A switched-mode three-phase 200 A/48 V rectifier with input unity power factor

This paper describes a high efficiency (92% typ.), low input current distortion (<5%), 200 A/48 V plug-in rectifier, mounted in a ETSI standard (600×600 mm) cabinet. The input stage performs the triphase AC/DC conversion without neutral, generating +/- 400 V. The topology of this stage is a three-phase continuous boost with sinusoidal input currents performed by means of average input current mode control. This control is implemented using commercial single phase modulators with three independent current loops. The output stage uses two full bridges controlled by a single current-mode modulator. The two bridges are series connected; the topology and control circuitry used automatically perform the balance of the two voltages generated by the input stage and the correct output current sharing. The rectifier is fan-cooled and all components are board mounted. This goal has been reached putting in parallel smaller transformers and switching components