CN106411106A - Passive soft switching full-bridge conversion circuit and method suitable for fixed frequency - Google Patents
Passive soft switching full-bridge conversion circuit and method suitable for fixed frequency Download PDFInfo
- Publication number
- CN106411106A CN106411106A CN201610480476.9A CN201610480476A CN106411106A CN 106411106 A CN106411106 A CN 106411106A CN 201610480476 A CN201610480476 A CN 201610480476A CN 106411106 A CN106411106 A CN 106411106A
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- Prior art keywords
- power switch
- absorption
- switch pipe
- full
- bridge type
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0048—Circuits or arrangements for reducing losses
- H02M1/0054—Transistor switching losses
- H02M1/0058—Transistor switching losses by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Abstract
The invention belongs to the field of power electronics branches, and particularly relates to a passive soft switching full-bridge conversion circuit and method suitable for a fixed frequency. The target of zero current turn-on of power switch tubes is achieved by using two buffer inductors which are connected between the upper power switch tubes and the lower power switch tubes of main bridge arms at two sides in series. The target of zero voltage turn-off of the power switch tubes is achieved by using two absorption capacitors which are connected with a lower bridge arm in parallel. Resetting of the absorption capacitors is finished by using two fast diodes connected to each absorption capacitor and a current-limiting inductor and the effect of inhibiting surge current is achieved. According to the passive soft switching full-bridge conversion circuit and method suitable for the fixed frequency, relatively few energy exchange circuits and transfer circuits, a relatively low loss and a relatively high buffer effect can be achieved at a simple topology and relatively low cost.
Description
Technical field
The invention belongs to power electronics branch field, more particularly, to it is applied to the passive flexible switch full-bridge type conversion of fixed frequency
Circuit and method.
Background technology
One principal element of impact switch power efficiency, is the switching loss of power switch pipe.Power attenuation can use following formula table
State：P=U × I.
It will be seen from figure 1 that during t0～t1, t3～t5, the electric current due to flowing through power switch pipe is zero (to ignore
Power switch tube leakage current), the loss of power switch pipe is zero,；During t2～t3, t6～t7, due to being applied to
The voltage of power switch pipe was zero (ignoring power switch pipe conducting resistance), and the loss of power switch pipe is zero；And t1～
T2, t3～t4, t5～t6, t7～t8 power switch pipe switch transition period, it is applied to voltage on power switch pipe, electricity
Stream is all not zero, and produces power switch pipe switching loss therefrom, in voltage, electric current intersection, produces transient state maximum power dissipation.
In order to overcome the defect of hard-switching converter it is proposed that many soft-switching process.These soft-switching process can be divided into two
Big class.One class is active soft switching technology, typical as PWM no-voltage or zero point pretreatment soft switch technique, they be with
Additional auxiliary active switch and LC resonant element, make power switch pipe complete transitive state under no-voltage or under zero current
The change of current of period；Its essence is to make use of LC resonance circuit to there is in real time may be used of voltage or current over-zero state and active switch
Control property, to realize Sofe Switch.But, resonant energy here must sufficiently large to create zero voltage switching or zero current switching
Condition, in addition active resonance circuit should work under the control signal of Sofe Switch controller.Actually auxiliary circuit from
Body power consumption, and active device also brings the raising of cost and the reduction of reliability with the complexity controlling, therefore many soft is opened
The popularization and application of pass technology are limited by very large.Another kind is then passive flexible switch technology, and it is opened using main circuit power
The change closing pipe PWM state, to replace the auxiliary active switch by given sequencing contro, is only managed with passive and nondestructive components and parts
Passive snubber type soft switch circuit is constituted on hard-switching converter, due to without extra active switch and corresponding control,
Detection, drive circuit, just have relatively low cost, higher reliability, preferable cost performance, but also may obtain close
Increasingly obtain the attention of people in the effect of active soft switching technology.
However, at present in addition to the full-bridge passive flexible switch changer of special phase-shift PWM controlled, to most with tradition
PWM is the full-bridge converter of control method, and passive flexible switch technology still fails practical and becomes defect.Phase-shift PWM control
System also has the not equal defect of control circuit complexity, four device for power switching working conditions and suffered electric stress.
Content of the invention
It is an object of the present invention to provide a kind of passive flexible switch full-bridge type translation circuit being applied to fixed frequency and method, with succinct
Topological, relatively low cost, you can reach less energy exchange and transmission loop, relatively low loss, stronger buffering effect
Really.
