CN205847091U - A kind of switched inductors type quasi-boost switching DC DC changer - Google Patents

Abstract

This utility model provides a kind of switched inductors type quasi-boost switching DC DC converter circuit, including voltage source, the switched inductors unit being made up of the first inductance, the second inductance, the 4th diode, the 5th diode and the 6th diode, the two ends quasi-boost switching unit being made up of the first electric capacity, the first diode, the first metal-oxide-semiconductor, the 3rd diode and switched inductors unit, second metal-oxide-semiconductor, second electric capacity, the second diode, output diode, output filter capacitor and load.Whole circuit structure is simple, combines quasi-boost switching unit, switching capacity unit and switched inductors unit respective single-stage boosting characteristic, it is achieved that the expansion of output voltage gain.

Description

A kind of switched inductors type quasi-boost switching DC-DC converter

Technical field

This utility model relates to Power Electronic Circuit technical field, is specifically related to a kind of quasi-boost switching of switched inductors type DC-DC converter circuit.

Background technology

In fuel cell power generation, photovoltaic generation, due to single solaode or single fuel cell provide straight Stream voltage is relatively low, it is impossible to meets the need for electricity of existing electrical equipment, can not meet grid-connected demand, generally requires multiple Battery is together in series the voltage reaching required.On the one hand this method greatly reduces the reliability of whole system, on the other hand Also need to solve series average-voltage problem.For this reason, it may be necessary to can be high-tension high-gain DC-DC converter low voltage transition.Closely The switching boost converter SBI proposed for several years is little due to the excursion of its output voltage, exports at low-voltage high input voltage Occasion, such as distributed energy grid-connected system and fuel cell system, tradition SBI changer becomes no longer to be suitable for.In order to expand The scope of application of tradition SBI changer, it is necessary to improved by topology and expand its output voltage gain.

Utility model content

The purpose of this utility model is to overcome above-mentioned the deficiencies in the prior art, it is provided that a kind of switched inductors type quasi-switch Boost DC-DC converter circuit, concrete technical scheme is as follows.

A kind of switched inductors type quasi-boost switching DC-DC converter circuit, including voltage source, by the first inductance, the second electricity Sense, the 4th diode, the switched inductors unit that the 5th diode and the 6th diode are constituted, by the first electric capacity, the first diode, The two ends quasi-boost switching unit that first metal-oxide-semiconductor, the 3rd diode and switched inductors unit are constituted, the second metal-oxide-semiconductor, the second electricity Holding, the second diode, output diode, output filter capacitor and load are constituted.

In above-mentioned a kind of switched inductors type quasi-boost switching DC-DC converter circuit, the positive pole of described voltage source is respectively It is connected with the negative pole of the first electric capacity and the anode of the 3rd diode；The positive pole of described first electric capacity respectively with the moon of the first diode The anode of pole, the drain electrode of the first metal-oxide-semiconductor and output diode connects；The source electrode of described first metal-oxide-semiconductor respectively with the 3rd diode Negative electrode, one end of the first inductance and the 4th diode anode connect；The negative electrode of described 4th diode is respectively with the five or two The negative electrode of pole pipe and one end of the second inductance connect；The other end of described first inductance respectively with the anode and of the 5th diode The anode of six diodes connects；The anode of described first diode respectively with the other end, the leakage of the second metal-oxide-semiconductor of the second inductance The negative electrode of pole, the positive pole of the second electric capacity and the 6th diode connects；The negative pole of described second electric capacity respectively with the second diode One end of anode, the negative pole of output filter capacitor and load connects；The negative electrode of described output diode respectively with output filtered electrical The positive pole held and the other end of load connect；The negative pole of described voltage source respectively with the source electrode of the second metal-oxide-semiconductor, the second diode Negative electrode connects.

Compared with prior art, this utility model circuit has the advantage that and technique effect: the whole electricity of this utility model Line structure is simple, and easy to control, output voltage gain is higher；This utility model circuit utilizes the single-stage liter of quasi-boost switching unit Dropping voltage characteristic and switched inductors and switching capacity charge the characteristic of discharged in series parallel, thus increase output voltage, it is achieved The expansion of quasi-switching boost converter output voltage gain.

