Railway Preservation News
https://www.rypn.org/forums/

The Future of American 25 Hz Traction
https://www.rypn.org/forums/viewtopic.php?f=1&t=39029		 Page 1 of 3
Author:  Cameron Wolk [ Sat Jan 23, 2016 8:13 pm ]
Post subject:  The Future of American 25 Hz Traction
As time goes by and the future ever so gets closer I'm curious to speculate what will ever happen to Amtrak and Septa's 25 Hz catenary system. It has so far withstood the test of time operating for more years than any engineer could ever have predicted it would and still provides reliable power for the Northeast Corridor. In my mind I feel it's honestly cheaper to maintain and operate than say purchase 60 Hz power from a company such as ConEdison.

If there's ever a failure or break in inter-corporate relations at least Amtrak would have the ability to address the problem themselves than say wait for a response from the host supplier. Perhaps instead of maintaining inefficient rotary stations it would be more business conventional for the two parties to construct a joint power plant capable of meeting today's operating demands. The ideas are endless but time isn't very much so lets discuss while there is still fire in the woodpile,

Cameron
Author:  robertmacdowell [ Mon Jan 25, 2016 3:44 am ]
Post subject:  Re: The Future of American 25 Hz Traction
Silicon switching is having a double effect on railway electrifications. On one hand, the equipment stops caring whether the incoming AC is 10 Hz, 25, 50, 60 or DC. On the other, it's easier to manufacture 25Hz from arbitrary power inputs.

Mind you, doing so is mandatory. Even if trolley frequency is 60Hz, railway power wants single-phase. The power company can't supply that in any appreciable quantity, because that is an imbalance on their inherently 3-phase system. So you need to something enormous to ensure all 3 phases are loaded equally by your single-phase railroad. These days, the figurative path of least resistance is to take all 3 phases, use GTO thyristors to slice dice and julienne them into a DC intermediate stage, then chop whatever output waveform you please.

That's not that big a deal. After all, plain diodes have gone out of fashion - they add a volt or two of voltage drop - more if they're stacked in series to handle high voltages. Instead, for simple rectification, they use GTO thyristors, which do not have nearly the voltage drop. While they are 2-way devices and can't diode worth a darn, they can be commanded to turn on or off at any instant... so guess what - a microcontroller turns them on when current is forward. Emulating a diode in software! So, the hardware is basically there, and it's not much of a leap to chop any signal they might want.

There's a lot of other stuff with power distribution and phasing. After all, electricity only moves at the speed of light. New Haven and Washington can supply power which will arrive in Philadelphia in perfect phase, but if the load lightens up in Philly and momentarily peaks in New Haven, the Washington power is arriving "late to the party" and about 35 degrees out of phase if my math is right. That's a big damn problem. Obviously the faster the frequency, the more of a problem this is, if our power grid was 4000 Hz, we'd never get anything in sync! Or vice versa - if running 25Hz, the Philly power is just as late, but that's only 15 degrees.

Of course, the lower the frequency, the larger the iron cores in your transformers. That matters if you're trying to make lightweight high speed trains. But it doesn't matter if you're no longer using transformers.
Author:  Benjamin J True [ Mon Jan 25, 2016 11:02 am ]
Post subject:  Re: The Future of American 25 Hz Traction
So for those of us who don't know anything electric traction under a wire...

Where in the world are they getting 25 hz at now? Don't tell me there a 100 year old PRR steam power plant out there with an 0-6-0 in a barn in the corner of the lot......
Author:  JimBoylan [ Mon Jan 25, 2016 12:43 pm ]
Post subject:  Re: The Future of American 25 Hz Traction
Some of the 25 cycle supply comes from generators at the Safe Harbor (Pennsylvania) Dam. There are also frequency changers near Port Richmond (Philadelphia, Pennsylvania), Edison (New Jersey) and elsewhere that convert 60 cycle electricity. Some of those are giant rotary machines that, because of their inertia, can survive minor variations in their supply that break the modern electronic versions.
Author:  Cameron Wolk [ Sun Feb 14, 2016 12:46 pm ]
Post subject:  Re: The Future of American 25 Hz Traction
Speaking of GG1s and other former Pennsy electrics may I ask how is that P5 prototype doing in St louis these days? Out of all this chatter and discussion have we forgotten about probably the most intact PRR unit to be restored to operation. A past talk I've had with their curator indicates the unit still has the vast majority of its components and could technically run given they had 25Hz catenary to run it on. I believe out of all our options we should consider at the very least a probable restoration for the #4700. Perhaps a joint partnership could be constructed with Amtrak, Septa or NJT to support such a project, maybe they'd show interest.

