Non-isolated direct-current converter type differential three-level inverter

Abstract

The invention discloses a non-isolated direct-current converter type differential three-level inverter. The circuit structure of the inverter consists of a power supply, an input filter, two bidirectional three-level direct-current converters, an output filter and an alternating current load, wherein the bidirectional three-level direct-current converters are connected in a differential way, i.e. input ends are connected in parallel and output ends are connected in series. By the inverter, the function of converting unstable and low-quality direct-current voltage into stable and high-quality sine alternating-current voltage as required can be realized. A circuit topology family of non-isolated direct-current converter type differential three-level inverters, including Boost type, Buck type, Buck-Boost type, Cuk type, Sepic type and Zeta type, is obtained by changing the type of the bidirectional three-level direct-current converters. The inverter has the characteristics of simple circuit topology, capability of adapting to wider voltage input range, bidirectional power current, single-stage conversion, small volume, light weight, low cost, simple control, high conversion rate, high load adaptability, high dynamic performance and the like, and is applied to a high-voltage input occasion.

Description

technical field [0001] The invention belongs to the technical field of power electronic conversion, in particular to a non-isolated DC converter type differential three-level inverter. Background technique [0002] DC-AC inverter technology is a static converter device that uses power semiconductor devices to convert DC power into sinusoidal AC power with a fixed frequency or adjustable frequency. It is used for AC loads and is widely used in national defense, industrial and mining enterprises, and scientific research. Institutions, university laboratories and everyday life. [0003] At present, domestic and foreign power electronics researchers mainly focus on two aspects of research on DC-AC inverters. One is the research on two-level DC-AC converters such as non-electrically isolated, low-frequency and high-frequency electrically isolated; the other is research on multi-level inverters. The multi-level inverter has the advantages of low voltage stress of the switching t...

AI Technical Summary

Problems solved by technology

Afterwards, Ramon Caceres proposed the Boost DC converter inverter, and some other scholars also successively proposed Buck DC converter and Buck-boost DC converter inverters. Although the above inverters have many advantages, they are all Two-level inverters, and in the case of high-voltage electric energy conversion, there are defects such as high switching voltage stress, high harmonic content of output voltage, large loss, and large volume of energy storage components.

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