NON-ISOLATED THREE-PHASE PFC CONVERTER AND CONTROL METHOD THEREFOR

摘要

A non-isolated three-phase PFC converter and a control method therefor. The converter comprises a switch unit, a rectification unit and an energy storage flyback unit. The switch unit comprises three switch groups (Q1Q2, Q3Q4, Q5Q6); the three switch groups (Q1Q2, Q3Q4, Q5Q6) are respectively arranged on three phase lines (A, B, C) of an accessed three-phase three-wire power source; and the three switch groups (Q1Q2, Q3Q4, Q5Q6) are respectively connected with the rectification unit through the three phase lines (A, B, C). The energy storage flyback unit comprises first to second flyback inductors (L1, L2) and a filtering capacitor (C1); a positive electrode end of the rectification unit is serially connected with one end of the first flyback inductor (L1) through a positive electrode bus (BUS+), and a negative electrode end of the rectification unit is serially connected with one end of the second flyback inductor (L2) through a negative electrode bus (BUS-); the filtering capacitor (C1) is provided between the positive electrode bus (BUS+) and the negative electrode bus (BUS-); the other end of the first flyback inductor (L1) and the other end of the second flyback inductor (L2) are respectively connected with two ends of the filtering capacitor (C1). The converter has a simple structure and a relatively simplified control logic, and is applicable for high power density scenarios.