Scalable Multilevel Rectifier

Abstract

The scalable multilevel rectifier, taking seven levels as an example, is mainly supported by four sub-modules and a diode bridge, and is composed of a filter inductor, three series capacitors, an AC power supply and a resistive load. The seven-level rectifier can be extended to an n-level rectifier, and the number of levels is n=2 k +3, k=1, 2, 3..., k is a positive integer, that is, the number of sub-modules in this topology can be increased according to the principle of "multiplication and splitting" to achieve the purpose of outputting more levels, which is scalable Strong and highly modular features. The invention is beneficial to reduce the size of the filter inductance, and compared with the traditional two-level rectification circuit, the harmonic content is lower, the output voltage is more stable, and it is suitable for medium-high voltage and high-power occasions.

Description

technical field [0001] The invention relates to a rectifier, in particular to an expandable multilevel rectifier. Background technique [0002] As the development of domestic power conversion technology has become mature, the development of power electronic converters is also developing towards higher frequency and higher power. And the power capacity is relatively high, the withstand voltage capability of power electronic devices will be limited, and the high-order harmonics generated on the grid side will also affect the normal operation of the power system. For this reason, at the IEEE Industrial Applications (IAS) annual meeting in 1980, some scholars first proposed the concept of "multi-level", which laid a solid foundation for the development of high-voltage and large-capacity converters. After that, A large number of multi-level topological structures and control strategies have been proposed one after another, and are widely used in current wind power generation, gr...

AI Technical Summary

Problems solved by technology

[0002] As the development of domestic power conversion technology has become mature, the development of power electronic converters is also developing towards higher frequency and higher power. And the power capacity is relatively high, the withstand voltage capability of power electronic devices will be limited, and the high-order harmonics generated on the grid side will also affect the normal operation of the power system

For this reason, at the IEEE Industrial Applications (IAS) annual meeting in 1980, some scholars first proposed the concept of "multi-level", which laid a solid foundation for the development of high-voltage and large-capacity converters. After that, A large number of multi-level topological structures and control strategies have been proposed one after another, and are widely used in current wind power generation, grid-connected power generation and other industrial occasions. However, the multi-level rectifier structure in the prior art is complex and diverse, and the integration level is not high. The disadvantage of poor flexibility, so the multi-level topology with simple structure, high degree of modularization, and simple commutation method has become a research hotspot in the academic circle

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