Cameron
Author:  EDM [ Sun Feb 14, 2016 3:12 pm ]
Post subject:  Re: The Future of American 25 Hz Traction
Any sort of restoration of a G motor or P5 would require cubic yards of money, which neither NJT, SEPTA or Amtrak have right now, or will be likely to ever have again. Ant the private sector isn't any richer, either.

Have you driven on any roads in New Jersey lately? (Assuming you even drive-) Or ridden Amtrak, NJT or SEPTA? Any 'spare' money that any of the transportation agencies have, rail or highway, should be going into infrastructure maintenance and improvement, not some wild-eyed 'foamer fantasy'.
Author:  Cameron Wolk [ Sun Feb 14, 2016 5:34 pm ]
Post subject:  Re: The Future of American 25 Hz Traction
EDM wrote:
Any sort of restoration of a G motor or P5 would require cubic yards of money, which neither NJT, SEPTA or Amtrak have right now, or will be likely to ever have again. Ant the private sector isn't any richer, either.

Have you driven on any roads in New Jersey lately? (Assuming you even drive-) Or ridden Amtrak, NJT or SEPTA? Any 'spare' money that any of the transportation agencies have, rail or highway, should be going into infrastructure maintenance and improvement, not some wild-eyed 'foamer fantasy'.


Going back by two years I had a good conversation with the current C.O.O. (chief operating officer) of Amtrak and funny enough we talked about the same idea. What he basically described to me would be that as long as such a project would benefit the company's PR he'd green light an operational GG1 by all means. Being honest with you Eliott there's nothing wrong with the current state of the NEC. The only reason why there is so much uproar is because my generation will simply complain over anything they don't like. That's why I suggested the #4700 in the first place, it'll be much less expensive to restore and will hold up better cosmetically (no frame cracks) than a G.

Cameron
Author:  EDM [ Sun Feb 14, 2016 9:13 pm ]
Post subject:  Re: The Future of American 25 Hz Traction
Nothing wrong with the NEC? Portal bridge and the Hudson River Tunnels, and that's just in NJ. Enough said-
Author:  Overmod [ Sun Feb 14, 2016 9:18 pm ]
Post subject:  Re: The Future of American 25 Hz Traction
Better be careful with that 'no frame cracks' until you 'flux it -- Staufer documented how cracked the P5s got near the end, including the creative use of thick PC black as a kind of Beaumont Egg...

Aside from which the vehicle dynamics of a P5 at speed are just awful, and known to be so before the GG1 development was undertaken. And frankly, compared to a GG1 only the Pennsy fans are going to care ... 4700 is just a plain old box to most people, snazzy handrails or no, whereas the GG1 is a Streamline Moderne masterpiece (like the T1). There is also something just ... wrong ... about 4700 pulling almost anything modern in the Corridor, whereas the Gs have a history not only of pulling Amfleet, but doing so faster than any contemporaries. (Note I say as little as I can about getting them stopped afterwards in a way that allows them going afterwards...)

Yes, I'd like to see 4700 restored, but no, I can't imagine the fun involved in actually running it where it would make any sense, and no, I'd rather see that money spent on something with a better sort of payback.
Author:  Trainlawyer [ Mon Feb 15, 2016 12:42 am ]
Post subject:  Re: The Future of American 25 Hz Traction
Cameron Wolk wrote:
EDM wrote:
Any sort of restoration of a G motor or P5 would require cubic yards of money, which neither NJT, SEPTA or Amtrak have right now, or will be likely to ever have again. Ant the private sector isn't any richer, either.

Have you driven on any roads in New Jersey lately? (Assuming you even drive-) Or ridden Amtrak, NJT or SEPTA? Any 'spare' money that any of the transportation agencies have, rail or highway, should be going into infrastructure maintenance and improvement, not some wild-eyed 'foamer fantasy'.


