Many of us especially this poster has been advocating the upgrade of the PRR style of Catenary to constant tension style to enable higher speed operation. After review of many AMTRAK documents it appears that the upgrades are many years in the future.
A little background is necessary. The PRR built a very robust system in the 1920s and 1930s They used the latest modern electrical designs. The system’s ability to maintain itself for all these years is a compliment to PRR engineering. During WW2 ( time not certain) with the demands of traffic 60Hz to 25Hz frequency converters were found to be needed to supplement the power from the Susquehanna river hydroelectric plants. As the PRR; later PC; then CR decreased their power demands parts of the system that failed were retired and not repaired or replaced. The Federal government continued this practice with AMTRAK till the now increasing demands for power (NJ Transit, SEPTA, MARC, AMTRAK) has hit the available limit. This means any failure may cause voltage drops and consequent slowdowns of present scheduled traffic until repairs can be cobbled together. Remember the POTUS (Obama) used diesels not electric.
The decision of PRR to select 25Hz is lost to history and speculation. Another difference is that the PRR -AMTRAK transmission of system power is not 3 phase but is transmitted 2 wire + ground much like it is to your home. It is single phase with 69Kv to ground on each leg giving a total voltage of 138Kv leg to leg. This system went out of favor as the necessity of 3 phase became apparent. The PRR single phase system is one reason that there is so many transmission lines. The conversion of the readily available 3 phase 60Hz to 25 Hz is the problem.
As long as there is a power shortage the extra power demand from higher speed traffic precludes operating at higher speeds. Remember when PC tested the original METROLINERS they had to test them on Reading RR lines because Reading had a power surplus.
So what is being done to solve this problem? The ARRA (stimulus funds) is paying for several upgrades.
1. A $1.5M frequency stabilization study is being completed.
2. Transmission line upgrades at a price of $45 Million
3. Several Frequency converters added and being rebuilt at price of $81.5 Million
4. Substation rebuilds and additions of $45 Million.
These projects are schedule to completion by Sep 2011.
The next restraint is signaling. Stimulus funds of $60 Million to complete the installation of ACSES signaling on the PRR AMTRAK and the AMTRAK Michigan line; to be completed by September 2011. Without ACSES I believe the top speed is 135 MPH (?). Only 1 Million spent so far on ACSES extension through June. Also 10 Million to add 60 Hz backup power to the 100 Hz PRR signals powered from the 25 Hz CAT power by frequency multipliers. e.
After this upgrade of the power system(s) then the next time funds are available then maybe AMTRAK can spend funds replacing the CAT to constant tension and maybe converting a section at a time to 60 Hz 25Kv. Those of you who have traveled the whole NEC have noted how many fewer transmission lines are present BOS – New Haven.
So all of this can be considered part of the catenary upgrade program and this is where the money should be spent!
I still watch the pre-Conrail videos of all kinds of passenger and freight traffic running on the NEC at all times of the day and it was all electric. Seeing the two E44 engines pulling a long freight and being passed by Metroliner I, GG1, and local commuters all at the same time is breathtaking testament to the whole system.
Amtrak needs to stress the use of hydroelectric power to run the Newark-Washington segments for green nosing points.
This all started with the J.P.Morgan owned New Haven Railroad. In the late 1890s it was "Center Third Rail" in sections of Boston and Hartford at 600 DC power, that got outlawed fast. Bet you thought Lionel Trains invented that, he copied the New Haven.
Faced with the need to go electric, New York had outlawed the steam locomotive from Manhatten, this now required electrification from New York City to Stamford CT, and a later planned extension to New Haven. Entry into GCT in New York City was over New York Central outside third rail, 660 volt DC powered tracks.
Westinghouse sold the New Haven on High Voltage AC power transmission (high voltage small wire)( with AC you can use transformers to keep the power up over long distances). They proposed and built locomotives that employed Series Wound, 660 volt, AC/DC motors. They came out of New York City on DC third rail to Mt. Vernon, the pantographs went up and 11,000 vots of AC power at 25 HTz (cycles) flowed to a step down transformer and then to the AC/DC traction motors. 25HTz ??? In 1907 most commercial power in cities was DC. If you were generating your own power, you could use what worked. As you lower the Frequency (HTz) applied to an AC motor, the motor RPM slows and the Torque increases. You might say the AC motor at 25 HTz acts much like a DC motor. (today VVVF AC drives work much the same way by verying the frequency and applied voltage)
PRR and New Haven joined together to build the Hellgate Bridge and connect the two railroads. When the PRR extended their electrification to Washington and Harrisburg in the 1930s they chose the Westinghouse system.
