THREE-PHASE AC-DC CONVERTE WITH HIGH-FREQUENCY INSULATION BY SINGLE STAGE

摘要

The innovation presents an unidirectional transference of power from a three-phase current for the load in insulated way by means of an three-phase PWM Buck rectifier connected to forward/flyback transformer, where these two structures compose an AC-DC converter with a single stage of operation. The tree-phase PWM Buck rectifier provides the rectified modulated voltage in high frequency for the primary wound (Np) of the transformer. The secondary wound (Ns)1 or forward, is responsible for bigger part of the power transferred to the load and tertiary wound (No), or flyback demagnetizes the nucleus of the transformer regenerating this energy to the load. The modulation for width of sine pulse in three levels and the use of an input filter provide to this converter a unity power factor and a practically reduced total harmonic distortion for input grid.