High voltage gain bidirectional DC-DC (direct current-direct current) converter based on switching capacitors and coupling inductors

Abstract

The invention discloses a high voltage gain bidirectional DC-DC (direct current-direct current) converter based on switching capacitors and coupling inductors. The high voltage gain bidirectional DC-DC converter based on the switching capacitors and the coupling inductors is formed by combining Boost convertors, the coupling inductors and the switching capacitors in interleaved mode. An electric circuit of the high voltage gain bidirectional DC-DC converter based on the switching capacitors and the coupling inductors comprises n / 2 coupling inductors T1[L1, L2], T2[L3, L4]... T(n / 2)[L(n-1), Ln], 2n high frequency power switches S1, S2... Sn and Q1, Q2... Qn, N-1 high frequency switching capacitors C1, C2... C(n-1) and two input and output filter capacitors CL and CH. The high voltage gain bidirectional DC-DC converter based on the switching capacitors and the coupling inductors can effectively reduce current stress of a low voltage side power device and voltage stress of a high voltage side power device, further reduces the ripple of an input current and decrease the inductor size by using the coupling inductors, improves efficiency of an exchanger, and achieves bidirectional DC-DC conversion high in efficiency and high in voltage gain. According to high voltage gain bidirectional DC-DC converter based on the switching capacitors and the coupling inductors, an interleaved technology, a magnetic integration technology and a switching capacitor technology are combined, and therefore novel topology of the high voltage gain bidirectional DC-DC converter based on the switching capacitors and the coupling inductors not only has characteristics of being low in ripple of the input current and easy to design in EMT mode of an interleaved converter, but also achieves the purposes that a transformation ratio of input voltage and output voltage is large and switch voltage stress is low.

Description

technical field [0001] The invention relates to the technical field of high voltage gain and bidirectional DC-DC converters, and is a novel circuit with simple circuit structure, low voltage / current stress of switching devices, high efficiency and flexible expansion of boost ratio. Background technique [0002] With the rapid consumption of traditional fossil energy (such as oil, coal, natural gas, etc.), and the increasing problems of the world's energy crisis and environmental pollution, the rational development and utilization of green renewable energy has become an urgent need for human beings. . With the rapid consumption of traditional fossil energy (such as oil, coal, natural gas, etc.), and the increasing problems of the world's energy crisis and environmental pollution, the rational development and utilization of green renewable energy has become an urgent need for human beings. . For renewable energy, solar photovoltaic power generation, wind power generation and...

AI Technical Summary

Problems solved by technology

[0008] ③In some occasions where the input-output voltage conversion ratio is large, the switching device needs to work in an extreme duty cycle state, which is not conducive to the improvement of the efficiency of the converter, and limits the improvement of the operating frequency of the switching device

However, the large inductance and input and output filter capacitors lead to poor dynamic characteristics of automatic current sharing, and the converter is prone to current spikes or even instability. In addition, its highest efficiency in boost / buck mode is only 91% and 90%. %

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