Bidirectionally isolating type series resonance DC/DC converter

Abstract

The invention relates to a bidirectionally isolating type series resonance DC / DC converter (100) which comprises voltage-stabilizing capacitors (22, 32), high-frequency converters (20, 50), series resonance circuits (30, 40), a high-frequency transformer (28) and an energy storage unit (60), wherein the voltage-stabilizing capacitors (22, 32) are used for enhancing the stability of a DC voltage; the high-frequency converters (20, 50) have the same structure and comprise four switching elements inversely connected in parallel with a rapid diode and can be used for inversion and rectification; the series resonance circuits are used for converting three kinds of discrete levels output by corresponding high-frequency converters into sinusoidal waveforms and can be used for softly switching the switching elements of the corresponding high-frequency converters, at the same time, only one series resonance circuit (30 or 40) acts; and the high-frequency transformer (28) can be used for isolation and transformation. The transformer (100) can be used for greatly converting the DC voltage, has high efficiency, and can be applied to an electric vehicle power supply, standby power supplies of large-scale equipment, and the like.

Description

technical field [0001] The invention relates to a DC / DC converter, in particular to a bidirectional, isolated DC / DC converter based on series resonance soft switching. Background technique [0002] Bidirectional DC / DC converters are widely used in electric vehicles, energy recovery systems for high-power equipment, and backup power supplies for high-power equipment. The energy storage element adopts a supercapacitor or a storage battery, and its charging and discharging are controlled by a bidirectional DC / DC converter. [0003] At present, the topology of bidirectional DC / DC converters is divided into isolated and non-isolated converters. The structure of the isolated converter is relatively complicated. Considering the cost problem, most of them adopt the non-isolated BUCK / BOOST topology. Due to structural limitations, in the prior art, there are mainly two problems in bidirectional DC / DC converters. First, the gain of the BOOST converter is generally low, usually less t...

AI Technical Summary

Problems solved by technology

The bidirectional DC / DC converter of this invention is non-isolated, and requires the design of filter units on both sides, which is relatively cumbersome. If the filter design is unreasonable, the two sides will affect each other, increasing the harm of harmonics between the two sides, and the voltage The conversion range is small, and the energy storage units are connected in series, requiring a voltage equalizing circuit, and the energy storage is slow

Images