For solving above-mentioned technical problem, the technical solution adopted in the present invention is：
It is applied to the passive flexible switch full-bridge type translation circuit of fixed frequency, including hard switching full-bridge type translation circuit, described hard
Switch full formula translation circuit includes exporting transformator, left arm path and right arm path；Described left arm path and You Qiao
Arm branch road all includes power switch pipe, lower power switch pipe；Described output transformator is connected to two lower power switch pipes
Between drain electrode；It is characterized in that：Also include buffer cell, absorptive unit, compensating unit；Described buffer cell includes point
It is not serially connected in the left buffer inductance between power switch pipe and lower power switch pipe and right buffer inductance；Described absorptive unit bag
Include left absorption branch road and right absorption branch road, described left absorption branch road and right absorption branch road all include absorption diode, absorption inductor
And Absorption Capacitance；The positive pole of described absorption diode is connected with the drain electrode of lower power switch pipe, its negative pole and the one of absorption inductor
End is connected；The other end of described absorption inductor is connected with one end of Absorption Capacitance；The other end of described Absorption Capacitance and lower power
The source electrode of switching tube is connected；Described compensating unit includes left compensation diode and right compensation diode；Described left compensation diode
Positive pole be connected with one end of Absorption Capacitance, its negative pole is connected with the source electrode of upper power switch pipe；Described right compensation diode
Positive pole is connected with one end of Absorption Capacitance, and its negative pole is connected with the source electrode of upper power switch pipe.
Above-mentioned absorption diode is high speed fast recovery diode.
Above-mentioned Absorption Capacitance is the noninductive absorption capacitor of high frequency.
It is applied to the passive flexible switch full-bridge type alternative approach of fixed frequency, hard switching full-bridge type translation circuit is controlled using PWM
Conducting；Comprise the following steps：
1) when the corresponding power switching tube that PWM controls is opened, make the electric current of main brachium pontis pass through a buffer inductance, realize
Zero current turning-on；
2), after this power switch pipe is opened, hard switching full-bridge type translation circuit works；
3) when this power switch pipe is closed, with being connected in parallel on the Absorption Capacitance of lower brachium pontis power switch pipe, realize no-voltage and close；
4), before this power switch pipe is opened to next time after closing, the electric energy of Absorption Capacitance is passed through to compensate diode feed-in power supply
In, realize the lossless reset of Absorption Capacitance.
For surge current suppression, also in step 1 the charging current of Absorption Capacitance can be passed through a buffer inductance.
The invention has the beneficial effects as follows：
1st, the present invention is serially connected in the buffer inductance in the middle of the upper and lower power switch pipe of the main brachium pontis in both sides using two, reaches work(
The purpose of rate switching tube zero current turning-on.
2nd, the present invention, using two Absorption Capacitances being attempted by lower brachium pontis, reaches the purpose of power switch pipe no-voltage closing.
3rd, the present invention, using two fast diodes being connected on each Absorption Capacitance, a current-limiting inductance, completes to absorb
The reset of electric capacity, and realize the effect of surge current suppression.
4th, the present invention is with succinct topological, relatively low cost, you can reach less energy exchange and transmission loop, relatively low
Loss, stronger buffering effect.
Brief description
Fig. 1 is the circuit theory diagrams of existing hard-switching converter；
Fig. 2 is existing hard-switching converter drive waveforms, voltage waveform, the schematic diagram of current waveform；
Fig. 3 is the circuit theory diagrams of the present invention；
Fig. 4 is the schematic diagram of drive waveforms of the present invention, voltage waveform, current waveform.
Specific embodiment
A kind of passive flexible switch full-bridge type translation circuit being applied to fixed frequency, including hard switching full-bridge type translation circuit and
It is serially connected in two buffer inductances in the middle of the upper and lower power switch pipe of the main brachium pontis in both sides, output transformator is connected to two lower bridges
The drain electrode of arm power switch pipe, absorbs the drain electrode that bypass diodes are also connected to two lower brachium pontis power switch pipes, Absorption Capacitance
It is connected with respective diode by buffer inductance, Absorption Capacitance compensates diode by two simultaneously and opens with two upper brachium pontis power
The source electrode closing pipe is connected.Absorption diode is High Speed Nanometer fast recovery diode.Absorption Capacitance is the noninductive Absorption Capacitance of high frequency
Device.
It is applied to the passive flexible switch full-bridge type alternative approach of fixed frequency, hard switching full-bridge type translation circuit is controlled using PWM
Conducting；This turn on process comprises the following steps：
1) when the corresponding power switching tube that PWM controls is opened, make the electric current of main brachium pontis pass through a buffer inductance, realize
Zero current turning-on；The charging current of Absorption Capacitance is passed through a buffer inductance simultaneously, realize the suppression of surge current；
2), after this power switch pipe is opened, hard switching full-bridge type translation circuit works；
3) when this power switch pipe is closed, with being connected in parallel on the Absorption Capacitance of lower brachium pontis power switch pipe, realize no-voltage and close；
4) before this power switch pipe is opened to next time after closing, using quick two poles of two being connected on each Absorption Capacitance
Pipe, a current-limiting inductance, complete the reset of Absorption Capacitance.Specifically, D2 ensures that discharge current can only flow to D1, D1
Ensure that charging current flows to power supply VP, LS3 is used for surge current suppression.
