Two-way DC converter

Abstract

The invention discloses two two-way DC converters, and belongs to the technical field of power electronics converters. The two two-way DC converters are in a boosting-bucking type and a boosting bucking type respectively. A circuit structure comprises a first power supply and a second power supply (V1 and V2), a first filter capacitor and a second filter capacitor (C1, C2), a first diode and a second diode (D1 and D2), a first switching tube and a second switching tube (Q1 and Q2), a first coupling inductor and a second coupling inductor (Lc1, Lc2) and a filter inductor (L), wherein two coupling inductors are mutually coupled together by sharing an inductance core. Switching tubes converting power in two directions are mutually independent, which avoids the defect that the conversion efficiency is reduced because of reverse recovery of parasitic diodes of the switching tubes when the switching tube of the conventional two-way converter is multiplexed, and improves the reliability of the converter at the same time. When the switching tube in one direction has a fault, the power conversion in other direction cannot be influenced. The converters are particularly suitable for high-voltage and high-power conversion occasions having higher requirements on the conversion efficiency and the reliability.

Description

technical field [0001] The invention relates to two kinds of converters, in particular to two bidirectional direct current converters of a step-up and step-down type and a buck-boost type, and belongs to the technical field of power electronic converters. Background technique [0002] The bidirectional DC converter can realize the bidirectional transmission of energy through the double-quadrant operation of the DC converter. It is functionally equivalent to two unidirectional DC converters. It is a typical "one machine with two uses" equipment. In occasions requiring two-way energy flow, such as battery charging and discharging, new energy power generation, and aerospace power supply systems, it can greatly reduce the volume and weight of the system, which has high research value. [0003] Traditional step-up-buck bidirectional DC converters such as figure 1 shown. Switch tube Q 1 and Q 2 Generally, switching devices with parasitic body diodes, such as MOSFETs, are used....

AI Technical Summary

Problems solved by technology

use figure 2 In the diode-blocking step-up and step-down bidirectional DC converter shown, on the one hand, the diodes connected in series with the switch tubes introduce conduction loss, resulting in a decrease in efficiency; on the other hand, the number of diodes used is doubled, which increases the cost

[0005] In addition, in applications with higher requirements on the reliability of bidirectional converters, when the power conversion in one direction fails, the other direction is not affected. In this case, two unidirectional converters are generally combined It is used as a bidirectional converter, but due to the increase of passive components such as inductors and capacitors, the weight and volume of the converter increase

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