Because not everyone on my friends list reads Anachrotech...

[ffutures]

...and some of you are railway fans

anachrotech just posted a link to the article below, about hybrid electric / steam railways in Switzerland post WW2. Yes, they were steam engines that heated the water electrically. Totally weird, but the explanation more or less makes sense.

http://www.dself.dsl.pipex.com/MUSEUM/LOCOLOCO/swisselec/swisselc.htm

Comments

[nojay.livejournal.com]

It seems an obvious thing to do, really, given the circumstances (shortage of coal, lots of hydroelectricity).

As for the "odd" supply frequency of 16.6Hz mentioned in the article, that's understandable with a bit of thought. Electric traction requires slow motors with a lot of torque and in the 1930s/40s electric motor control was primitive -- no frequency modulation available. At 16.6Hz a single-phase motor will turn at 1000rpm (it has to be single-phase as there's only one catenary wire feeding the loco). This gives more torque than a 3000rpm motor (50Hz) plus the gearbox to the drive wheels can be smaller and more reliable. As for the transformers being bigger, for a locomotive a high all-up weight is a necessity to provide traction for steel wheels on a steel rail.

[ffutures.livejournal.com]

It does make sense, it's just not (to me at least) the first thing I'd think of in this situation. If you go back to the main page of that site there's a link to a steam-generator electric train, doing things precisely the opposite way.