Zeta type three-level AC-AC converter

Abstract

This invention discloses a Zeta three-level AC-AC converter, which converts a DC Zeta topological single-way switch tube to a dual-way switch tube, adds a supply level mode branch and a dual switch tube isoalting it and adds a zero-level mode dual-switch tube in front of the output filter combined with a non-complementary control strategy, and input and output filters are added to the supply and output ends to make up of a circuir topological structure of stable and adjustable same frequency and high quality sine AC circuit, the power conversion series of this invention is less and dual power flow can be realized, the voltage spectrum character in front of the output filter is good, conversion efficiency and power density are increased, the step regulation can be realized and the volume and weight of the output filter can be reduced and the output waveform quality is increased.

Description

technical field [0001] The invention belongs to power electronic conversion technology, in particular to a Zeta type three-level AC-AC converter. Background technique [0002] AC-AC conversion technology is a conversion technology that uses power semiconductor devices to convert AC power of a certain frequency and amplitude into AC power of the same or another frequency and amplitude. It is widely used in National defense, industrial and mining enterprises, scientific research institutes, university laboratories and daily life. [0003] The traditional AC voltage regulation includes transformer voltage regulation, thyristor voltage regulation, AC chopper voltage regulation and transformation voltage regulation with rectification and inverter intermediate links. Summarize their characteristics. Although each has its own advantages, its defects are also obvious, and the volume is large. , heavy weight, high output harmonic distortion, high voltage borne by the switching tube,...

AI Technical Summary

Problems solved by technology

The converter has simple topology, single-stage power conversion (low frequency AC LFAC-low frequency AC LFAC), bidirectional power flow, high input side power factor, good output filter front-end voltage spectrum characteristics, high conversion efficiency and power density, suitable for high voltage It has the advantages of large-capacity AC-AC conversion, etc., but it can only be used for step-down regulation, and the requirements for floating capacitance and balance control are relatively strict, and its circuit topology determines that it should be complementary when it is converted in three-level mode. type control strategy, resulting in greatly reduced reliability of circuit work, and the ability to carry different loads is not strong

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