Twelve-pulse diode rectifier with reduced input current harmonics

Diode rectifiers have been widely used for an AC-DC converter. One of their problems is that they include large harmonic components in its input current. A 12-pulse diode rectifier is useful for reducing them, but it still includes the (12 m/spl mnplus/1)/sup th/ (m: integer) current harmonics in its input. In order to further reduce the input current harmonics a single-phase square wave voltage supply is combined to a 12-pulse diode rectifier as an auxiliary supply. Theoretical analysis of the combined twelve-pulse diode rectifier is presented, and reduction in the harmonics and improvement on the displacement power factor are verified by simulation and experimental results.