Today, the 100 year old power plants are mostly gone and with Rectifier Electric Locomotives and DC traction motors 60 HTz (cycle) standard commercial power can be used, the 25 HTz GG1 was dead. Lots of ways to solve power problems, you could even install dual transformers for 25 HTz and 60 HTz in the locomotive.
The cost problem, all the 25 HTz transformers alone the tracks would have to be replaced Contracts with power companies would have to be negated. 60 HTz supply system must be installed. New "Constant Tension Catenary" SHOULD be installed. And get this, any Signal System operating on 60 HTz will need to be replace with a higher frequency system to prevent interferance.
Don U. TCA 73-5735
daveklepper So all of this can be considered part of the catenary upgrade program and this is where the money should be spent!
Yes that appears all part of a long range plan to upgrade the CAT. IMHO this is the correct order of CAT upgrade construction.
One thing omitted was that for each frequency converter this will probably the be the order of operation. Imput 3 phase 60Hz commercial power, go to step down transformers, 3 phase 60Hz, with voltage output unknown to the rotary converter. Then the converter output a 25Hz, single phase, 2 or 3 tap output, voltage unknown fed to step up voltage transformers, then fed to the track side transmission lines. Note: these converters are so big that it appears that the rebuilding will be done on site but again not sure.
In the AMTRAK ARRA funds report there is no mention if AMTRAK is buying dual voltage -- dual frequency equipment that can be used if there is a conversion to 60Hz.( ex. transformers, switch gear, insulators, etc ) Inquiry to AMTRAK could not get an answer. Have not been able to access the specifications of the new equipment. If there is a conversion to 60Hz, 25Kv the old PRR equipment that is replaced at conversion point may be moved to a location that has a 25Hz failure.
All rolling stock that connects to the CAT is now constructed so it can operate on either 12.5Kv 25Hz (11Kv nominal) or 25Kv - 60 Hz power.
blue streak 1daveklepper So all of this can be considered part of the catenary upgrade program and this is where the money should be spent! Yes that appears all part of a long range plan to upgrade the CAT. IMHO this is the correct order of CAT upgrade construction. One thing omitted was that for each frequency converter this will probably the be the order of operation. Imput 3 phase 60Hz commercial power, go to step down transformers, 3 phase 60Hz, with voltage output unknown to the rotary converter. Then the converter output a 25Hz, single phase, 2 or 3 tap output, voltage unknown fed to step up voltage transformers, then fed to the track side transmission lines. Note: these converters are so big that it appears that the rebuilding will be done on site but again not sure. In the AMTRAK ARRA funds report there is no mention if AMTRAK is buying dual voltage -- dual frequency equipment that can be used if there is a conversion to 60Hz.( ex. transformers, switch gear, insulators, etc ) Inquiry to AMTRAK could not get an answer. Have not been able to access the specifications of the new equipment. If there is a conversion to 60Hz, 25Kv the old PRR equipment that is replaced at conversion point may be moved to a location that has a 25Hz failure. All rolling stock that connects to the CAT is now constructed so it can operate on either 12.5Kv 25Hz (11Kv nominal) or 25Kv - 60 Hz power.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
The dedicated railroad turbines currently feeding the NEC can produce 60 Hz power but only through a converter and they lose about 10kw in doing so. The obvious advantages of conversion to 60 Hz is easy use of local power and the ability to knock down those power lines from the hydroelectric sams.
Speaking of the hydroelectric power transmission lines between the dam and the NEC, the ARRA proposal has a project for replacing those transmission lines specifically. Conversion to 60 Hz is even more outside the scope of ARRA, especially the 25 Hz signal power converter project to power 60 Hz signals using 25 Hz power.
aegrotatio Speaking of the hydroelectric power transmission lines between the dam and the NEC, the ARRA proposal has a project for replacing those transmission lines specifically. Conversion to 60 Hz is even more outside the scope of ARRA, especially the 25 Hz signal power converter project to power 60 Hz signals using 25 Hz power.
