Auxiliary resonant conversion pole T-type three-level soft switching inverter circuit and modulation method

Abstract

The invention provides an auxiliary resonant conversion pole T-type three-level soft switch inverter circuit and a modulation method thereof. The circuit includes a T-type main inverter circuit, an auxiliary resonant converter circuit, a filter circuit and a load. The T-type main inverter circuit includes four switch tubes with anti-parallel diodes and two identical supporting capacitors, and the auxiliary resonant converter circuit includes two auxiliary switch tubes with anti-parallel diodes, four resonant capacitors and a resonant inductance. The filter circuit is an LC filter circuit. The modulation method provided by the invention can realize the zero-voltage switching of the main switching tube and the zero-current switching of the auxiliary switching tube. The invention can reduce T-type three-level hard switching loss, improve system efficiency and reduce electromagnetic interference.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to an auxiliary resonant conversion pole T-type three-level soft-switching inverter circuit and a modulation method. Background technique [0002] With the rapid development of power electronics technology, people's demand for inverters with high frequency, miniaturization and light weight, high power and high power density is also increasing. However, with the increase of switching frequency, the use of conventional pulse width modulation technology will face many problems. On the one hand, the switching loss of the switching tube will increase, and on the other hand, the system will generate electromagnetic interference (EMI) to the outside. [0003] In order to solve the above problems, since the 1980s, the soft switching technology has been deeply studied, and various topological structures and modulation strategies have been continuously optimized and improved. Soft ...

AI Technical Summary

Problems solved by technology

[0009] 1. The added double auxiliary resonant commutation circuit uses more auxiliary switching tubes and auxiliary diodes, which increases the hardware cost;

[0010] 2. There are many auxiliary switching tubes, which increases the difficulty of the modulation method of the auxiliary switching tubes;

[0011] 3. The inverter circuit is aimed at two-level circuits, and it is difficult to apply it to three-level circuits

Images