CN207399029U - A kind of converter circuit - Google Patents

A kind of converter circuit Download PDF

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Publication number
CN207399029U
CN207399029U CN201721448152.3U CN201721448152U CN207399029U CN 207399029 U CN207399029 U CN 207399029U CN 201721448152 U CN201721448152 U CN 201721448152U CN 207399029 U CN207399029 U CN 207399029U
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CN
China
Prior art keywords
auxiliary
change
switch
over switch
circuit
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Expired - Fee Related
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CN201721448152.3U
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Chinese (zh)
Inventor
洪俊杰
邓雪微
黄志恒
王得安
贾智海
梅汝华
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Guangdong University of Technology
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Guangdong University of Technology
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Abstract

The utility model discloses a kind of converter circuit, which includes:Switching capacity inductive switching circuit and the Zero voltage transition circuit being connected with switching capacity inductive switching circuit, Zero voltage transition circuit, before the change-over switch conducting in switching capacity inductive switching circuit, the operating voltage between the first end and second end of change-over switch is reduced to zero.The technical solution provided using the utility model embodiment, before change-over switch conducting, the operating voltage between change-over switch first end and second end can be caused to be reduced to zero, reduce change-over switch loss, extend the change-over switch service life, the electromagnetic interference in converter circuit can also be reduced.

