Rotary converter

A rotary converter is a type of electrical machine which acts as a mechanical rectifier, inverter or frequency converter.

Rotary converters 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.^[1]