AMTRAK announced today that they are starting 165 mph testing tonight on the New Brunswick - Trenton segment of the NEC using an ACCELA train set. (22.9 miles ) There is no indication if these tests will be one way or both ways and which tracks will be involved ?
Later this week and next week tests will be done Perryville, Md – Wilmington, De (21.3 MILES) ; Then Westerly - Cranston RI. ( 29.2 miles ) & S. Attleboro - Readvilles Ma ( 27.8 miles ).
In my opinion I suspect that the 2 segments south of NYP are being done now when the PRR style CAT will be at a neutral tension due to lower air temperatures. The tests north of NYP will give a comparsion of CAT interactions with the PRR style vs. the constant tension type.
Not considering the acceleration deceleration lengths — North of NYP increasing the speeds from 150 - 160 will only save approximately ~~ 40 seconds each section. If the tests result in the desired 160 south of NYP the time savings would be 2;25 each section at present 125 MPH and 1;30 at 135 MPH when able. ( extreme weather temps usually limits speeds to 125 on the south of NYP segments.
If you look at the comments you will find a video of the Acela going through Princeton Junction Station. The last part shows the Acela running at 165 miles per hour.
An couple of notes. The following article mentions it was a 9 car train. If that means 9 passenger cars + 2 power cars this will be the first known run of a nine car train. This test will certify ACELA for the additional cars now on order that will add 2 cars to each train. I imagine AMTRAK borrowed one coach from another set and added their train geometry car into the consist. anyone know for sure ? since I now have viewed the video and do not believe that they operated a 9 car train ?? but maybe tonight ??
After watching the video I could only count 7 cars. Is it possible that AMTRAK will be conducting more test with the longer train ? Anyone have more difinite information ?
7 cars plus 2 locomotives…that’s 9 units. Depending on who wrote the copy, they saw the 9 units and thought they were all cars. I don’t think they will add two cars which would be more than a normal Acela set.
That arcing certainly was one of many test items. I believe that the arcing happens because the rear PAN cannot keep contact with the PRR variable tension CAT. It is possible that the front PAN sets up a harmonic on the contact wire that causes the rear PAN to loose contact. It may be that the longer trains of the planned 9 cars would not have arcing. It really will take some tests?? That arcing may prevent normal operation of the ACELAs above 140 ?? In the good old PRR / CR days some arcing was observed. The arcing was so pronounced that it could cause some static on aircraft radio receivers that soounded like a welder. Have no idea how much will be allowed or tolerated. Just one more reason to get constant tension CAT installed.
The tests between Perryville - Wilmington will give results on CAT built in a different year that was slightly different design. Then the tests north of New Haven will give results on new constant tension cat.
It seems to me that this arcing will have to be addressed. It will erode and add unevenness to both the wire conducting the electricity and the pantograph where electricity is picked up. No doubt constant tensioning will reduce it but will it be eliminated? I don’t know. I also don’t know how it is handled in places that now run high speed trains, if they use diesel engines or similar power or if they use electric trains and have found a way to deal with it.
But you are absolutely right abut needing a constant tension catenary which Amtrak plans to do.
I found a fairly straightforward explanation of the system used in the Shinkansen line in Japan. It also has a measuring device to measure wear so it appears that even at best there is degradation over time and the system must be maintained. But nothing is perfect in this world.
The problem with arcing is that a good chunk of the voltage drop in the circuit is across the arc, so you aren’t getting full power to the propulsion system.
Take a look at the video of the TGV record run. There is some nice video of the pan and catenary.
So here is the really critical question. When will Amtrak bake 165 mph into the schedule? I need to get a ticket and take a ride.
This is great! No need to go to Europe or Japan for a high speed choo choo ride. I don’t know about most people, but I could not tell the difference between 165 mph and 187 mph without a speed indicator.
I think it will be a while before Amtrak schedules runs at 160 miles an hour, Streak.
The arcing is actually sputtering along the line and is continuous. It is all about the physical properties of the catenary system. Sputter occurs when there is an insulator between two parts of an electrical connection and the insulator breaks down. In this case the insulator is air. It is present because as the pantograph contact runs under the catenary wire the wire will oscillate and bounce on and off the catenary. It is especially pronounced in warm weather when the catenary wires expand and are a little loose. When the current catenary is replaced with a tensioned catenary the effects of temperature on it will be much reduced and it should work a lot better. However, that will take a while.
I think you pointed out that tests north of New Haven where a tensioned catenary is in place should be less likely to cause sputter along the wire.
Finally, Amtrak has the money to upgrade the catenary and from what I read is planning to do so.
(from the end of the video) Vive la France! Vive la France!
I was looking at the three dudes in the cab to get some sense of the ride quality – didn’t seem that bad. The constant arc at the pan pickup shoe makes this a showstopper for regular service.
I guess my question is how they geared the motor. You need to develop considerable power over the 0-350 MPH speed range with one gear ratio? I don’t think any race car does this without gear shifts. Are they using an AC traction motor – I am thinking that a DC motor would have bird-nested a couple hundred km/hr ago.