Description

A kind of converter circuit
Technical field
The utility model is related to modern transformation of electrical energy technical field, more particularly to a kind of converter circuit.
Background technology
With the continuous development of Power Electronic Technique, semiconductor switch device has been made significant headway.
In recent years, switching capacity-inductive switching circuit extensive use in the converter.It please refers to Fig.2, the circuit first is straight Galvanic electricity source V1, the second DC power supply V2, the first diode D1, resonant inductance Lr, energy storage inductor L1, storage capacitor C1, change-over switch S, the second diode D2, filter capacitor Co and load resistance R, wherein, the first DC power supply V1Cathode, the second DC power supply V2 Cathode, the second end of change-over switch S, filter capacitor CoSecond end and the second end of load resistance R be connected to a node On, resonant inductance LrSecond end, storage capacitor C1First end and the second diode D2Anode connection on one node, Storage capacitor C1Second end, energy storage inductor L1Second end connected on one node with the first end of change-over switch S, second Diode D2Cathode, filter capacitor CoFirst end and the first end of load resistance R be connected on a node;One or two pole Pipe D1Anode and the first DC power supply V1Anode be connected, cathode and resonant inductance LrFirst end be connected;Energy storage electricity Feel L1First end and the second DC power supply V2Anode be connected.
It is existing, switching capacity-inductive switching circuit in application process, because of reasons such as circuit structures, conversion therein Switch is usually in the working condition of hard switching.With the raising of switching frequency, electromagnetic interference and switching loss in circuit Increase therewith.
In conclusion the problems such as electromagnetic interference and switching loss of the change-over switch how being effectively reduced in converter, It is the technical issues of current those skilled in the art are badly in need of solving.
Utility model content
The purpose of this utility model is to provide converter circuit, with reduce the electromagnetic interference of the change-over switch in converter and Switching loss.
In order to solve the above technical problems, the utility model provides following technical solution:
A kind of converter circuit, including:
Switching capacity-inductive switching circuit and the no-voltage being connected with the switching capacity-inductive switching circuit turn Circuit is changed, the Zero voltage transition circuit turns on it for the change-over switch in the switching capacity-inductive switching circuit Before, the operating voltage between the first end and second end of the change-over switch is reduced to zero.
Preferably, the Zero voltage transition circuit includes:
Auxiliary capacitor, auxiliary induction, fast recovery diode and auxiliary switch;
Wherein, the first end of the auxiliary capacitor is connected with the first end of the auxiliary induction, and the of the auxiliary capacitor Two ends are connected with the second end of the auxiliary switch, the second end of the auxiliary induction and the first end phase of the auxiliary switch Even, the anode of the fast recovery diode is connected with the second end of the auxiliary induction, the moon of the fast recovery diode Pole is connected with the cathode of the second diode of the switching capacity-inductive switching circuit, the auxiliary induction and the auxiliary electricity The common port of appearance is connected with the first end of the change-over switch, the common port of the auxiliary capacitor and the auxiliary switch with it is described The second end of change-over switch is connected.
Preferably, the change-over switch is NMOS switch pipe, and first end is drain electrode, and second end is source electrode.
Preferably, the auxiliary switch is NMOS switch pipe, and first end is drain electrode, and second end is source electrode.
Preferably, the fast recovery diode is Schottky diode.
Preferably, the conversion driving pulse of the change-over switch is identical with the frequency of the driving pulse of the auxiliary switch, And the duty cycle for converting driving pulse is N times of the driving pulse, wherein N is the positive number more than 1.
Preferably, in the case where the change-over switch and the auxiliary switch are in cut-off state, when the auxiliary is opened It closes after being turned under the action of the driving pulse, forms drop nulling loop, the nulling loop that drops is by the work of the change-over switch Voltage is reduced to zero.
Preferably, the voltage of the first DC power supply in the switching capacity-inductive switching circuit is greater than or equal to second The voltage of DC power supply.
The technical solution provided using the utility model embodiment, switching capacity-inductive switching circuit and with switch The Zero voltage transition circuit that capacitance-inductance conversion circuit is connected, Zero voltage transition circuit, for turning in switching capacity-inductance It changes before the change-over switch conducting in circuit, the operating voltage between the first end and second end of the change-over switch is reduced to Zero.Converter circuit provided by the utility model increases Zero voltage transition electricity on the basis of switching capacity-inductive switching circuit Road before change-over switch conducting, can cause the operating voltage between change-over switch first end and second end to be reduced to zero, reduce and turn Switching loss is changed, extends the change-over switch service life, the electromagnetic interference in converter circuit can also be reduced.
Description of the drawings
It in order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only It is some embodiments of the utility model, for those of ordinary skill in the art, in the premise not made the creative labor Under, it can also be obtained according to these attached drawings other attached drawings.
Fig. 1 is a kind of existing switching capacity-inductive switching circuit diagram;
Fig. 2 is a kind of converter circuit structure schematic diagram in the utility model embodiment;
Fig. 3 is a kind of converter circuit figure in the utility model embodiment;
Fig. 4 is the corresponding timing waveform of a kind of converter circuit in the utility model embodiment.
Specific embodiment
