|transformer = traction|
|Using this tag is discouraged, use transformer=main instead.|
|Used on these elements|
|Tools for this tag|
Despite special transformers architectures can be used to feed transportation traction systems, they're not specific to traction.
We can find similar devices for industry or research use cases.
As to properly describe such systems, see substation=traction to tag a substation hosting power supplies for transportation.
Those transformers are actually best described with transformer=main and possibly windings:configuration=* if you're knowledgeable about their internal parts.