CN203645541U - Single switch high gain boost DC/DC converter - Google Patents

Abstract

The utility model discloses a single switch high gain boost DC/DC converter. The single switch high gain boost DC/DC converter comprises a DC input power supply, a first inductor, a first diode, a second diode, a second inductor, a first capacitor, a switching tube, a third diode, a second capacitor, a third inductor, a third capacitor, a forth diode and an output capacitor. The DC input power supply is connected with the first inductor, the first capacitor, the switching tube, the third capacitor, the output capacitor and a load separately, and the first inductor is connected with the first and second diodes separately. The second inductor is connected with the first diode, the switching tube, the third diode, the second capacitor, the second diode and the first capacitor separately, and the second capacitor is connected with the third inductor and the fourth diode separately. The third diode is connected with the third inductor and the third capacitor separately, and the fourth diode is connected with the output capacitor and the load separately. Compared with the conventional single switch DC/DC converter, the single switch high gain boost DC/DC converter of the utility model possesses a high stead-state voltage gain, and is suitable for boosting a low DC voltage in a new energy power generation system into a high DC voltage.

Description

A kind of single switch high gain boost DC/DC converter

Technical field

The utility model relates to the technical field of DC/DC converter, refers in particular to a kind of single switch high gain boost DC/DC converter.

Background technology

In recent years, new forms of energy have obtained studying widely and applying, solar cell, fuel cell and super capacitor output in grid-connected power generation system are generally 24V/48V direct current, in order to realize the electrical connection of grid-connected power generation system and grid-connected system, need DC/DC converter that low dc voltage is risen to High Level DC Voltage after another mistake become civil power.And traditional single switch DC/DC converter widely at present, if the steady state voltage gain of BOOST, quadratic form BOOST converter is 1/ (1-D) and 1/ (1-D) ²(D is duty ratio).In the time that input voltage is lower, need very high duty ratio could realize High voltage output, but in the time that duty ratio increases, the current effective value of switching tube constant power semiconductor device increases, this current stress to power semiconductor requires high, and duty ratio increases, increase the conduction loss of switching tube, reduce the efficiency of converter.

Summary of the invention

The purpose of this utility model is to overcome the deficiencies in the prior art, and a kind of reliable, superior performance rational in infrastructure, single switch high gain boost DC/DC converter that efficiency is high are provided.

For achieving the above object, technical scheme provided by the utility model is: a kind of single switch high gain boost DC/DC converter, includes direct-current input power supplying, the first inductance, the first diode, the second diode, the second inductance, the first electric capacity, switching tube, the 3rd diode, the second electric capacity, the 3rd inductance, the 3rd electric capacity, the 4th diode, output capacitance; Wherein, one end of described direct-current input power supplying is connected with one end of the first inductance, and its other end is connected with one end of the first electric capacity, the drain electrode of switching tube, one end of the 3rd electric capacity, one end of output capacitance, one end of load respectively; The other end of described the first inductance respectively with the anode of the first diode and the anodic bonding of the second diode; One end of described the second inductance is connected with the negative electrode of the first diode, the drain electrode of switching tube, the anode of the 3rd diode, one end of the second electric capacity respectively, and its other end is connected with the negative electrode of the second diode and the other end of the first electric capacity respectively; The other end of described the second electric capacity respectively with one end of the 3rd inductance and the anodic bonding of the 4th diode; The negative electrode of described the 3rd diode is connected with the other end of the 3rd inductance and the other end of the 3rd electric capacity respectively; The negative electrode of described the 4th diode is connected with the other end of output capacitance and the other end of load respectively; Described output capacitance and load parallel connection.

Compared with prior art, tool has the following advantages and beneficial effect the utility model:

1, there is high steady state voltage gain than traditional single switch DC/DC converter, be applicable to the paramount direct voltage of low direct current voltage rise in grid-connected power generation system, realize the electrical connection of grid-connected power generation system and grid-connected system, be with a wide range of applications and very high promotional value;

2, operating efficiency is high, and the voltage stress of power switch pipe is lower than output voltage.

Brief description of the drawings

Fig. 1 is circuit theory diagrams of the present utility model.

Fig. 2 is the voltage and current waveform of a switch periods main element.

Fig. 3 a is one of circuit mode figure in a switch periods.

Fig. 3 b is two of the interior circuit mode figure of a switch periods.