The core of the utility model is to provide a kind of converter circuit, which includes switching capacity-inductive switching circuit And the Zero voltage transition circuit being connected with switching capacity-inductive switching circuit, Zero voltage transition circuit, in switch electricity Before change-over switch conducting in appearance-inductive switching circuit, by the work between the first end and second end of the change-over switch Voltage is reduced to zero.Converter circuit provided by the utility model increases by zero electricity on the basis of switching capacity-inductive switching circuit Voltage conversion circuit before change-over switch conducting, can cause the operating voltage between change-over switch first end and second end to be reduced to Zero, change-over switch loss is reduced, extends the change-over switch service life, the electromagnetic interference in converter circuit can also be reduced.
In order to which those skilled in the art is made to more fully understand the utility model, below in conjunction with the accompanying drawings and it is embodied The utility model is described in further detail for mode.Obviously, described embodiment is only the utility model part Embodiment, instead of all the embodiments.Based on the embodiment in the utility model, those of ordinary skill in the art are not doing Go out all other embodiments obtained under the premise of creative work, shall fall within the protection scope of the present invention.
It please refers to Fig.1 and Fig. 2, converter circuit provided by the utility model includes:
Switching capacity-inductive switching circuit 101 and the no-voltage being connected with switching capacity-inductive switching circuit 101 Conversion circuit 102, Zero voltage transition circuit 102 turn on it for the change-over switch in switching capacity-inductive switching circuit Before, the operating voltage between the first end and second end of the change-over switch is reduced to zero.
In the present embodiment, the connection of switching capacity-between inductance converter circuit 101 and Zero voltage transition circuit 102 Relation refers to Fig. 1.It, can be during change-over switch S be turned on (in change-over switch S after increasing Zero Voltage Converter circuit 102 Before conducting), by the operating voltage V between the first end and second end of change-over switch SSIt is reduced to zero, you can so that conversion is opened Close the working condition being in Sofe Switch.In the other embodiment of the utility model, switching capacity-inductance converter circuit 101 specific circuit structures are referred to Fig. 2, that is to say, that the utility model embodiment provide converter circuit can be Based on adding acquired circuit after Zero Voltage Converter circuit 102 on the basis of circuit shown in Fig. 2.
Incorporated by reference to Fig. 3, in one embodiment of the utility model, Zero voltage transition circuit 102 can specifically be included such as Lower device and structure.
Auxiliary capacitor Cr, auxiliary induction Lr1, fast recovery diode DrWith auxiliary switch S1, wherein, auxiliary capacitor Cr One end and auxiliary induction Lr1First end be connected, auxiliary capacitor CrSecond end and auxiliary switch S1Second end be connected, aid in Inductance Lr1Second end and auxiliary switch S1First end be connected, fast recovery diode DrAnode and auxiliary induction Lr1 Two ends are connected, fast recovery diode DrCathode and switching capacity-inductive switching circuit 101 the second diode D2Cathode It is connected, auxiliary induction Lr1With auxiliary capacitor CrCommon port be connected with the first end of change-over switch S, auxiliary capacitor CrIt is opened with auxiliary Close S1Common port be connected with the second end of change-over switch S.
It should be noted that except change-over switch S and auxiliary switch S1Outside involved electronic device first end and Second end only for ease of the connection relation between outlines device, not limits its connectivity port and also just says for two connectivity ports Use can be converted.Such as load resistance R, the first end of load resistance can be any one in two connecting pins, After first end determines, second end can be also determined.For the description above on first end, second end, in accordance with following Principle:When electronic device traverse in Fig. 1 and/or Fig. 2, first end be the electronic device left side connecting pin, second Hold the right side connecting pin for the electronic device;When the electronic device is placed vertically, first end is the electronic device in vertical direction Upper connecting pin, second end for the electronic device in the lower connecting pin of vertical direction.
Wherein, change-over switch can be NMOS switch pipe, i.e. n-channel MOSFET switch pipe, and first end is drains, second It holds as source electrode.Auxiliary switch can be NMOS switch pipe, and first end is drain electrode, and second end is source electrode.
Certainly, in the other embodiment of the utility model, change-over switch S and auxiliary switch S1Can also be that other can Reach the switching tube of same technique effect, such as the high performance switching tube of igbt, PMOS tube.
Fast recovery diode DrCan be that Schottky diode or can reach does not influence the utility model and realizes invention The diode of other models of target.To ensure the normal work of conversion circuit, in switching capacity-inductive switching circuit 101 First DC power supply V1Voltage should be greater than or equal to the second DC power supply V2Voltage.
In one embodiment of the utility model, conversion driving pulse and the auxiliary switch S of change-over switch S1Driving The frequency of pulse can be identical, and, the duty cycle for converting driving pulse can also be N times of driving pulse, and wherein N is more than 1 Positive number, such as 3,6,7.
In one embodiment of the utility model, in change-over switch S and auxiliary switch S1Situation in cut-off state Under, as auxiliary switch S1After being turned under the action of driving pulse, drop nulling loop can be formed, drop nulling loop can open conversion The operating voltage for closing S is reduced to zero before conducting.When change-over switch S is turned on, auxiliary switch S1Under the action of driving pulse Cut-off.
In one of the utility model has embodiment, in practical applications, following parameter can refer to:
First DC power supply V1=30v, the second DC power supply V2=20v;Resonant inductance Lr=0.3uH;Storage capacitor C1= 4.7uF;Energy storage inductor L1=30uH;Filter capacitor Co=100uF;Load resistance R=45 Ω;Change-over switch S is switch mosfet Pipe converts frequency fs=100kHZ, the duty cycle d=0.6 of driving pulse;Auxiliary capacitor Cr=10nF;Auxiliary induction Lr1= 15uF;Auxiliary switch S1For switch mosfet pipe, frequency fs=100kHZ, the duty cycle d=0.1 of driving pulse.
