WordNet
n. electrical converter consisting of a synchronous machine that converts alternating to direct current or vice versa [syn: synchronous converter, rotary]
Wikipedia
A rotary converter is a type of electrical machine which acts as a mechanical rectifier, inverter or frequency converter.
Rotary conveerters were used to convert alternating current (AC) to direct current (DC), or DC to AC power, before the advent of chemical or solid state power rectification and inverting. They were commonly used to provide DC power for commercial, industrial and railway electrification from an AC power source.
Rotary converters are still used as frequency converters.
Usage examples of "rotary converter".
The first housed a power plant, with a small rotary converter humming silently beside a bank of transformers, and a stand-by unit waiting.
A small concave palladium mirror, at the base of it, faced a similar mirror mounted on something not quite like a small rotary converter.