Phase-shifting control full-bridge zero-current converter and direct-current switching power source

Abstract

The invention relate to an efficient phase-shifting control full-bridge zero-current converter. The efficient phase-shifting control full-bridge zero-current converter includes the following components that: a phase-shifting full-bridge circuit composed of four switching tubes Q1, Q2, Q3 and Q4 and a transformer T, wherein Q1 and Q3 are leading bridge arms of phase-shifting full bridges, and Q2 and Q4 are lagging bridge arms of the phase-shifting full bridges; a direct current blocking capacitor Cb which is connected in series with the primary side of the transformer; and low-voltage and low-on inner resistance MOS transistors Q5 and Q6, wherein Q5 and Q6 are connected in series inversely and thereafter are connected between the direct current blocking capacitor and the transformer. After the leading bridge arms are switched off, the voltage of the direct current blocking capacitor enables loop current to reset to zero fast. The efficient phase-shifting control full-bridge zero-current converter has a current zero-crossing detection function. According to the phase-shifting control full-bridge zero-current converter, when the leading bridge arms are switched off, and the loop current is decreased to zero, the MOS transistor Q5(Q6) is switched off, and the reverse current of the lagging bridge arms is blocked; the two MOS transistors are connected in series with the primary sides of the traditional phase-shifting full bridges, so that the zero-current switching off of the lagging bridge arms can be realized. The phase-shifting control full-bridge zero-current converter can be widely applied to direct-current switching power sources.

Description

technical field [0001] The invention relates to a phase-shift control full-bridge zero-current converter and a DC power supply, and the converter can be used in the field of DC switching power supplies. Background technique [0002] As switching power supplies are widely used in various industries, users have put forward more and more stringent requirements for switching power supplies: high frequency, high power density, high efficiency and low electromagnetic interference. In high power applications, the full bridge circuit is most widely used. [0003] In order to meet the above requirements, many zero-voltage and zero-current soft switching circuits have emerged. There are mainly the following types: [0004] 1. The simplest method is to connect the saturated inductance in series with the primary side of the transformer, and use the characteristics of the saturated inductance to have a small impedance when the current is large and a large impedance when the current is ...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide a high-efficiency phase-shift control full-bridge zero-current converter and DC switching power supply, which solves the technical problem of low conversion efficiency of existing converters

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