CN104184322A - Converter of symmetrical structure - Google Patents
Converter of symmetrical structure Download PDFInfo
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- CN104184322A CN104184322A CN201410469892.XA CN201410469892A CN104184322A CN 104184322 A CN104184322 A CN 104184322A CN 201410469892 A CN201410469892 A CN 201410469892A CN 104184322 A CN104184322 A CN 104184322A
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- 238000004146 energy storage Methods 0.000 claims abstract description 52
- 239000000446 fuel Substances 0.000 claims description 10
- 239000003990 capacitor Substances 0.000 abstract description 8
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- 230000002035 prolonged effect Effects 0.000 abstract 1
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- 230000001172 regenerating effect Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
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- 230000005611 electricity Effects 0.000 description 2
- 101100112673 Rattus norvegicus Ccnd2 gene Proteins 0.000 description 1
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- 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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
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Abstract
The invention discloses a converter device of a symmetrical structure. The converter device of the symmetrical structure comprises two input power sources V1 and V2, an input capacitor C1, an output capacitor C2, two energy storage inductors L1 and L2 and three switching tubes, wherein an adjusting voltage Uc is generated across the two ends of the input capacitor C1, and an output voltage Vo is generated across the two ends of the output capacitor C2. According to a direct-current converter, due to switch-on and switch-off of the first switching tube, the second switching tube and the third switching tube, the adjusting voltage Uc generated on the input capacitor C1, and the combined action between the adjusting voltage Uc and an input current I1 generated by the input power source V1 as well as between the adjusting voltage Uc and an input current I2 generated by the input power source V2, an output current IC is generated to the output capacitor C2, and the magnitude of the output current IC can be increased or decreased through combination between different switching tubes. The input current and the output voltage of the direct-current converter are small in ripple, the service life of the input power sources can be easily prolonged, the device is simple in structure, small in number of required switching devices, low in loss and high in efficiency, performance of the converter can be effectively improved, cost can be reduced, and the output current is controllable.
Description
Technical field
The present invention relates to a kind of converter, especially a kind of DC converter of symmetrical structure.
Background technology
In recent years, the shortage of the energy and the pollution of environment have become the focus in the world, and the development of regenerative resource and application are subject to the extensive concern of countries in the world.In renewable energy system, the electric energy that many regenerative resources are sent is all the direct current that voltage is lower, and need to grid transmission the direct current that voltage is higher, therefore need DC-to-DC converter that low voltage and direct current is converted to and is applicable to grid-connected high-voltage direct-current electricity.In clean energy resource electric automobile field, often need the single direct current of low pressure that battery is provided to be converted to the high voltage direct current of different magnitudes of voltage, this just has very high requirement aspect the stability of the efficiency in DC-DC conversion and output dc voltage.So low output voltage ripple, high-gain, high efficiency converter regenerative resource generate electricity by way of merging two or more grid systems and clean energy resource electric automobile application in have very important effect.For the voltage of photovoltaic or fuel cell array being risen to the required DC bus-bar voltage of combining inverter, conventionally photovoltaic or fuel cell array are connected, then adopt BOOST or two-phase crisscross parallel BOOST circuit to boost, the no-load voltage ratio of boosting of these two kinds of Structural Transformation devices equates, in the time that input voltage is lower, in order to reach higher output voltage, its switch conduction duty ratio will be close to 1, can reduce so on the one hand the efficiency of converter, Simultaneous Switching frequency is also difficult for further improving.In order to reach the higher no-load voltage ratio of boosting, also there is document to propose using two direct cascades of BOOST converter as front stage converter, increase like this complexity of the sum of series control of system, be unfavorable for the raising of system effectiveness and the improvement of performance, therefore the DC-DC converter of studying novel high-performance and having a no-load voltage ratio of boosting more greatly meets the needs of rear class combining inverter, has important theoretical significance and application value.
A kind of combined DC/DC converter as disclosed in open source literature (CN102223068B), comprise two direct-current input power supplyings (Vin1, Vin2) (1), can be the booster converter module of photovoltaic cell or fuel cell, two full symmetrics 2. and 3.) composition.2. booster converter module is made up of two boost inductances (L1, L3), two power switch pipes (Q1, Q3), four one-way commutation diodes (D1～D4), two intermediate energy storage electric capacity (C1, C3), an output filter capacitor (Co1); 3. booster converter module is made up of two boost inductances (L2, L4), two power switch pipes (Q2, Q4), four one-way commutation diodes (D5～D8), two intermediate energy storage electric capacity (C2, C4), an output filter capacitor (Co2).Regard Q1, Q2 as one group of synchro switch, drive with same driving signal 1, Q3, Q4 are one group of synchro switch, drive signal 2 to drive with one; Adopt the two groups of switching tubes of method control that drive signal complementation.But its structure, control complexity, required switching device is more, and output current is unadjustable, causes converter cost higher, is unfavorable for applying.
