Passive lossless buffering circuit of power factor correction circuit

Abstract

The invention discloses a passive lossless buffering circuit of a power factor correction circuit. The passive lossless buffering circuit comprises boost inductors, auxiliary coupling inductors, a main power switch, a buffering capacitor and fast recovery diodes, wherein a main boost inductor and a secondary boost inductor are connected; the secondary boost inductor is connected with a first auxiliary coupling inductor and one end of a second auxiliary coupling inductor; the other end of the second auxiliary coupling inductor, a first diode anode, a third diode anode and the main power switch are connected; the other end of the first auxiliary coupling inductor, a second diode anode and one end of the buffering capacitor are connected; the other end of the buffering capacitor and a third diode cathode are connected; the connection point of the buffering capacitor and the third diode is connected with a fourth diode anode; and the cathodes of the first diode, the second diode and the fourth diode are electrically connected. With the adoption of the passive lossless buffering circuit of the power factor correction circuit, the reverse recovery problem of the diode can be effectively controlled, the switching loss is reduced, the reverse recovery energy can be stored by the buffering capacitor and the energy is transmitted to a load, so that the conversion efficiency is improved, and at the same time, the electromagnetic interference of electric equipment is effectively reduced.

Description

technical field [0001] The invention relates to the field of switching power supplies, in particular to a passive lossless snubber circuit of a power factor correction circuit. Background technique [0002] Mains power is an energy source that our life cannot do without, and many electrical equipment will generate a lot of harmonic interference due to various reasons, which will have a lot of impact on the city power grid. [0003] Electrical equipment such as converters have two operating modes, continuous current mode and discontinuous current mode. When the converter works in continuous current mode, there will be a commutation process in which the switching tube and the rectifier tube are in a common state when the switching tube is turned on. During the process, the current of the rectifier tube will turn to the switch tube sharply, and the current of the switch tube rises too fast to cause a large loss of the switch tube, and the current of the rectifier tube drops to...

AI Technical Summary

Problems solved by technology

[0003] Electrical equipment such as converters have two operating modes, continuous current mode and discontinuous current mode. When the converter works in continuous current mode, there will be a commutation process in which the switching tube and the rectifier tube are in a common state when the switching tube is turned on. During the process, the current of the rectifier tube will turn to the switch tube sharply, and the current of the switch tube rises too fast to cause a large loss of the switch tube, and the current of the rectifier tube drops too fast, which may cause a large reverse recovery current, which eventually leads to a decrease in the efficiency of the converter and High electromagnetic noise and other adverse effects

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