The technical solution provided using the utility model embodiment, switching capacity-inductive switching circuit and with switch The Zero voltage transition circuit that capacitance-inductance conversion circuit is connected, Zero voltage transition circuit, for turning in switching capacity-inductance It changes before the change-over switch conducting in circuit, the operating voltage between the first end and second end of the change-over switch is reduced to Zero.Converter circuit provided by the utility model increases Zero voltage transition electricity on the basis of switching capacity-inductive switching circuit Road before change-over switch conducting, can cause the operating voltage between change-over switch first end and second end to be reduced to zero, reduce and turn Switching loss is changed, extends the change-over switch service life, the electromagnetic interference in converter circuit can also be reduced.
The technical solution that the utility model embodiment is provided for ease of understanding, with reference to Fig. 3 and Fig. 4, to this practicality The conversion circuit that new embodiment is provided is illustrated.It should be noted that for the ease of analysis, for shown in Fig. 3 Circuit, it is assumed that all elements ignore the conduction voltage drop of switching tube, ignore diode, switching tube cut-off all in perfect condition When drain current, ignore the series resistance of capacitance, flow through L1Electric current it is continuous, CoOutput electricity on enough ambassador's load resistance R It presses constant.
As shown in figure 4, wherein t0-t7For the waveform situation of change in a complete cycle, below mainly to this seven works It is analyzed as state.Assuming that in t0Before, the original state of conversion circuit is:Change-over switch S, auxiliary switch S1All in cut Only state, wherein, V2-L1-C1-D2- R series circuits are powered to load resistance R, and form boosting circuit, flow through the electricity in the circuit It flows for iD2.
(1)t0-t1Period
In t0Moment, auxiliary switch S1It is turned under the action of driving pulse Vgs1.V2-L1-Lr1-S1Circuit is formed, is flowed through The electric current ir1 in the circuit is linearly increased, in t1Moment, the value of electric current ir1 are equal to electric current iD2 in t0The value at moment.Flow through circuit V2-L1-C1-D2The electric current iD2 of-R linearly reduces, in t1Moment is reduced to zero, D2Cut-off.
(2)t1-t2Period
Cr-Lr1-S1Resonant tank is formed, flows through auxiliary induction Lr1Electric current ir1 in sinusoidal increase auxiliary capacitor CrOn Voltage reduce, in t2Moment, auxiliary capacitor CrOn voltage when being reduced to zero, the electric current ir1 of auxiliary induction Lr1 reaches maximum Value.Because change-over switch S and auxiliary induction CrParallel connection, so in t2Moment, the operating voltage V at change-over switch S both endssAlso it is zero.
(3)t2-t3Period
In this period, auxiliary switch S1Continue to turn on, flow through auxiliary induction Lr1Electric current ir1 be maintained at maximum, turn Change the operating voltage V at switch S both endssIt still keeps also being zero.
(4)t3-t4Period
In t3Moment, change-over switch S are turned under the action of driving pulse Vgs is converted, auxiliary switch S1In driving pulse End under the action of Vgs1.Due to change-over switch S before conducting operating voltage VsZero is reduced to, so change-over switch S is real No-voltage conducting is showed, the realization of no-voltage conducting compared with prior art reduces switching loss, reduces switch noise.At this moment Between three circuits are formed in section:V1-D1-Lr-C1- S forms the first DC power supply of resonant tank V1To storage capacitor C1It charges, resonance Inductance LrOn iLr electric currents be in sinusoidal variations;V2-L1Second DC power supply V in-S circuits2To energy storage inductor L1It charges, energy storage electricity Feel L1On iL1 electric currents linearly increase;S-Lr1-DrAuxiliary induction L in-R circuitsr1On electric current iLr1 be in since maximum It is linear to reduce, in t4Moment flows through auxiliary induction Lr1On electric current ir1 be reduced to zero, fast recovery diode DrCut-off.
(5)t4-t5Period
In V1-D1-Lr-C1In-S resonant tanks, the first DC power supply V1Continue to energy storage inductor C1It is charged to t5Moment electricity Stream ir1 is reduced to zero, the first diode D1Cut-off, storage capacitor C1Charging terminates, at this time storage capacitor C1Upper voltage reaches maximum Value;V2-L1- S circuits are always maintained at the second DC power supply V in this period2To energy storage inductor L1It charges, flows through energy storage inductor L1On IL1 electric currents still linearly increase.
(6)t5-t6Period
Within this period, only surplus V2-L1- S circuits, the second DC power supply V2Continue to energy storage inductor L1It charges.To t6Moment, Change-over switch S ends, energy storage inductor L1Charging terminates, and flows through energy storage inductor L1Upper electric current reaches maximum.
(7)t6-t7Period
Change-over switch S and auxiliary switch S1All end, at this point, V2-L1-CrCircuit is formed to auxiliary capacitor CrIt charges, t7When The operating voltage for carving change-over switch S reaches maximum;V simultaneously2-L1-C1-D2- R forms circuit and discharges to load resistance R, negative It carries resistance R and obtains higher output voltage.
The utility model, by introducing soft switch technique, allows original on the basis of existing switching capacity-inductance converter Change-over switch is under work Sofe Switch state and works.Auxiliary capacitor C in the Zero voltage transition circuit being introduced intorWith change-over switch S parallel connections limit the climbing for flowing through change-over switch electric current.At the same time, Zero voltage transition circuit is only operated in change-over switch S Very short a period of time before conducting, flow through auxiliary switch S1Electric current virtual value it is smaller, and auxiliary switch S1It is zero current Conducting, so as to reduce switching loss.Its circuit of the conversion of the utility model is also equipped with that topological structure is simple, small, quality Gently, it is at low cost, be easy to operate and control, suitable for middle low power high frequency occasion the advantages that.
A kind of converter circuit provided by the utility model is described in detail above.Each implementation in specification Example is described by the way of progressive, the highlights of each of the examples are difference from other examples, each implementation Just to refer each other for identical similar portion between example.It should be pointed out that for those skilled in the art, not Depart from the utility model principle on the premise of, can also to the utility model, some improvement and modification can also be carried out, these improve and repair Decorations are also fallen into the protection domain of the utility model claims.