The principle of the invention：
The present invention is on the basis of traditional hard switching full-bridge converter, add two sets by two high speed fast recovery diodes,
The passive flexible switch network of the uniqueness that one high frequency is noninductive absorption capacitor, two buffer inductances are constituted.
Two buffer inductances in passive network are serially connected in the middle of the upper and lower power switch pipe of the main brachium pontis in both sides, export transformator
It is connected to the drain electrode of two lower brachium pontis power switch pipes, absorb bypass diodes and be also connected to two lower brachium pontis power switch pipes
Drain electrode, Absorption Capacitance is connected with respective diode by buffer inductance, and it is same that this Absorption Capacitance compensates diode by two simultaneously
The source electrode of two upper brachium pontis power switch pipes is connected.Therefore this network can make hard switching half bridge converter obtain passive soft open
Close effect.
From unlike other soft switch techniques, this passive flexible switch network, is with using energy storage inductor and electric capacity for invention
Form, the power switch tube voltage that staggers, electric current occur time and reach the target realizing power switch pipe Sofe Switch.Relatively
Low cost, less energy transmission loop, relatively low loss, under stronger buffering effect, hard switching full-bridge type is made to convert
Device obtains the effect of passive flexible switch.This new method can be directly applied to the full-bridge converter of fixed frequency.
Work process of the present invention：
From figure 3, it can be seen that when control signal P1, P4 is high level, and P2, P3 are low level, power switch pipe V1,
V4 turns on, and V2, V3 are off state, and electric current returns through V1, left buffer inductance LS1, transformator T1 primary coil, V4
To power cathode.Electric current due to flowing through LS1 can not be mutated, and the electric current flowing through V1, V4 is increase of starting from scratch, so
V1, V4 are zero current passings；Meanwhile, power supply VP passes through V1, LS1, D2, LS3 to Absorption Capacitance CS1 charging,
On the CS1 voltage and VP equal till.When P1, P4 are changed into low level, due to the voltage on CS1 and VP voltage
Equal, V1 is zero voltage turn-off, CS2 is no-voltage, and V4 is also zero voltage turn-off.When V1, V4 turn off, LS1
Energy storage pass through D2, absorption inductor LS3 to CS1 charge；Charged to CS2 by T1 primary coil, D4, LS4, keep away
Exempt from the appearance of the upper due to voltage spikes of V3, V4.
As a same reason, when P2, P3 are high level, and P1, P4 are low level, V2, V3 turn on, and V1, V4 are off
State, electric current returns to power cathode through V2, LS2, T1 primary coil, V3.Due to flowing through the electric current of right buffer inductance LS2
Can not be mutated, the electric current flowing through V2, V3 is increase of starting from scratch, so V2, V3 are zero current passings；Meanwhile,
Power supply VP passes through V2, LS2, D4, LS4 and charges to CS2, on the CS2 voltage and VP equal till.As P2, P3
When being changed into low level, because the voltage on CS2 and VP voltage are equal, V2 is zero voltage turn-off, CS1 is no-voltage,
V3 is also zero voltage turn-off.When V2, V3 turn off, the energy storage of inductance is passed through D4, LS4 and is charged to CS2；By at the beginning of T1
Level coil, D2, LS3 charge to CS1, it is to avoid the appearance of the upper due to voltage spikes of V3, V4.
Can be seen that from Fig. 4 soft switch transducer switching loss generation schematic diagram and opened using the bridge converter power of the present invention
The intersection point closing pipe in switch transition period electric current and voltage substantially moves down, and that is, the switching loss of power switch pipe substantially reduces.
Claims (5)
1. it is applied to the passive flexible switch full-bridge type translation circuit of fixed frequency, including hard switching full-bridge type translation circuit, institute
State hard switching full-bridge type translation circuit to include exporting transformator (T1), left arm path and right arm path；Described left brachium pontis
Branch road and right arm path all include power switch pipe (V1, V2), lower power switch pipe (V3, V4)；Described output
Transformator (T1) is connected between the drain electrode of two lower power switch pipes (V3, V4)；It is characterized in that：
Also include buffer cell, absorptive unit, compensating unit；
Described buffer cell include being serially connected in respectively power switch pipe (V1, V2) and lower power switch pipe (V3, V4) it
Between left buffer inductance (LS1) and right buffer inductance (LS2)；
Described absorptive unit includes left absorption branch road and right absorption branch road, and described left absorption branch road and right absorption branch road all include inhaling
Receive diode (D2, D4), absorption inductor (LS3, LS4) and Absorption Capacitance (CS1, CS2)；Described absorption diode
The positive pole of (D2, D4) is connected with the drain electrode of lower power switch pipe (V3, V4), its negative pole and absorption inductor (LS3, LS4)
One end be connected；The other end of described absorption inductor is connected with the one end of Absorption Capacitance (CS1, CS2)；Described Absorption Capacitance
The other end of (CS1, CS2) is connected with the source electrode of lower power switch pipe (V3, V4)；
Described compensating unit includes left compensation diode (D1) and right compensation diode (D3)；Described left compensation diode (D1)
Positive pole be connected with one end of Absorption Capacitance (CS1), its negative pole is connected with the source electrode of upper power switch pipe (V1)；Described
The right positive pole compensating diode (D3) is connected with one end of Absorption Capacitance (CS2), its negative pole and upper power switch pipe (V2)
Source electrode be connected.
