A new input-voltage feedforward harmonic-injection technique with nonlinear gain control for single-switch, three-phase, DCM boost rectifiers

A new input-voltage feedforward harmonic-injection technique for a single-s witch, three-phase, discontinuous-conduction-mode boost rectifier is introd uced. With this technique, rectification with a low total harmonic distorti on that meets the IEC555-2 requirements can be achieved. In addition, the r ectifier shows an excellent transient performance which dramatically reduce s the rectifier's output voltage overshoots during line-voltage step-up tra nsients. Moreover, by the addition of a nonlinear gain-control circuit, the de gain of the DCM boost rectifier at light load is adaptively reduced so that the stability of the rectifier at light load is achieved. The performa nce of the proposed injection technique was verified on a 6-kW prototype re ctifier.