Ringing choke converter

The next question is, is the efficiency being lost in the switch If so, there could be many reasons for that. A switch could be lossy simply because its drive is inadequate. Early self-oscillating converters (ringing choke oscillators) were extremely lossy because the drive would slowly droop to the point where it just couldn t sustain itself and then the switch would turn OFF. Modern self-oscillating converters have improved tremendously on this, and you can even find full-fledged multi-output PC power supplies that don t have a single... 

A sulphuric acid piant can run efficiently with elemental sulphur as a raw material (having very low ash and organic content), but this is not always available at many locations. The plants located at such places depend on imported sulphur. They can use sulphur with a more ash content (which can be cheaper and available locally in certain countries) with prefiltration of sulphur and special ring-type catalysts in converter passes which are less prone to getting choked due to ash. 

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