Accompanying drawing explanation

Fig. 1 is a kind of switched inductors type quasi-boost switching DC-DC converter electricity in this utility model detailed description of the invention Road.

Fig. 2 a, Fig. 2 b be a kind of switched inductors type quasi-boost switching DC-DC converter circuit shown in Fig. 1 respectively its first Metal-oxide-semiconductor and the second metal-oxide-semiconductor simultaneously turn on and simultaneously turn off the equivalent circuit diagram of period.

Fig. 3 is gain curve and Boost, switching capacity Boost, the traditional Z of this utility model circuit Source DC-DC converter and the gain curve comparison diagram of novel quasi-Z source DC-DC converter.

Detailed description of the invention

The technical solution of the utility model is explained in detail by above content, new to this practicality below in conjunction with accompanying drawing Being embodied as of type is further described.

With reference to Fig. 1, a kind of switched inductors type quasi-boost switching DC-DC converter circuit described in the utility model, including Voltage source, the switched inductors list being made up of the first inductance, the second inductance, the 4th diode, the 5th diode and the 6th diode Unit, the two end quasi-switches being made up of the first electric capacity, the first diode, the first metal-oxide-semiconductor, the 3rd diode and switched inductors unit rise Pressure unit, the second metal-oxide-semiconductor, the second electric capacity, the second diode, output diode D_o, output filter capacitor and load R_L.When first Metal-oxide-semiconductor S₁With the second metal-oxide-semiconductor S₂When simultaneously turning on, described first diode D₁, the second diode D₂, the 3rd diode D₃With the 5th Diode D₅It is turned off, the 4th diode D₄, the 6th diode D₆Conducting；Described voltage source V_iWith the first electric capacity C₁Together to parallel connection The first inductance L₁With the second inductance L₂Charging energy-storing；Meanwhile, voltage source V_i, the first electric capacity C₁With the second electric capacity C₂Together to output Filter capacitor C_fWith load R_LPower supply.As the first metal-oxide-semiconductor S₁With the second metal-oxide-semiconductor S₂When simultaneously turning off, described first diode D₁, Two diode D₂, the 3rd diode D₃With the 5th diode D₅It is both turned on, the 4th diode D₄, the 6th diode D₆With export two poles Pipe D_oTurn off；First inductance L₁With the second inductance L₂With the first electric capacity C after series connection₁Parallel connection, forms loop；Described voltage source V_iWith One inductance L₁With the second inductance L₂Together to the second electric capacity C₂Charging, forms loop；Meanwhile, output filter capacitor C_fTo load R_LEnter Row power supply.Whole circuit structure is simple, has higher output voltage gain.

The concrete connected mode of this utility model circuit is as follows: the positive pole of described voltage source respectively with the negative pole of the first electric capacity Connect with the anode of the 3rd diode；The positive pole of described first electric capacity respectively with negative electrode, the leakage of the first metal-oxide-semiconductor of the first diode The anode of pole and output diode connects；The source electrode of described first metal-oxide-semiconductor respectively with the negative electrode of the 3rd diode, the first inductance The anode of one end and the 4th diode connects；The negative electrode of described 4th diode is electric with the negative electrode of the 5th diode and second respectively One end of sense connects；The other end of described first inductance connects with the anode of the 5th diode and the anode of the 6th diode respectively Connect；The anode of described first diode respectively with the other end of the second inductance, the drain electrode of the second metal-oxide-semiconductor, the positive pole of the second electric capacity Connect with the negative electrode of the 6th diode；The negative pole of described second electric capacity respectively with anode, the output filter capacitor of the second diode Negative pole and load one end connect；The negative electrode of described output diode another with the positive pole of output filter capacitor and load respectively One end connects；The negative pole of described voltage source is connected with source electrode, the negative electrode of the second diode of the second metal-oxide-semiconductor respectively.