Summary of the invention
The object of the invention is to the shortcoming for transformer configuration in prior art, propose the DC converter of the less symmetrical structure of a kind of switching device simple in structure, required, and loss is less, converter conversion efficiency is high.
The DC converter of symmetrical structure of the present invention comprises: 2 input power V1, V2, 1 input capacitance C1 also produces regulation voltage Uc at its two ends, 1 output capacitance C2 also produces output voltage V o at its two ends, 2 energy storage inductor L1, L2 and 3 switching tubes, it adopts symmetrical structure setting, concrete topological structure is: the negative pole of input power V1 connects the lower end of input capacitance C1, the positive pole of input power V1 connects one end of the first switching tube S1, the positive pole of input power V2 connects the upper end of input capacitance C1, the upper end of input capacitance C1 connects one end of the first energy storage inductor L1, the lower end of input capacitance C1 connects one end of the second energy storage inductor L2, the other end of the first energy storage inductor L1 connects the other end of the first switching tube S1, and this tie point connects one end of second switch pipe S2, the other end of the second energy storage inductor L2 connects the other end of second switch pipe S2, and this tie point connects one end of the 3rd switching tube S3, the other end of the 3rd switching tube S3 connects the negative pole of input power V2, output capacitance C2 anode connects the positive pole of input power V1, the negative terminal of output capacitance C2 connects the negative pole of input power V2, the first～three switching tube all has anti-paralleled diode, this DC converter turns on and off by the first～three switching tube, the regulation voltage Uc producing on input capacitance C1, and the input current I that described regulation voltage Uc and input power V1 produce
1input current I with input voltage V2 generation
2acting in conjunction produces output current I
cto output capacitance C2, and different switch combinations can make output current I
cincrease or reduce.
In the time that regulation voltage Uc is upper just lower bearing, second switch pipe S2 conducting, the first switching tube S1, the 3rd switching tube S3 turn-off, and input capacitance C1, the first energy storage inductor L1, the second energy storage inductor L2 form circulation, and on the first energy storage inductor L1, produce the first energy storage electric current I
l1, on the second energy storage inductor L2, produce the second energy storage electric current I
l2.In the situation that second switch pipe S2 turn-offs, the first switching tube S1 and the 3rd switching tube S3 conducting, be stored in the energy storage electric current I in the first energy storage inductor and the second energy storage inductor
l1, I
l2flow to output capacitance C2 through the first switching tube S1 and the 3rd switching tube S3, meanwhile, input current I
1with input current I
2also directly flow to output capacitance C2 from input power V1, V2, reach the object of output voltage, now flow to the magnitude of current I of output capacitance
cwill be due to I
l1and I
l2shunting increase accordingly.
When regulation voltage Uc is upper negative lower timing, the first switching tube S1, the 3rd switching tube S3 conducting, second switch pipe S2 turn-offs, compared with just lower negative on regulation voltage Uc time, under the effect of input power V1, V2 and input capacitance C1, the first contrary energy storage electric current I will be produced on the first energy storage inductor L1
l1with on the second energy storage inductor L2, produce the second contrary energy storage electric current I
l2, and be stored in energy storage inductor L1, L2, next, the first switching tube S1, the 3rd switching tube S3 turn-off, when second switch pipe S2 conducting, in the first energy storage electric current I
l1with the energy storage electric current I of storing in the second energy storage inductor L2
l1and I
l2through second switch pipe, S2 flows to input capacitance C1, meanwhile, and input current I
1with input current I
2directly flow to output capacitance C2 from input power V1, V2, reach the object of output voltage, now flow to the magnitude of current I of output capacitance
cwill be due to I
l1and I
l2shunting reduce accordingly.
The first～three switching tube can be the high-power switch device such as IGBT or MOSFET.It is that storage battery, input power V2 are that photovoltaic cell or described input power V1, V2 are the combination of any two kinds in three kinds of storage battery, fuel cell or photovoltaic cells that input power V1, V2 are all a kind of or described input power V1 in the novel energy-storing power supplys such as storage battery, fuel cell or photovoltaic cell.