Going back by two years I had a good conversation with the current C.O.O. (chief operating officer) of Amtrak and funny enough we talked about the same idea. What he basically described to me would be that as long as such a project would benefit the company's PR he'd green light an operational GG1 by all means. Being honest with you Eliott there's nothing wrong with the current state of the NEC. The only reason why there is so much uproar is because my generation will simply complain over anything they don't like. That's why I suggested the #4700 in the first place, it'll be much less expensive to restore and will hold up better cosmetically (no frame cracks) than a G.

Cameron

Cameron,

First - A crack in the frame is not a cosmetic issue. It is a significant structural issue which will take the engine out of service. The many gallons of Gloss Black paint which were applied to cracked frames were not intended to make them look pretty but to hide the cracks from the Federal Inspectors.

Second - I do not know if you ride the Corridor on a regular basis or if you yet have the skill set or the knowledge base to really know what you are looking at. There is plenty wrong with NEC, not the the least of which is that there just is not enough of it and many of the components are overworked regularly to the point of failure. Its not just your generation's complaints. It is Brother Moxley's generation and my generation also. Brother Moxley mentioned a few of the better known choke points where things go wrong several times a week. I could point to several more. It is a credit to Amtrak's people that things run as well as they do.

Third - None of those agencies you mentioned are profit making corporations. Of course they will pay lip service about positive PR but I do not see them offering cash. If you go on their website and check you will see that Amtrak's charitable donation program is essentially limited to providing free transportation on regularly scheduled trains for qualified charities.

Fourth - The GG1 was designed to overcome weaknesses in the P-5 as was the R-1. I agree that the P-5 would be nice to repatriate and restore but I also tried to save an L-6 for operation and it was a very hard row to hoe even then.

This is actually a very interesting question - the core of which is the future of a particular form of electric transmission. Do some studying on the history of railroad electrification. Middleton's When Steam railroads Electrified is a good start. I can suggest some more technical books if you like. Then ask some questions and we can resume the conversation.

GME
Edited to correct a long overlooked spelling error
Author:  Cameron Wolk [ Mon Feb 15, 2016 2:06 am ]
Post subject:  Re: The Future of American 25 Hz Traction
The PRR's 25 Hz transmission is designated as a national engineering landmark meaning that the system itself cannot be radically altered or changed to accommodate a new voltage. In my lifetime and probably the lives of many others the 25 Hz catenary will remain untouched given that it can be supported for future decades to come. I strongly believe in its own uniqueness it can withstand the folds of times if it's maintained and operated by the right people with the right skills. Maybe looking back at the New Haven or the Virginian we can learn a lesson or two about special operating transmissions. Cos Cob from 1907 to 1987 despite all odds was able to supply efficient power to the NEC without breakdown and even still operated with perfection. With that said going to my original comment perhaps it's time for Amtrak to take on its own homemade project of building a plant capable of supporting today's demands. It would eliminate the need for selective rotary stations and could support the grid route-wide without disruption. I can only imagine the price tag for such an undertaking but in the end the payback should meet its cost equally.

Cameron
Author:  EDM [ Mon Feb 15, 2016 7:52 am ]
Post subject:  Re: The Future of American 25 Hz Traction
I would like to see some written proof that the old PRR 25 cycle transmission system is a national engineering landmark and can't be changed. The NH electrification was much older then the PRR's (was a prototype, in fact) and has had it's voltage and I believe frequency changed.

I have also read, many sources in fact, that the NH generating plant at Cos Cob was on it's last legs, and that NH management wanted to reduce it's load by running all but the MU trains behind diesels. FL-9s were to be used for long distance passenger, and diesels were to operate freight trains over Hell Gate onto Long Island.

COL Edwards has made an excellent suggestion with the Middleton books. I also have first hand information, from a manager that was involved with the GG-1s on lease by PC and later Conrail to NJT and AMTK, that they were spending about $100,000.00 per unit just fixing and re-fixing those cracks.
I'd be very surprised if the current AMTK COO you mention wasn't aware of that situation.
Author:  Alexander D. Mitchell IV [ Mon Feb 15, 2016 11:26 am ]
Post subject:  Re: The Future of American 25 Hz Traction
Cameron Wolk wrote:
The PRR's 25 Hz transmission is designated as a national engineering landmark meaning that the system itself cannot be radically altered or changed to accommodate a new voltage.

