Active clamping push-pull buck-boost DC converter

Abstract

The invention discloses an active clamping push-pull buck-boost DC converter, and belongs to the power electronic conversion technology. The circuit structure is formed by cascading an input direct-current power supply, an input filter circuit, an active clamping push-pull circuit, a high-frequency transformer, a rectifying circuit, an output filter circuit and a direct-current load. According to the active clamping push-pull circuit, a clamping capacitor is connected in series between two switches of a traditional push-pull circuit, so that two active clamping circuits are formed, and inductance energy feedback is achieved. The rectifying circuit has a transformer short-circuit function, and is modified on the basis of a diode rectifying circuit, and a diode is replaced by a two-quadrant switch; and the converter controls storage and release of energy through simultaneous on-off of the primary side full-control switch and the secondary side full-control switch, can convert unstable direct current into stable and high-quality direct current, and has the advantages of being simple in circuit structure, isolated in input and output, low in power switch voltage stress, easy to control, high in reliability and the like. The converter is suitable for medium and small capacity low-voltage high-frequency isolation DC conversion occasions.

Description

Technical field: [0001] The active clamp push-pull lifting pressure DC converter proposed by the present invention belongs to power electronics. Background technique: [0002] With the development of power electronics, miniaturization, lightweight, high efficiency, high reliability and high stability of power electronic devices are the direction of the development of power electronic devices. Today, in a new energy power generating system in low-voltage input such as solar energy, fuel cells, the straight-line converter is an important part of it. [0003] Traditional push-pull DC converter, such as figure 1 As shown, since the structure is simple, the transformer is bidiren, the core utilization is high, and it is necessary to have a magnetic reset and have an isolation effect. It is widely applied to these low-voltage input electrical energy conversion applications, but the traditional push-pull DC converter For the BUCK circuit, it is difficult to implement the wide range of i...

AI Technical Summary

Problems solved by technology

[0003] Traditional push-pull DC converters, such as figure 1 As shown, due to its simple structure, bidirectional magnetization of the transformer, high utilization rate of the magnetic core, no need for magnetic reset and isolation effect, it is widely used in these low-voltage input power conversion occasions, but most of the traditional push-pull DC converters As a Buck circuit, it is difficult to achieve a wide range of input and output changes. In addition, due to the effects of the transformer leakage inductance and the stray inductance of the power loop in the converter, when the power tube is turned off in the traditional push-pull converter, both ends of the power tube will be High voltage spikes are generated, which have adverse effects on the selection of power devices, system stability, etc.

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