[Laci1959]

http://kepkezelo.com/images/wea2apihsfvo0eijqwl0.png
Hello
Compared to INVALID it keeps it quite accurate. See picture.
Regards Laci 1959

[Csantucci]

Laci1959, on 16 July 2021 - 01:25 PM, said:

Hello.
I found it in a Czech vehicle. It was a little weird for me too. The speed controller has no fixed positions, it can be controlled continuously. What is the solution for a continuously controllable controller? Maybe ORTSMaxTractiveForceCurves?

This is the setting of a KISS motor train, in which the "Throttle" can also be controlled continuously. Anyway, the same phenomenon is the same.
Regards Laci 1959

Laci,
I tried to use your above setting, with values divided by two (because the E464 has a max force of 200 kN) and with a load of 5 carriages, and the behaviour is satisfying.

[Laci1959]

http://kepkezelo.com/images/ril385g7hjyvkqjpd5r8.png
Hello.
This is a characteristic of a FLIRT multiple unit. Official publication for the training of engine drivers. The curve is straight in the first quarter of the speed range. There is only one curve for "all controller positions". There are no fixed jobs like ORTSTractionCharacteristics requires. I think the programmers have slipped over this.
Regards Laci 1959

PS.
So where could the mistake be? Should I make a video of it or have you seen the phenomenon?

[Laci1959]

Weter, on 16 July 2021 - 11:53 PM, said:

Wow, M(62)ашка! 3D cab?
I see very interesting table form!
I thought, the statements must be in pairs only, but here, everything looks very clear.

You must be in pairs when using ORTSMaxTractiveForceCurves. When using ORTSTractionCharacteristics in a table.
The table was made with Excell. I use the Save As menu item, where I select Formatted Text (space separated). The file is given the prn extension. I open it with Notepad and copy the spreadsheet and then paste it into the eng file.
I hope you understand.

[Weter]

Well, that's great, that ORTS accepts such form of data - this way, it would be very simple - to refer the real tractive characteristics for modeled locomotives.
And thank you, Laci for advice, how to make that easily.
As for Flirt.
I suppose, this is a modern stock with contact-less semiconductor (most likely, IGBT) -based, smooth variable traction control, handled by computer.
This way, driver only refers the desired result, but not controls motors directly.
It means, at factory, the optimal, averaged characteristics for traction curves was pre-programmed to PLC of the engine unit. (Programmable-logic computer)
So:
The flat part is intended for avoiding wheelslip and motors overload by current, at the moment of start or creep at minimal speeds.
Single curve is shown, maybe, because there is notchless algorithm here, instead of contractor-based controllers, where every notch had its own curve. Instead, at every moment, the most optimal voltage, current and frequency are computed for fitting driver's (or cruise-control) reference, and compensation variables are applied, taking in account the feedback signals from current and speed sensors.

[Weter]

Please, note one more thing: the constant-formation passenger trains is more easy task for pre-programming an algorithm of traction controlling, than freight electro haulers, because that first ones suffer not so significant weight fluctuation, compared with unpredictable and unmeasurable, wariable in wide ranges, weights of freight trains.

[Laci1959]

Quote

Single curve is shown, maybe, because there is notchless algorithm here, instead of contractor-based controllers, where every notch had its own curve. Instead, at every moment, the most optimal voltage, current and frequency are computed for fitting driver's (or cruise-control) reference, and compensation variables are applied, taking in account the feedback signals from current and speed sensors.
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Yes exactly. I feel like this was forgotten when the program was made.
There are no such issues with the 2019 Pre Alpha version.

[Laci1959]

Weter, on 17 July 2021 - 02:01 AM, said:

Pre Alfa version of what?

Jindrich knows what I mean. I really liked it then, especially the stopped diesel engine and the real-life battery switch.
" Pre-Alfa 6 verze ORTS s implementací ARR systému.
------------------------------------------------- "

[Laci1959]

Weter, on 17 July 2021 - 02:21 AM, said:

???
Magyar private version of OpenRails?

118 / 5000
Fordítási találatok
Made by Jindrich. Not so private, a friend of mine came across it and gave me the link. Sorry, I didn't save the link.

[Weter]

Again to the graph: we see the only part, typical for bottom of automatic (natural) traction characteristic, which, in whole, looks like a hyperbola.
This is, likely, because this is intended for passenger train, where significant traction force at start is not needed, thanking train's moderate weight, compared to power of its motors.
And the initial part of graph is turned flat automatically (which actually means real-time continuous automatic tuning of motor's feeding characteristics by PLC), while in case of manual control, the driver have to obey current limitations by himself, watching the reading of load meter. Though diesel-generator units are able to protect themselves from overloads.
Speaking more verbose, in past, there was a number of voltage sets, provided to motors by controller, so every voltage produced its own traction characteristic.
This voltages were given by different transformer's setting, different diesel rotation speed setting or different motors arrangement plus additional resistors in variable combinations usage.
With invention of controllable rectifiers, the smooth regulation (the more modern of which, as far as I know, is vector control algorithm), allows to have one synthesized characteristic, similar to natural as far as it needed, for full speed range, while all compensations are performed by PLC automatically.
This allows the engagement of auto-driving and cruise-control to be more efficient, flexible and universal.