Current source type three-level AC/AC converter

Abstract

The invention discloses a current source type three-level AC / AC converter. The current source type three-level AC / AC converter is formed by an input alternating current power supply, a voltage-dividing capacitor, a high-frequency isolation type three-level conversion unit, a frequency converter, an output filter and an output alternating current load which are connected in sequence. According to the converter, on the basis of a traditional AC / AC converter, the two ends of the input alternating current power supply are in parallel connection with two capacitance partial voltages, the front end of the converter can generate three levels including U, U / 2 and -Uo / n (n=N2 / N1= ), voltage stress of a switch tube is reduced, and output voltage waveform quality is improved. The current source type three-level AC / AC converter has the advantages that voltage stress of a switch device is small, front end voltage spectral characteristics of the output filter are good, the size of the output filter is small, and an alternating current load and alternating current power supply high-frequency electrical isolation can be achieved; and the current source type three-level AC / AC converter can be applied to the application occasions with high voltage and high power and is wide in application prospect.

Description

technical field [0001] The invention belongs to the technical field of power electronic conversion, in particular to a current source 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 into the required constant voltage and constant frequency AC power through variable voltage and frequency conversion. It is also called a cycle converter. Different from ordinary inverters, there is no link from AC rectification to DC and then inverter to AC. It is an AC-AC conversion structure. This technology is widely used, including AC voltage regulators, AC voltage regulators, etc. Compressors and UPS have become necessary terminal equipment for AC power supply systems. So far, domestic and foreign power electronics researchers have mostly focused on AC-DC converters and two-level AC-AC converters; research on multi-level AC / AC converters is very important. Less,...

AI Technical Summary

Problems solved by technology

However, the AC / AC converter of the two-level frequency conversion link cannot meet the requirements of high-power occasions

[0006] For multi-level AC / AC converters, existing technologies are limited to non-isolated, low-frequency or intermediate-frequency isolated AC-DC-AC three-level AC / AC converters and BUCK non-isolated AC-AC three-level converters. Level AC / AC Converter

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