2. the passive flexible switch full-bridge type translation circuit being applied to fixed frequency according to claim 1, its feature exists
In：Described absorption diode is high speed fast recovery diode.
3. the passive flexible switch full-bridge type translation circuit being applied to fixed frequency according to claim 1, its feature exists
In：Described Absorption Capacitance is the noninductive absorption capacitor of high frequency.
4. it is applied to the passive flexible switch full-bridge type alternative approach of fixed frequency, the conversion of hard switching full-bridge type is controlled using PWM
The conducting of circuit；It is characterized in that：Comprise the following steps：
1) when the corresponding power switching tube that PWM controls is opened, make the electric current of main brachium pontis pass through a buffer inductance, realize
Zero current turning-on；
2), after this power switch pipe is opened, hard switching full-bridge type translation circuit works；
3) when this power switch pipe is closed, with being connected in parallel on the Absorption Capacitance of lower brachium pontis power switch pipe, realize no-voltage and close；
4), before this power switch pipe is opened to next time after closing, the electric energy of Absorption Capacitance is passed through to compensate diode feed-in power supply
In, realize the lossless reset of Absorption Capacitance.
5. the passive flexible switch full-bridge type alternative approach being applied to fixed frequency according to claim 4, its feature exists
In：Described step 1 is also included the charging current of Absorption Capacitance by a buffer inductance come surge current suppression.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610480476.9A CN106411106A (en) | 2016-06-27 | 2016-06-27 | Passive soft switching full-bridge conversion circuit and method suitable for fixed frequency |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610480476.9A CN106411106A (en) | 2016-06-27 | 2016-06-27 | Passive soft switching full-bridge conversion circuit and method suitable for fixed frequency |
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| CN106411106A true CN106411106A (en) | 2017-02-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201610480476.9A Pending CN106411106A (en) | 2016-06-27 | 2016-06-27 | Passive soft switching full-bridge conversion circuit and method suitable for fixed frequency |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109802585A (en) * | 2019-03-27 | 2019-05-24 | 西安太世德航空电器有限公司 | The passive flexible switch full-bridge circuit and method that upper and lower bridge arm can be prevented straight-through |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0913919A2 (en) * | 1997-10-29 | 1999-05-06 | Kabushiki Kaisha Meidensha | Power converter |
| CN101478230A (en) * | 2009-01-21 | 2009-07-08 | 东北大学 | Passive soft on-off circuit used for inversion bridge |
| CN104242621A (en) * | 2013-06-11 | 2014-12-24 | Abb研究有限公司 | Lc snubber circuit |
| CN205753949U (en) * | 2016-06-27 | 2016-11-30 | 西安太世德航空电器有限公司 | It is applicable to the passive flexible switch full-bridge type translation circuit of fixed frequency |
-
2016
- 2016-06-27 CN CN201610480476.9A patent/CN106411106A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0913919A2 (en) * | 1997-10-29 | 1999-05-06 | Kabushiki Kaisha Meidensha | Power converter |
| CN101478230A (en) * | 2009-01-21 | 2009-07-08 | 东北大学 | Passive soft on-off circuit used for inversion bridge |
| CN104242621A (en) * | 2013-06-11 | 2014-12-24 | Abb研究有限公司 | Lc snubber circuit |
| CN205753949U (en) * | 2016-06-27 | 2016-11-30 | 西安太世德航空电器有限公司 | It is applicable to the passive flexible switch full-bridge type translation circuit of fixed frequency |
Non-Patent Citations (1)
| Title |
|---|
| 王京梅等: "零电压-零电流PWM软开关技术研究", 《电子器件》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109802585A (en) * | 2019-03-27 | 2019-05-24 | 西安太世德航空电器有限公司 | The passive flexible switch full-bridge circuit and method that upper and lower bridge arm can be prevented straight-through |
| CN109802585B (en) * | 2019-03-27 | 2023-12-19 | 西安太世德航空电器有限公司 | Passive soft switch full-bridge conversion circuit and method capable of preventing upper bridge arm and lower bridge arm from being directly connected |
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Application publication date: 20170215 |