Twelve-phase three-level H-bridge direct current side cascade propulsion frequency converter and capacitor voltage balance control method

Abstract

The invention discloses a twelve-phase three-level H-bridge direct-current side cascade propulsion frequency converter which is formed by cascading the direct-current sides of two six-phase three-level H-bridge propulsion frequency converters, wherein the cascade upper-end propulsion frequency converter is provided with a non-return diode at a direct-current input positive electrode, the cascade lower end propulsion frequency converter is provided with a non-return diode at a direct current input negative electrode; the three-level H-bridge direct-current side cascade topology suitable for direct-current 10kV is developed based on a mature three-level H-bridge topology, and compared with other five-level or modular multi-level topologies, the three-level H-bridge direct-current side cascade topology does not involve an absorption loop or a complex large commutation loop, and is provided with a simple main circuit. The invention further discloses a capacitor voltage balance control method; neutral-point potential adjustment based on zero-sequence voltage injection is adopted; three-level upper and lower H bridges are adjusted through loads; and themethod is easy to implement and does not affect an original control strategy.

Description

technical field [0001] The invention belongs to the technical field of high-power electric energy conversion, and in particular relates to a twelve-phase three-level H-bridge DC side cascaded propulsion frequency converter and a capacitor voltage equalization control method. Background technique [0002] With the increasing maturity of high-power power electronic technology, high-power frequency conversion speed regulation technology has also been developed rapidly, thus greatly promoting the research and development of large-capacity all-electric propulsion, and more and more ships adopt or begin to use electric power. propulsion instead of traditional mechanical propulsion. Compared with traditional mechanical propulsion, electric propulsion has the advantages of high efficiency, large payload, good flexibility, good maintainability, and good fuel economy. The medium-voltage multi-phase motor system can meet the requirements of large capacity, good reliability and high to...

AI Technical Summary

Problems solved by technology

[0006] It can be seen from the above table that the existing foreign 10kV voltage inverter products have low adaptability, and it will be difficult to meet the adaptability requirements of ship DC 10kV medium-high voltage multi-phase large-capacity inverters

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