Isolated boost bidirectional DC-DC converter topological structure

Abstract

The invention discloses a topological structure of an isolated boost bidirectional DC-DC converter. The circuit comprises a pre-stage Boost circuit, an integrated transformer and a post-stage H-bridgecircuit, wherein the pre-stage Boost circuit comprises a first two-phase interleaved Boost converter, a second two-phase interleaved Boost converter and a third two-phase interleaved Boost converter;the integrated transformer is of a coupling inductance structure and comprises a Boost inductance part and an ideal transformer structure, the first two-phase interleaved Boost converter is connectedwith the Boost inductance part of the integrated transformer in series, and the ideal transformer structure of the integrated transformer is connected with the post-stage H-bridge circuit in series.The topological structure is few in selected devices, simple in circuit and high in integration level, the problem that input current is discontinuous can be well solved, input current ripples and output voltage ripples are greatly restrained, and the topological structure can be applied to a lithium battery application scene with higher requirements for the current ripples.

Description

technical field [0001] The invention relates to the technical field of power electronics and electric energy conversion in electrotechnical technology, in particular to a novel topology of an isolated boost bidirectional DC-DC converter. Background technique [0002] With the intensification of energy crisis and global warming, renewable energy sources such as lithium batteries, solar energy, and wind energy have attracted more and more attention. Compared with traditional batteries, lithium batteries have the advantages of long cruising range, repeated use, clean and pollution-free, and high energy density. Isolated boost bidirectional DC-DC converters are widely used in renewable energy fields such as lithium batteries due to the advantages of bidirectional energy flow, high boost ratio, and adjustable ratio. [0003] The isolated boost bidirectional DC-DC converter is generally realized by a Boost converter and a DAB circuit, which has many devices and poor integration. ...

AI Technical Summary

Problems solved by technology

[0003] The isolated boost bidirectional DC-DC converter is generally realized by a Boost converter and a DAB circuit, which has many devices and poor integration

In the traditional isolated step-up bidirectional DC-DC converter, the input side inductance is large and cannot be integrated into the transformer, so the circuit will be bulky

For a single-phase coupled inductance boost converter, the input current is discontinuous during normal operation, so it is not suitable for lithium battery application scenarios that have high requirements on current ripple

In addition, the traditional isolated boost bidirectional DC-DC converter adopts the cascade connection of Boost converter and DAB circuit to achieve a high boost ratio, and the circuit components are many and the circuit is complex

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