IMHO you have it mixed up. When the NH signals were first upgraded Amtrak had local utilities supplying all signals and grade crossing signals (F-40s operating) and removed all NH pole lines. As the CAT transmission lines were installed a transformer was added to each track's power transmission line to provide 240V 60 Hz power to the signal systems so each power cable could provide power. After the CAT and power cables were energized the local utility connections were terminated. The ARRA has now provided for those connections to be reinstated along with an expanded automatic switching system to power the signals. So now any signal can get power from track "A" if it fails then track "B" and if that failed then from local utility. If there is a track "C" it also has a transformer and the switching hardware. Back then when I asked a road foreman why AMTRAK didn't use local utilities as a further back-up got answer "that the way some one wanted to do it" (shortsighted as we now see). Now new hardware has to be bought to use the third (or more) back up source.
Now the PRR system. -- PRR signal power comes from each 25Hz substation by way of a frequency multiplier (new) or a motor generator set (original PRR and maybe CR) that can run at 1500 RPM or 750RPM producing 100Hz power to the signal power lines. The ARRA is providing money to have local 240V 60Hz utility power to each signal bungalow. A two way frequency converter is installed to give 100Hz power to the signal from the 60 Hz power when the 100Hz has failed . Any bungalow that has new 60Hz signal hardware will have the converter reversed using the 100Hz converted to 60 Hz for the signal bungalow. Sounds to me as a first step to converting the NEC to 25Kv 60Hz
Note: made a couple typos and have corrected.
Okay, I was only talking about the system south of New York City. The ARRA project appeared to be designed to accomodate both old and new signals using both 60 Hz utility and 25 Hz catenary power.
Still your extra info is very interesting.
aegrotatio The ARRA project appeared to be designed to accomodate both old and new signals using both 60 Hz utility and 25 Hz catenary power.
The ARRA project appeared to be designed to accomodate both old and new signals using both 60 Hz utility and 25 Hz catenary power.
You need to kick me. I did not explain that at some (not sure about each) 25Hz substation there are frequency multipliers or motor generator sets that produce the 100Hz power. This is then fed onto separate 6600V (NOW sure about that value also probably 1 phase) power lines that are usually attached to the 138Kv power poles. This 100Hz is then fed to transformers at each signal location to power the signal bungalow. Hope this clarifies for all of you.
Yes! It sure does. The 4400V is such a weird number I don't blame you.
aegrotatioThe 4400V is such a weird number I don't blame you.
This is pure speculation but the original high tension lines were 66/132 KV. By steping down voltages 66Kv is a multiple of the original 11Kv CAT. A further step down makes 6600 V a multiple which at the bungalows gives a 110/220V signal power. The 6600V may have been necessary to push the power to a half - way point between substations although I suspect that provisions were in place to push to next substation if its 6600V power supply failed.
One additional point --- around the WW2 era the primary voltage of the transmission lines were pushed up to 69/138Kv without changing any of the other transformers so they now had 11.5Kv CAT and 4600V signal primary and 115/230V to the signal bungalows. Sound familar??.
Just so you know in case there is a voltage drop on the 138KKv transmission lines all equipment is built to run under voltages as low as 9500V (?) The CAT voltage 11Kv is specified to meet for all full performance of all rolling stock. However they can all handle 12.8 Kv (? can't remember) and most equipment utilizing both 25 Hz and 60Hz. Example the new MN cars will take the 11.5/ 12.0Kv Kv 25 Hz, and the 12.5/25Kv 60 Hz by utilizing an automatic transformer center tap switch.
Have edited the voltage values
blue streak 1 This is pure speculation but the original high tension lines were 66/132 KV. By steping down voltages 66Kv is a multiple of the original 11Kv CAT. A further step down makes 4600 V a multiple which at the bungalows gives a 110/220V signal power. The 4600V may have been necessary to push the power to a half - way point between substations although I suspect that provisions were in place to push to next substation if its 4600V power supply failed.
This is pure speculation but the original high tension lines were 66/132 KV. By steping down voltages 66Kv is a multiple of the original 11Kv CAT. A further step down makes 4600 V a multiple which at the bungalows gives a 110/220V signal power. The 4600V may have been necessary to push the power to a half - way point between substations although I suspect that provisions were in place to push to next substation if its 4600V power supply failed.
OOPS!! PDN helped set me straight on these values. Signal feeders were actually originally 6600V a 10:1 step down ratio and with the step up of transmission lines to the 69/138Kv the signal feeders went to 6900V. using the same 30:1 step down ratio. Still would get 110/220V stepped down then 115/230V at the new voltages. Saved a lot of equipment changes. I'm going to correct all my posts.
Our community is FREE to join. To participate you must either login or register for an account.