The input current of DC converter of the present invention and the ripple of output voltage are less, are conducive to extend the useful life of input power, and simple in structure, required switching device is less, loss is little, efficiency is high, can effectively improve the performance of converter and reduce costs, and output current is controlled.
Brief description of the drawings
Fig. 1: the topology diagram of the converter of existing symmetrical structure;
Fig. 2: the topology diagram of the DC converter of symmetrical structure of the present invention.
Embodiment
As shown in Figure 2, the application's DC converter comprises 2 input power V1, V2, 1 input capacitance C1 also produces regulation voltage Uc at its two ends, 1 output capacitance C2 also produces output voltage V o at its two ends, 2 energy storage inductor L1, L2 and 3 switching tubes, it adopts symmetrical structure setting, concrete topological structure is: the negative pole of input power V1 connects the lower end of input capacitance C1, the positive pole of input power V1 connects one end of the first switching tube S1, the positive pole of input power V2 connects the upper end of input capacitance C1, the upper end of input capacitance C1 connects one end of the first energy storage inductor L1, the lower end of input capacitance C1 connects one end of the second energy storage inductor L2, the other end of the first energy storage inductor L1 connects the other end of the first switching tube S1, and this tie point connects one end of second switch pipe S2, the other end of the second energy storage inductor L2 connects the other end of second switch pipe S2, and this tie point connects one end of the 3rd switching tube S3, the other end of the 3rd switching tube S3 connects the negative pole of input power V2, output capacitance C2 anode connects the positive pole of input power V1, the negative terminal of output capacitance C2 connects the negative pole of input power V2, the first～three switching tube all has anti-paralleled diode, the first～three switching tube can be the high-power switch device such as IGBT or MOSFET.Input power V1, V2 are the novel energy-storing power supplys such as storage battery, fuel cell or photovoltaic cell.
The application's DC converter turns on and off by the first～three switching tube, the regulation voltage Uc producing on input capacitance C1, and the input current I that coordinates input power V1 to produce
1input current I with input voltage V2 generation
2output to output capacitance C2.
In the time that regulation voltage Uc is upper just lower bearing, second switch pipe S2 conducting, the first switching tube S1, the 3rd switching tube S3 turn-off, and input capacitance C1, the first energy storage inductor L1, the second energy storage inductor L2 form circulation, and on the first energy storage inductor L1, produce the first energy storage electric current I
l1, on the second energy storage inductor L2, produce the second energy storage electric current I
l2.In the situation that second switch pipe S2 turn-offs, the first switching tube S1 and the 3rd switching tube S3 conducting, be stored in the energy storage electric current I in the first energy storage inductor and the second energy storage inductor
l1, I
l2flow to output capacitance C2 through second switch pipe S2 and the 3rd switching tube S3, meanwhile, input current I
1with input current I
2also directly flow to output capacitance C2 from input power V1, V2, reach the object of output voltage, now flow to the magnitude of current I of output capacitance
cwill be due to I
l1and I
l2shunting increase accordingly.
When regulation voltage Uc is upper negative lower timing, the first switching tube S1, the 3rd switching tube S3 conducting, second switch pipe S2 turn-offs, compared with just lower negative on regulation voltage Uc time, under the effect of input power V1, V2 and input capacitance C1, the first contrary energy storage electric current I will be produced on the first energy storage inductor L1
l1with on the second energy storage inductor L2, produce the second contrary energy storage electric current I
l2, and be stored in energy storage inductor L1, L2, next, the first switching tube S1, the 3rd switching tube S3 turn-off, when second switch pipe S2 conducting, in the first energy storage electric current I
l1with the energy storage electric current I of storing in the second energy storage inductor L2
l1and I
l2through second switch pipe, S2 flows to input capacitance C1, meanwhile, and input current I
1with input current I
2directly flow to output capacitance C2 from input power V1, V2, reach the object of output voltage, now flow to the magnitude of current I of output capacitance
cwill be due to I
l1and I
l2shunting reduce accordingly.
The first～three switching tube can be the high-power switch device such as IGBT or MOSFET.It is that storage battery, input power V2 are that photovoltaic cell or described input power V1, V2 are the combination of any two kinds in three kinds of storage battery, fuel cell or photovoltaic cells that input power V1, V2 are all a kind of or described input power V1 in the novel energy-storing power supplys such as storage battery, fuel cell or photovoltaic cell.
