DMG DMU 50 Retroftiing(?) help

Where I live (Norway)  its quite common to have 3x220v without any neutral, I think its called 'IT'. You are quite right that most industrial equipment are 380V, and our industrial buildings often have transitioned to that system (its called 'TN' here). My garage, however does not have it. 

If norwegien terminology is anywhere nere european standards IT stands for "isolated" and "terra", doesn't really say anything about voltages. Star point of source transformer is isolated, whereas in a "TN" net it is grounded. Around here you see IT type typically in hospitals or datacenters because it can safely tolerate single faults from "hot" to earth.

As always, measure once, cute twice.
 

Norway, i do recall a documentary where it mentions trains having to switch to Sweden's power, so something is different there, just cant recall what.

Completely off topic, but austria, germany, norway and sweden signed this de.wikisource.org/wiki/%C3%9Cbereinkomme...er_Zugf%C3%B6rderung in 1912, setting a common standard of 15kV alternating current with 16 2/3 Hz. In austria, trains are fed by their own power generating stations and a separate power grid.

 

something is different there, just cant recall what.

I have no idea but according to this you two seem to have something in common:
www.worldstandards.eu/electricity/three-phase-electric-power/

Where I live (Norway)  its quite common to have 3x220v without any neutral

So if you have 3x220V and your spindle takes 3x220V (if the posted plate is correct) then a 3x220 VFD would work, no? Probably best to ask a local electrician in any case.

So just out of curiosity, this would mean that your regular domestic wall socket would actually be 2-phase 220V ?

Yes indeed. L and N is connected between two phases in the distrubution box. The wires are still brown and blue, and any switch or socket is still marked L &N though.
It kinda threw me for a loop when i first moved here from Sweden. It never crossed my mind that there were different ways of delivering household electricity. I get three phases from the supplier in to my house. In addition there is a PE pole staked in to the ground outside, and a PE cable that run in the my distrubution box. On older houses it is common to still the the PE line connected to the copper water pipe.

Just to add to the confusion, here are some more pictures.

Wires coming in to my house. 3 phase, no neutral.
 

Installation certificate in my distribution box:
 

A 3phase connector:
   
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