Claims (8)

1. a kind of converter circuit, which is characterized in that including:
Switching capacity-inductive switching circuit and the Zero voltage transition electricity being connected with the switching capacity-inductive switching circuit Road, the Zero voltage transition circuit, will before the change-over switch conducting in the switching capacity-inductive switching circuit Operating voltage between the first end and second end of the change-over switch is reduced to zero.
2. converter circuit according to claim 1, which is characterized in that the Zero voltage transition circuit includes:
Auxiliary capacitor, auxiliary induction, fast recovery diode and auxiliary switch;
Wherein, the first end of the auxiliary capacitor is connected with the first end of the auxiliary induction, the second end of the auxiliary capacitor It is connected with the second end of the auxiliary switch, the second end of the auxiliary induction is connected with the first end of the auxiliary switch, institute The anode for stating fast recovery diode is connected with the second end of the auxiliary induction, the cathode of the fast recovery diode and institute The cathode for stating the second diode of switching capacity-inductive switching circuit is connected, the public affairs of the auxiliary induction and the auxiliary capacitor End is connected with the first end of the change-over switch altogether, and the common port of the auxiliary capacitor and the auxiliary switch is opened with the conversion The second end of pass is connected.
3. converter circuit according to claim 1, which is characterized in that the change-over switch is NMOS switch pipe, the One end is drain electrode, and second end is source electrode.
4. converter circuit according to claim 2, which is characterized in that the auxiliary switch is NMOS switch pipe, the One end is drain electrode, and second end is source electrode.
5. converter circuit according to claim 4, which is characterized in that the fast recovery diode is two pole of Schottky Pipe.
6. converter circuit according to claim 5, which is characterized in that the conversion driving pulse of the change-over switch and institute It is identical to state the frequency of the driving pulse of auxiliary switch, and, the duty cycle for converting driving pulse into the driving pulse N Times, wherein N is the positive number more than 1.
7. converter circuit according to claim 6, which is characterized in that at the change-over switch and the auxiliary switch In the case of cut-off state, when the auxiliary switch under the action of the driving pulse after turning on, nulling loop, institute drop in formation It states drop nulling loop and the operating voltage of the change-over switch is reduced to zero before conducting.
8. converter circuit according to claim 7, which is characterized in that in the switching capacity-inductive switching circuit The voltage of first DC power supply is greater than or equal to the voltage of the second DC power supply.
CN201721448152.3U 2017-11-01 2017-11-01 A kind of converter circuit Expired - Fee Related CN207399029U (en)

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Application Number Priority Date Filing Date Title
CN201721448152.3U CN207399029U (en) 2017-11-01 2017-11-01 A kind of converter circuit

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Application Number Priority Date Filing Date Title
CN201721448152.3U CN207399029U (en) 2017-11-01 2017-11-01 A kind of converter circuit

Publications (1)

Publication Number Publication Date
CN207399029U true CN207399029U (en) 2018-05-22

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107659141A (en) * 2017-11-01 2018-02-02 广东工业大学 A kind of converter circuit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107659141A (en) * 2017-11-01 2018-02-02 广东工业大学 A kind of converter circuit

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