A three-phase pfc switching power supply circuit

Abstract

The present invention discloses a three-phase PFC switching power supply circuit. The circuit comprises an interleaved PFC circuit, a three-phase input power supply, and a direct current output terminal. The interleaved PFC circuit comprises two n-phase interleaved PFC circuits and a rectifier bridge circuit. A phase difference between branch circuits of a same n-phase interleaved PFC circuit is 360 / n degrees, an input terminal of the first n-phase interleaved PFC circuit is connected to a first phase of the three-phase input power, and an input terminal of the second n-phase interleaved PFC circuit is connected to a second phase of the three-phase input power. The rectifier bridge circuit comprises a first diode and a second diode, wherein an anode of the first diode is connected to a negative electrode of the direct current output terminal, a cathode of the first diode is connected to an anode of the second diode, and a cathode of the second diode is connected to a positive electrode of the direct current output terminal. The second phase of the three-phase input power is connected to the cathode of the first diode. According to the three-phase PFC switching power supply circuit provided by the present invention, on the premise that circuit reliability is substantially unchanged, PFC circuit efficiency and a power factor can be further improved, so that the application prospect is wide.

Description

[technical field] [0001] The invention relates to a high-frequency switching power supply, in particular to a three-phase PFC switching power supply circuit. [Background technique] [0002] With the development of switching power supply technology, due to the limitation of input harmonic current, three-phase PFC (power factor correction, power factor correction) circuit has become an indispensable part of switching power supply, and the volume requirement of switching power supply is getting smaller and smaller, and the power requirement Larger and larger, the efficiency requirements are higher and higher, in order to save energy. [0003] Such as figure 1 As shown, the traditional six-tube three-phase PFC circuit is relatively simple, generally composed of a switching tube rectifier bridge, a three-phase inductor, a switching device, and an output capacitor. This three-phase PFC circuit can realize bidirectional energy flow, and the switching frequency is generally low. T...

AI Technical Summary

Problems solved by technology

[0003] like figure 1 As shown, the traditional six-tube three-phase PFC circuit is relatively simple, and generally consists of a switching tube rectifier bridge, a three-phase inductor, a switching device, and an output capacitor. This three-phase PFC circuit can realize bidirectional energy flow, and the switching frequency is generally low. The large size of the inductor is not conducive to improving the power density. This kind of circuit generally adopts vector control, and the control is more complicated.

[0004] With the advancement of technology, the three-phase Vienna PFC circuit is a good choice. The three-phase PFC circuit can be decoupled and controlled, and the energy flows in one direction. For a typical topology, see figure 2 .However, the three-phase Vienna PFC uses double busbar capacitors, the output diode will reduce the efficiency, the cost is high, and the voltage of the two output capacitors is easy to be unbalanced

Images