Single-phase inverter

Abstract

The invention discloses a single-phase inverter. The positive terminal of a direct current power supply is connected with the first end of a first switching tube; the second end of the first switching tube is connected with the negative terminal of the direct current power supply through a second switching tube, a third switching tube and a fourth switching tube which are sequentially connected in series; the second end of the first switching tube is connected with the negative terminal of the direct current power supply through a fifth switching tube, a sixth switching tube and a seventh switching tube which are sequentially connected in series; a first clamping diode is connected between the common terminal of the third switching tube and the fourth switching tube and the common terminal of the fifth switching tube and the sixth switching tube; a second clamping diode is connected between the common terminal of the sixth switching tube and the seventh switching tube and the common terminal of the second switching tube and the third switching tube; an alternating current load is connected between the common terminal of the second switching tube and the third switching tube and the common terminal of the fifth switching tube and the sixth switching tube; and the second switching tube is reversely connected in parallel with a second diode, and the fifth switching tube is reversely connected with a fifth diode. The single-phase inverter provided by the embodiment of the invention can be used for improving the quality of output electric energy of the inverter.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to a single-phase inverter. Background technique [0002] According to different application occasions and control methods of inverters, they can be divided into off-grid inverters and grid-connected inverters. In the grid-connected inverter, according to whether it has a transformer, it can be divided into a transformer-isolated inverter and a transformerless inverter. Due to its simple system structure, high efficiency, small size, low cost and many other advantages, the transformerless inverter has been developed rapidly and has become the mainstream of photovoltaic medium and small power. [0003] However, since the transformerless inverter cannot achieve electrical isolation between the DC input source and the AC load, the leakage current problem is one of the key indicators of its reliability. In order to obtain higher efficiency, a unipolar modulation strategy is ...

AI Technical Summary

Problems solved by technology

[0003] However, since the transformerless inverter cannot achieve electrical isolation between the DC input source and the AC load, the leakage current problem is one of the key indicators of its reliability.

In order to obtain higher efficiency, a unipolar modulation strategy is usually adopted for transformerless inverters, and the traditional H4 topology can no longer take into account both leakage current and high efficiency.

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