First, like Brother EDM I cannot find any listing of the PRR 25Hz electrification as a "national engineering landmark," either Civil or Mechanical.

https://en.wikipedia.org/wiki/List_of_H ... _Landmarks

https://en.wikipedia.org/wiki/List_of_H ... _Landmarks

PRR GG1 4800 is listed on the latter list, incidentally.

Second, Mr. Wolk conveys the all-too-typical ignorance of the National Historic Landmark and/or National Register of Historic Places program, and furthers it by confusing it with the entirely separate, unaffiliated National Civil/Mechanical Engineering Landmark program, which is overseen by the American Society of Civil Engineers instead of the National Park Service and Library of Congress:
https://www.asme.org/about-asme/enginee ... ks-program

The ASME even specifically states in its FAQs:
Quote:
Alteration, Removal, or Destruction of Landmark

Does ASME landmark status mean that an artifact or collection cannot be altered, removed, or destroyed?

No. The ASME designation does not have the force of law that a National Register designation has. Therefore, an owner is free to alter or demolish the landmark. ASME hopes, however, that this recognition will encourage the preservation of these examples of our industrial heritage. If a landmark is destroyed or undergoes major alterations, its plaque must be returned to ASME.

Going down the lists, I found any number of Engineering Landmarks that have been demolished, removed, or altered substantially, in many cases for the better (the CB&Q Roundhouse in Aurora, Illinois, now a huge brewpub and restaurant complex, for example). A few others are too impossibly vague to be "protected"--all geared steam locomotives, for example, or the Jeep Model MB.

Even the imprimatur of National Historic Landmark or National Register protection doesn't convey anywhere near the absolute protection that too many amateur historians would like to fantasize. We've had this discussion before, and I won't rehash it here.
Author:  Roger Mitchell [ Mon Feb 15, 2016 11:14 pm ]
Post subject:  Re: The Future of American 25 Hz Traction
The European system uses 25KV at 16 and 2/3 Hertz single phase power. The lower frequency allowed for using universal series wound motors similar to the series wound DC traction motors used on DC systems but with laminated field cores to permit operaion on AC current. Today it doesn't really matter with modern solid state devices. Even thyristors are old hat. Today IGBT's have largely replaced them. IGBT stands for Insulated Gate Bipolar Transistors. IGBT's can switch very high voltages at enormous currents with very little voltage drop.
Author:  wilkinsd [ Tue Feb 16, 2016 11:47 am ]
Post subject:  Re: The Future of American 25 Hz Traction
The big problem here is that the original poster, besides being all over the map, simply does not "get it."

PRR utilized commercially purchased power because in the long run, it was a more cost-effective alternative than building and maintaining your own power generating infrastructure. The New Haven, by being the pioneer in the field of high voltage AC traction in the U.S., learned this lesson the hard way. The Cos Cob plant was on its last legs for many years prior to it being removed from service and torn down. To say it worked "flawlessly" ignores the fact that the New Haven and its successors never had the money to invest in improving and modernizing it.

By the time the PRR got serious about electrification of its Washington to New York mainline, that lesson was readily apparent. It is cheaper to purchase and convert commercial AC power, than generate your own. Thereby, you pass along the costs of maintenance and upkeep of power generation to the power company, and the railroad can be in the business of being a railroad.

In fact, when looking at the length and breadth of American mainline electrification, making your own power was in the minority. N&W and the Virginian had their own reasons, mainly due to the remote location of their operations. Even the Milwaukee Road's electrification used commercially purchased power.

When the Muskingam Electric operation debuted in the 1960s, it promised to usher in a new era of high voltage AC traction, where there was no need to convert the frequency. Power could be provided to the contact wire at commercial voltage with no conversion. At the time, John W. Barriger was a proponent of railroads leasing their right of ways for high voltage transmission lines, provided the power companies provided a contact wire at 50k, 75k, or 100k volts, to power the locomotives. Power consumption would be monitored via on-locomotive meters.

So what does this all mean? Amtrak isn't going to build a power plant it doesn't need. Why would it? Why go through all of the regulatory hoopla to build a plant when monies could be better spent on other infrastructure upkeep. Leave the power generation to the power companies. No misstatement of facts by anyone, including Mr. Wolk can change that.
Page 1 of 3 All times are UTC - 5 hours [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/