Fig. 4 is the steady state voltage gain contrast figure of the utility model and traditional B OOST and quadratic form BOOST converter.

Embodiment

Below in conjunction with specific embodiment, the utility model is described in further detail.

Shown in Figure 1, the single switch high gain boost DC/DC converter described in the present embodiment, includes direct-current input power supplying, the first inductance L ₁, the first diode D ₁, the second diode D ₂, the second inductance L ₂, the first capacitor C ₁, switching tube S, the 3rd diode D ₃, the second capacitor C ₂, the 3rd inductance L ₃, the 3rd capacitor C ₃, the 4th diode D ₄, output capacitance C _out; Wherein, one end of described direct-current input power supplying and the first inductance L ₁one end connect, its other end respectively with the first capacitor C ₁one end, the drain electrode of switching tube S, the 3rd capacitor C ₃one end, output capacitance C _outone end of one end, load connect; Described the first inductance L ₁the other end respectively with the first diode D ₁anode and the second diode D ₂anodic bonding; Described the second inductance L ₂one end respectively with the first diode D ₁negative electrode, the drain electrode of switching tube S, the 3rd diode D ₃anode, the second capacitor C ₂one end connect, its other end respectively with the second diode D ₂negative electrode and the first capacitor C ₁the other end connect; Described the second capacitor C ₂the other end respectively with the 3rd inductance L ₃one end and the 4th diode D ₄anodic bonding; Described the 3rd diode D ₃negative electrode respectively with the 3rd inductance L ₃the other end and the 3rd capacitor C ₃the other end connect; Described the 4th diode D ₄negative electrode respectively with output capacitance C _outthe other end and the other end of load be connected; Described output capacitance C _outwith load parallel connection.

Shown in Figure 2, show the driving signal V of described switching tube S _g, the first inductance L ₁electric current I _l1, the second inductance L ₂electric current I _l2, the 3rd inductance L ₃electric current I _l3, output voltage V _o, the first capacitor C ₁voltage V _c1, the second capacitor C ₂voltage V _c2, the 3rd capacitor C ₃voltage V _c3at the waveform of a switch periods.

Shown in Fig. 3 a and Fig. 3 b, show the circuit mode in the utility model two stages in a switch periods, its concrete condition is as follows:

1) at t ₀～t ₁stage, as shown in Figure 3 a, the driving voltage V of switching tube S _gbecome high level from low level, switching tube S conducting, the first diode D ₁bear forward voltage conducting, DC input voitage V _inby the first diode D ₁give the first inductance L with switching tube S ₁charging; The second diode D ₂bear reverse voltage cut-off, the first capacitor C ₁give the second inductance L by switching tube S ₂charging; The 3rd diode D ₃bear reverse voltage cut-off, the 3rd capacitor C ₃give the 3rd inductance L by switching tube S ₃with the second capacitor C ₂charging; The 4th diode D ₄bear reverse voltage cut-off, output capacitance C _outpowering load.

2) at t ₁～t ₂stage, as shown in Figure 3 b, the driving voltage V of switching tube S _gbecome low level from high level, switching tube S turn-offs, the first diode D ₁bear reverse voltage cut-off, the second diode D ₂with the 3rd diode D ₃bear forward voltage conducting, DC input voitage V _inwith the first inductance L ₁give together the first capacitor C ₁charging; DC input voitage V _in, the first inductance L ₁with the second inductance L ₂give the 3rd capacitor C ₃charging; The 4th diode D ₄bear forward voltage conducting, DC input voitage V _in, the first inductance L ₁with the second inductance L ₂, the 3rd inductance L ₃with the second capacitor C ₂give output capacitance C _outcharging and load supplying.

Be below the steady state voltage gain situation of the above-mentioned single switch high gain boost DC/DC converter of the present embodiment:

Due to the first inductance L ₁voltage V _l1a switch periods mean value is zero, therefore can obtain as shown in the formula (1), obtains input voltage V by formula (1) _inwith the first capacitor C ₁voltage V _c1relational expression is as shown in the formula (2).

