Z-source two-stage matrix converter with fault-tolerant topology and control method thereof

Abstract

The invention discloses a Z-source two-stage matrix converter with a fault-tolerant topology and a control method thereof, and belongs to the technical field of matrix converter control. A fourth bridge arm used for replacing an open-circuit two-way switch is connected in parallel to the two ends of a rectifier-stage three-phase bridge arm of the Z-source two-stage matrix converter. For a rectifier-stage two-way switching tube open-circuit fault, a rectifier-stage space vector is re-divided to make each sector contain a unique nonzero vector so as to adjust the rectifier-stage fault-tolerant control strategy. When a rectifier-stage expected vector is located in the fault sector, the duty ratio of the shoot-through vector in the fault sector is adjusted, and the inverter-stage fault-tolerant control strategy is adjusted. According to the invention, fault-tolerant operation of the Z-source two-stage matrix converter is realized by the fourth bridge arm and the fault-tolerant control strategies in view of the open-circuit fault of one two-way switching tube of the rectifier stage, and the reliability and security of the matrix converter are improved.

Description

technical field [0001] The invention discloses a Z-source two-stage matrix converter with a fault-tolerant topological structure and a control method thereof, belonging to the technical field of matrix converter control. Background technique [0002] The AC power converter is the core of the AC frequency conversion system and the most important part of many electrical equipment. With the advancement of power electronics technology and the emergence of high-performance semiconductor power devices, AC power converters have also developed rapidly. Among them, the matrix converter, as a new type of AC converter, has the advantages of compact structure, small volume, good stability and long service life. The dual-stage matrix converter evolved from the matrix converter not only has the advantages of the traditional matrix converter, but also overcomes the disadvantages of the traditional matrix converter, such as complex commutation and the need for clamping circuits. [0003] ...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a Z-source two-stage matrix converter with a fault-tolerant topology and its control method, and propose a two-stage matrix converter with a fault-tolerant topology for the rectification stage. The converter and the fault-tolerant control method for the failure of the rectification stage of the two-stage matrix converter solve the technical problem that the converter cannot continue to operate after the failure of a bidirectional switch tube in the rectification stage of the two-stage matrix converter.

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