Fig. 2 a, Fig. 2 b give the process chart of this utility model circuit.Fig. 2 a, Fig. 2 b correspondence respectively is first Metal-oxide-semiconductor S₁With the second metal-oxide-semiconductor S₂Simultaneously turn on and simultaneously turn off the equivalent circuit diagram of period.Have during in figure, solid line represents changer The part that electric current flows through, dotted line represents the part that in changer, no current flows through.

Work process of the present utility model is as follows:

Stage 1, such as Fig. 2 a: the first metal-oxide-semiconductor S₁With the second metal-oxide-semiconductor S₂Simultaneously turn on, now the first diode D₁, the two or two Pole pipe D₂, the 3rd diode D₃With the 5th diode D₅It is turned off, the 4th diode D₄, the 6th diode D₆Conducting.Circuit is formed Two loops, respectively: voltage source V_iWith the first electric capacity C₁With the second electric capacity C₂Give output filter capacitor C together_fWith load R_L Charging, forms loop；Voltage source V_iWith the first electric capacity C₁To the first inductance L in parallel₁With the second inductance L₂It is charged energy storage, Form loop.

Stage 2, such as Fig. 2 the b: the first metal-oxide-semiconductor S₁With the second metal-oxide-semiconductor S₂Simultaneously turn off, now the first diode D₁, the two or two Pole pipe D₂, the 3rd diode D₃With the 5th diode D₅It is both turned on, the 4th diode D₄, the 6th diode D₆With output diode D_o Turn off.Circuit defines three loops, respectively: voltage source V_iWith the first inductance L₁With the second inductance L₂Give the second electric capacity together C₂Charging energy-storing, forms loop；First inductance L₁With the second inductance L₂Together to the first electric capacity C after series connection₁Charging, forms loop； Output filter capacitor C_fGive load R_LPower supply, forms loop.

To sum up situation, due to the first metal-oxide-semiconductor S₁With the second metal-oxide-semiconductor S₂Switch triggering pulse identical, if switching tube S₁ And S₂Dutycycle be D, switch periods is T_s.And set V_L1And V_L2It is respectively the first inductance L₁With the second inductance L₂Two ends Voltage, V_C1、V_C2It is respectively the first electric capacity C₁With the second electric capacity C₂Voltage, V_S1For and V_S2It is respectively the first metal-oxide-semiconductor S₁With second Metal-oxide-semiconductor S₂Voltage between drain electrode and source electrode.Switch periods T_sIn, making output voltage is V_o.When changer enters stable state After work, draw following voltage relationship derivation.

Operation mode 1: the first metal-oxide-semiconductor S₁With the second metal-oxide-semiconductor S₂Simultaneously turn on, shown in corresponding equivalent circuit diagram 2a, therefore There is an equation below:

V_{L1_on}=V_{L2_on}=V_i+V_C1 (1)

V_O=V_i+V_C1+V_C2 (2)

V_S1=V_S2=0 (3)

Metal-oxide-semiconductor S₁And S₂ON time be DT_s。

Operation mode 2: the first metal-oxide-semiconductor S₁With the second metal-oxide-semiconductor S₂Be turned off, corresponding equivalent circuit as shown in Figure 2 b, therefore There is an equation below:

V_{L1_off}+V_{L2_off}=-V_C1

(4)

V_{L1_off}+V_{L2_off}=V_i-V_C2 (5)

V_S2=V_C2 (6)

V_S1=V_C1 (7)

Metal-oxide-semiconductor S₁And S₂Turn-off time be (1-D) T_s。

Analyze according to above, the first inductance L1 and the second inductance L2 is used inductance Flux consumption conservation principle, simultaneous respectively Formula (1), formula (4), formula (5) can obtain:

D(V_i+V_C1)-(1-D)(V_C1+V_{L2_off})=0 (8)

D(V_i+V_C1)-(1-D)(V_C1+V_{L1_off})=0 (9)

Simultaneous formula (8) and formula (9) can be tried to achieve:

$V_{L1\_off}=V_{L2\_off}=-\frac{V_{C1}}{2}---\left(10\right)$

Thus, simultaneous formula (8), formula (9) and formula (10) can draw the first electric capacity C₁Voltage V_C1, the second electric capacity C₂Voltage V_C2With voltage source V_iBetween relational expression be:

