Interleaved parallel three-phase PFC circuit

Abstract

The invention discloses an interleaved parallel three-phase PFC circuit comprising a converter circuit and an input inductive circuit. The converter circuit comprises first and second Vienna converters. The three phases of input of the first Vienna converter are respectively connected with the three phases of input of the second Vienna converter. The three levels of output of the first Vienna converter are respectively connected with the three levels of output of the second Vienna converter and connected with the midpoint of an output capacitor. The input inductive circuit comprises three inductors which are respectively connected in series between the A, B and C phases of output ends of an AC power supply and the three phases of input ends of the converter circuit. Compared with the circuits in the prior art, the input inductive circuit is additionally arranged so that the input and output current ripple is enabled to be lower; besides, current equalization can be realized under the effect of the input inductive circuit when the component properties of the two interleaved parallel Vienna converter circuits are largely different so that standard exceeding of device thermal stress caused by uneven heating of branch devices and overcurrent protection triggered by uneven branch current can be prevented, and the circuit is enabled to normally work.

Description

technical field [0001] The invention relates to the field of power conversion circuits, in particular to an interleaved parallel three-phase PFC circuit. Background technique [0002] With the rapid development of power electronics technology, power factor correction has been widely studied. At present, single-phase PFC technology has basically matured and is widely used in various power electronic devices such as switching power supplies. At the same time, with the increasing requirements of the modern power supply system for the three-phase AC input equipment of the power grid, the three-phase PFC technology has gradually attracted widespread attention and has been widely studied. [0003] Such as figure 1 As shown, the interleaved parallel three-phase PFC circuit in the prior art uses two Vienna converters in parallel to achieve the purpose of reducing stress. Although this method reduces the input and output current ripple to a certain extent, it is prone to current un...

AI Technical Summary

Problems solved by technology

Although this method reduces the input and output current ripple to a certain extent, it is prone to current unevenness caused by device deviations in different branches, which eventually leads to uneven heating of the device due to uneven current, which triggers protection and even damages , affecting the normal operation of the circuit

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