High-frequency isolation type three-electric-level DC-DC (direct current-direct current) convertor based on Cuk convertor

Abstract

The invention discloses a high-frequency isolation type three-electric-level DC-DC (direct current-direct current) convertor based on Cuk convertor. In the convertor, two coupling capacitors in a DC non-isolation type Cuk three-electric-level topology without a transformer are respectively disassembled into two capacitors, and two serially-connected transformers are respectively inserted between the two capacitors, the middle connecting point of primary sub sides of two transformers is respectively connected with the middle point of two switching tubes at left side and two booster diodes at right side, and an input filter and an output filter are respectively arranged at the input end and the output end to form a circuit topological structure which converts unstable direct current into adjustable direct current. In the invention, the power conversion stage number is less, power switching devices are less, boosting regulation can be realized, and the converter has the electrical isolation character; in addition, spectral characteristic of the voltage at the front end of the output filter is good, the conversion efficiency and power density are improved, and the volume and weight ofthe output filter are reduced.

Description

technical field [0001] The invention belongs to power electronic conversion technology, in particular to a high-frequency isolated three-level direct-to-direct converter based on a Cuk converter. Background technique [0002] Direct-to-direct (DC-DC) conversion technology is a conversion technology that uses power semiconductor devices to convert DC power into another fixed voltage or adjustable voltage DC power. It is widely used in national defense, industrial and mining enterprises, and scientific research institutes. institutes, university laboratories and everyday life. [0003] The DC voltage regulating circuit mainly includes a DC chopper circuit, an indirect DC converter circuit, etc. There are many types of DC chopper circuits, including six basic chopper circuits: buck chopper circuit, boost chopper circuit, buck-boost chopper circuit, Cuk chopper circuit, Sepic chopper circuit and Zeta chopper circuit, in addition There are also bridge composite chopper circuits...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the shortcomings of high-power power supply power switch tube voltage stress is too large, direct-to-direct converters generally have many conversion stages, complex circuits and no electrical isolation function, the present invention provides a high-frequency isolated three-phase converter based on Cuk converter. Level direct-to-direct converter, which has the advantages of single-stage power conversion, bidirectional power flow, good spectral characteristics of output filter front-end voltage, buck-boost conversion, reduced voltage stress of switching devices, and effective electrical isolation.

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