V _inD＝(V _C1-V _in)(1-D) （1）

$V_{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="HDA0000426861920000012.png,HDA0000426861920000031.png"\; state="\{\{state\}\}">C</figure-callout>}1}=\frac{1}{1-D}{V}_{\mathrm{in}}---\left(2\right)$

Due to the second inductance L ₂voltage V _l2a switch periods mean value is zero, therefore can obtain as shown in the formula (3), obtains the 3rd capacitor C by formula (3) ₃voltage V _c3with the first capacitor C ₁voltage V _c1relational expression is as shown in the formula (4).

V _C1D＝(V _C3-V _C1)(1-D) （3）

$V_{C3}=\frac{1}{1-D}{V}_{C1}---\left(4\right)$

Due to the 3rd inductance L ₃voltage V _l3a switch periods mean value is zero, therefore can obtain as shown in the formula (5), obtains the second capacitor C by formula (5) ₂voltage V _c2with the 3rd capacitor C ₃voltage V _c3relational expression is as shown in the formula (6).

(V _C3-V _C2)D＝V _C2(1-D) （5）

V _C2＝DV _C3 （6）

Due to output voltage V _oequal the second capacitor C ₂voltage V _c2with the 3rd capacitor C ₃voltage V _c3be added, so obtain DC input voitage V by formula (2), (4) and (6) _inwith output voltage V _orelational expression as shown in the formula (7).

$V_o={\mathrm{<figure-callout\; id="2"\; label="V\; C"\; filenames="HDA0000426861920000031.png"\; state="\{\{state\}\}">V</figure-callout>}}_C+V_{C3}=\frac{(1+D)}{1-\mathrm{<figure-callout\; id="1"\; label="D\; V\; C"\; filenames="HDA0000426861920000012.png,HDA0000426861920000031.png"\; state="\{\{state\}\}">D</figure-callout>}}{V}_C{1}_{}=\frac{(1+D)}{{(1-D)}^2}---\left(7\right)$

Conventionally, traditional single switch DC/DC converter, if the steady state voltage gain of BOOST, quadratic form BOOST converter is 1/ (1-D) and 1/ (1-D) ²(D is duty ratio).Shown in Figure 4, show the steady-state gain situation of the utility model and traditional B OOST and quadratic form BOOST converter, as we know from the figure, under the condition of identical duty ratio and input voltage, output voltage of the present utility model is higher than the output voltage of traditional B OOST and quadratic form BOOST converter.Therefore, than traditional single switch DC/DC converter, the utlity model has high steady state voltage gain, be applicable to the paramount direct voltage of low direct current voltage rise in grid-connected power generation system, realize the electrical connection of grid-connected power generation system and grid-connected system, be with a wide range of applications and very high promotional value.

The examples of implementation of the above are only the preferred embodiment of the utility model, not limit practical range of the present utility model with this, therefore the variation that all shapes according to the utility model, principle are done all should be encompassed in protection range of the present utility model.

Claims (1)

1. a single switch high gain boost DC/DC converter, is characterized in that: include direct-current input power supplying, the first inductance (L ₁), the first diode (D ₁), the second diode (D ₂), the second inductance (L ₂), the first electric capacity (C ₁), switching tube (S), the 3rd diode (D ₃), the second electric capacity (C ₂), the 3rd inductance (L ₃), the 3rd electric capacity (C ₃), the 4th diode (D ₄), output capacitance (C _out); Wherein, one end of described direct-current input power supplying and the first inductance (L ₁) one end connect, its other end respectively with the first electric capacity (C ₁) one end, the drain electrode of switching tube (S), the 3rd electric capacity (C ₃) one end, output capacitance (C _out) one end of one end, load connect; Described the first inductance (L ₁) the other end respectively with the first diode (D ₁) anode and the second diode (D ₂) anodic bonding; Described the second inductance (L ₂) one end respectively with the first diode (D ₁) negative electrode, the drain electrode of switching tube (S), the 3rd diode (D ₃) anode, the second electric capacity (C ₂) one end connect, its other end respectively with the second diode (D ₂) negative electrode and the first electric capacity (C ₁) the other end connect; Described the second electric capacity (C ₂) the other end respectively with the 3rd inductance (L ₃) one end and the 4th diode (D ₄) anodic bonding; Described the 3rd diode (D ₃) negative electrode respectively with the 3rd inductance (L ₃) the other end and the 3rd electric capacity (C ₃) the other end connect; Described the 4th diode (D ₄) negative electrode respectively with output capacitance (C _out) the other end and the other end of load be connected; Described output capacitance (C _out) and load parallel connection.

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