$V_{C1}=\frac{2D}{1-3D}{V}_i---\left(11\right)$

$V_{C2}=\frac{1-D}{1-3D}{V}_i---\left(12\right)$

Then by formula (2), formula (11) and formula (12), the output voltage V of this utility model circuit can be obtained_oExpression formula is:

$V_o=\frac{2(1-D)}{1-3D}{V}_i---\left(13\right)$

Then the expression formula of the output voltage gain of this utility model circuit is:

$G=\frac{V_o}{V_i}=\frac{2(1-D)}{1-3D}---\left(14\right)$

Be illustrated in figure 3 the gain curve of this utility model circuit and Boost, switching capacity Boost, Traditional Z source DC-DC converter and the gain curve comparison diagram of novel quasi-Z source DC-DC converter, figure includes this utility model electricity The gain curve on road, the gain curve of novel quasi-Z source DC-DC converter, the gain curve of traditional Z source DC-DC converter, switch The gain curve of electric capacity Boost, and the gain curve of Boost.As seen from the figure, this utility model circuit is accounting for Empty than D less than 0.33 in the case of, gain G just can reach very greatly, and dutycycle D of this utility model circuit not over 0.33.Therefore, by contrast, the gain of this utility model circuit is the highest.

In sum, this utility model circuit overall structure is simple, easy to control, combines quasi-boost switching unit single-stage The characteristic of buck and switched inductors and switching capacity are charged the characteristic of discharged in series parallel, it is achieved that output voltage gain Promote further, and there is not inrush current and metal-oxide-semiconductor opens the dash current of moment.

Above-described embodiment is this utility model preferably embodiment, but embodiment of the present utility model is not by described The restriction of embodiment, other any without departing from the change made under spirit of the present utility model and principle, modify, replace In generation, combine, simplify, all should be the substitute mode of equivalence, within being included in protection domain of the present utility model.

Claims (1)

1. a switched inductors type quasi-boost switching DC-DC converter circuit, it is characterised in that include voltage source (V_i), switch electricity Sense unit, quasi-boost switching unit, the second metal-oxide-semiconductor (S₂), the second electric capacity (C₂) the second diode (D₂), output diode (D_o), Output filter capacitor (C_f) and load (R_L)；Described switched inductors unit is by the first inductance (L₁), the second inductance (L₂), the four or two Pole pipe (D₄), the 5th diode (D₅), the 6th diode (D₆) constitute；Described quasi-boost switching unit is by the first diode (D₁), First electric capacity (C₁), the first metal-oxide-semiconductor (S₁), the 3rd diode (D₃) and foregoing switched inductors unit composition；

Described voltage source (V_i) positive pole respectively with the first electric capacity (C₁) negative pole and the 3rd diode (D₃) anode connect；Institute State the first electric capacity (C₁) positive pole respectively with the first diode (D₁) negative electrode, the first metal-oxide-semiconductor (S₁) drain electrode and output diode (D_o) anode connect；Described first metal-oxide-semiconductor (S₁) source electrode respectively with the 3rd diode (D₃) negative electrode, the first inductance (L₁) One end and the 4th diode (D₄) anode connect；Described 4th diode (D₄) negative electrode respectively with the 5th diode (D₅) Negative electrode and the second inductance (L₂) one end connect；Described first inductance (L₁) the other end respectively with the 5th diode (D₅) Anode and the 6th diode (D₆) anode connect；Described first diode (D₁) anode respectively with the second inductance (L₂) another One end, the second metal-oxide-semiconductor (S₂) drain electrode, the second electric capacity (C₂) positive pole and the 6th diode (D₆) negative electrode connect；Described second Electric capacity (C₂) negative pole respectively with the second diode (D₂) anode, output filter capacitor (C_f) negative pole and load (R_L) one End connects；Described output diode (D_o) negative electrode respectively with output filter capacitor (C_f) positive pole and load (R_L) the other end Connect；Described voltage source (V_i) negative pole respectively with the second metal-oxide-semiconductor (S₂) source electrode, the second diode (D₂) negative electrode connect.