The ordinary/traditional 3-phase 12-pulse rectifier consists of two 3-phase-bridge 6-pulse rectifiers and a phase-sifting device such as a 3-phase isolation transformer. The DC and the AC sides of two 3-phase-bridges can be connected in parallel or series, respectively, and both the Capacitor-Input-Type (CIT) and Inductor-Input-Type (IIT) (or Choke-Input-Type) are applicable. Therefore, in theory, there can be eights topologies in the ordinary 12-pulse rectifier with two 6-pulse three-phase bridge diode rectifiers depending on the DC connection, AC connection and the type of the 3-phase bridge (i.e., CIT or IIT). To reduce the size, weight and cost of the traditional 12-pulse rectifier topologies with an isolation transformer (Full-Isolation-Type), the isolation for one of the 3-phase bridge can be omitted (Semi-Isolation scheme). Practicability of the Semi-Isolation-Type 12-pulse rectifier family, consisting of eight different topologies, is studied. Then, combination of each the family member rectifier and a pulse-doubling auxiliary circuit to obtain 24-pulse nature are partially explored in this Synopsis.
展开▼
