My first job was as a test technician in a transformer factory I remember we had a 400 cycle supply from a motor generator big old noisy thing it was. Also a 150 cycle supply derived from 3 transformers this gave a max if 500 volts out i never figured out how it worked how do you get that from normal 3 phase 50 cycle mains??
probably a cycloconvertor based on SCR switches, assuming 1970 or so.
Still used for some countries railway traction power at 16.6Hz (50Hz/3) to 50Hz conversion. Waveform quality is not great without extra L-C filtering, probably not an issue for a transformer maker to rustle up some extra coils !!
thyristors fire off to make the outgoing waveform by slicing up the incoming one into 3rds, or is it 9ths ..
probably a cycloconvertor based on SCR switches, assuming 1970 or so.
Still used for some countries railway traction power at 16.6Hz (50Hz/3) to 50Hz conversion. Waveform quality is not great without extra L-C filtering, probably not an issue for a transformer maker to rustle up some extra coils !!
thyristors fire off to make the outgoing waveform by slicing up the incoming one into 3rds, or is it 9ths ..
