1920s. When AC overhead electrification was extended in the 1930s, Long Island City connected to the 11 kV catenary distribution system. Operation of the station was transferred to Consolidated Edison in 1938, although ConEd began supplying power from

5904-529: The twelve-month period ending August 2009, Safe Harbor supplied about 133 GWh of energy to the Amtrak substation at Perryville. Typically, two-thirds of the Safe Harbor output is routed through Perryville, the remainder being sent through Harrisburg or Parkesburg. This suggests that Safe Harbor supplies around 200 GWh of energy annually into the 25 Hz network. Motor-generators and steam turbine generators were

5986-434: The two 138 kV feeders, or cross-connection from one feeder to another. The output of the transformers is routed to the catenary via 12 kV circuit breakers and air disconnect switches. Cross-connect switches allow one transformer to feed all catenary lines. The PRR substation architecture was based on a long-distance, high-speed railway. The substation spacing ensures that any train is never more than 4 or 5 miles from

6068-401: The two transmission lines are tied to ±69 kV with respect to ground and 138 kV relative to each other. Generally, two separate two-wire circuits travel along the rail line between substations. One circuit is mounted at the top of the catenary poles on one side of the track; the second circuit runs along the other side. The arrangement of catenary supports and transmission wires gives

6150-500: The voltage and type of current required by the trains. For railways which run on direct current (DC), this method is always used, as well as for railways which run on single-phase AC of decreased frequency, as in Mecklenburg-Western Pomerania , Saxony-Anhalt , Norway and Sweden . In these areas there are no traction current networks . Separate power for traction apart from industrial power has historic roots. There

6232-437: The way down into Maryland at the headwaters of Chesapeake Bay , and experienced catastrophic floods regularly (the meaning of a ten-year floodplain). The varied terrain created many interface zones biologically nurturing a great many species. Many of those habitats effectively created difficult walking and horseback terrains, which stifled east-west crossing of the lower Susquehanna in colonial Pennsylvania - Maryland , spurring

6314-460: The years following World War II ; the PRR was no exception. The infrastructure of the Northeast Corridor remained essentially unchanged through the series of mergers and bankruptcies, which ended in Amtrak's creation and acquisition of the former PRR lines, which came to be known as the Northeast Corridor. The circa 1976 Northeast Corridor Improvement Project had originally planned to convert

6396-428: Was built by the Pennsylvania Railroad with a nominal voltage of 11 kV. The nominal operating voltages were raised in 1948 and are now: As of 1997, the system included 951 miles (1,530 km) of 138 kV transmission lines, 55 substations, 147 transformers, and 1,104 miles (1,777 km) of 12 kV catenary. Over 550 GWh of energy is consumed annually by locomotives on the system. If this were consumed at

6478-697: Was constructed by the Pennsylvania Railroad between 1915 and 1938 before the North American power transmission grid was fully established. This is the reason the system uses 25 Hz, as opposed to 60 Hz, which is the standard frequency for power transmission in North America. The system is also known as the Southend Electrification , in contrast to Amtrak's 60 Hz traction power system that runs between Boston and New Haven, which

6560-571: Was fed at 12 kV from the Landover and Capitol substations (the latter via the First Street Tunnels ). When the Capitol South substation was abandoned, coincident with the de-electrification of the track between Landover and Potomac Yard , Union Station and its approaches became a single-end fed section of track. This, combined with rising traffic levels, resulted in low voltage conditions on

6642-492: Was generated on December 7, 1931, and the last of the original seven turbine generator units came on-line on October 14, 1940. Planning for expansion of the generation capacity started in 1981. Construction started on April 12, 1982, and the five new turbine generator units came on-line between April 13, 1985 and April 12, 1986. Units 1 and 2 are Kaplan turbines which are connected to single-phase generators to feed Amtrak's 25 Hz traction power system . Typically, two thirds of

6724-483: Was subsequently purchased in March 2014 by Brookfield Renewable Inc. In May 2014, Brookfield purchased Exelon's share, gaining full ownership. The Safe Harbor Water Power Corporation operates the dam and power plant. Planning for the construction of the Safe Harbor Dam started in 1929, and construction started on April 1, 1930. The dam was completed and closed its gates for the first time on September 29, 1931. The first power

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