Claims (5)
1. the DC converter of a symmetrical structure, comprise input power V1, V2, input capacitance C1 also produces regulation voltage Uc at its two ends, output capacitance C2 also produces output voltage V o at its two ends, energy storage inductor L1, L2 and first～three switching tube S1, S2, S3, this DC converter adopts symmetrical structure setting, concrete topological structure is: the negative pole of input power V1 connects the lower end of input capacitance C1, the positive pole of input power V1 connects one end of the first switching tube S1, the positive pole of input power V2 connects the upper end of input capacitance C1, the upper end of input capacitance C1 connects one end of the first energy storage inductor L1, the lower end of input capacitance C1 connects one end of the second energy storage inductor L2, the other end of the first energy storage inductor L1 connects the other end of the first switching tube S1, and this tie point connects one end of second switch pipe S2, the other end of the second energy storage inductor L2 connects the other end of second switch pipe S2, and this tie point connects one end of the 3rd switching tube S3, the other end of the 3rd switching tube S3 connects the negative pole of input power V2, output capacitance C2 anode connects the positive pole of input power V1, the negative terminal of output capacitance C2 connects the negative pole of input power V2, the first～three switching tube all has anti-paralleled diode, this DC converter turns on and off by the first～three switching tube, the regulation voltage Uc producing on input capacitance C1, and the input current I of described regulation voltage Uc and input power V1 generation
1input current I with input voltage V2 generation
2acting in conjunction produces output current I
cto output capacitance C2, and different switch combinations can make output current I
cincrease or reduce.
2. the DC converter of symmetrical structure according to claim 1, described the first～three switching tube is IGBT or MOSFET.
3. the DC converter of symmetrical structure according to claim 1, described input power V1, V2 are all the one in the novel energy-storing power supplys such as storage battery, fuel cell or photovoltaic cell.
4. the DC converter of symmetrical structure according to claim 1, described input power V1 is that storage battery, input power V2 are photovoltaic cell.
5. the DC converter of symmetrical structure according to claim 1, described input power V1, V2 are respectively the combination of any two kinds in three kinds of storage battery, fuel cell or photovoltaic cells.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410469892.XA CN104184322B (en) | 2014-09-15 | 2014-09-15 | A kind of converter of symmetrical structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410469892.XA CN104184322B (en) | 2014-09-15 | 2014-09-15 | A kind of converter of symmetrical structure |
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|---|---|
| CN104184322A true CN104184322A (en) | 2014-12-03 |
| CN104184322B CN104184322B (en) | 2016-04-20 |
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|---|---|---|---|
| CN201410469892.XA Active CN104184322B (en) | 2014-09-15 | 2014-09-15 | A kind of converter of symmetrical structure |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101247085A (en) * | 2008-03-14 | 2008-08-20 | 浙江大学 | Passive-clamp alternation and parallel connection boosting converter |
| US20100072819A1 (en) * | 2008-09-22 | 2010-03-25 | Ablerex Electronics Co., Ltd | Bi-directional DC to DC power converter having a neutral terminal |
-
2014
- 2014-09-15 CN CN201410469892.XA patent/CN104184322B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101247085A (en) * | 2008-03-14 | 2008-08-20 | 浙江大学 | Passive-clamp alternation and parallel connection boosting converter |
| US20100072819A1 (en) * | 2008-09-22 | 2010-03-25 | Ablerex Electronics Co., Ltd | Bi-directional DC to DC power converter having a neutral terminal |
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| Publication number | Publication date |
|---|---|
| CN104184322B (en) | 2016-04-20 |
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Effective date of registration: 20191031 Address after: 314500, No. 3736 East Ring Road, Jiaxing, Zhejiang, Tongxiang Patentee after: ZHEJIANG WUXIAN NEW ENERGY Co.,Ltd. Address before: 224051 Yancheng City hope road, Jiangsu, No. 9 Patentee before: YANCHENG INSTITUTE OF TECHNOLOGY |
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Effective date of registration: 20200403 Address after: 314500 No. 4000 Triumph Road, Wutong Street, Tongxiang City, Jiaxing City, Zhejiang Province Patentee after: ZHEJIANG CHUANGJIA ELECTROMECHANICAL EQUIPMENT Co.,Ltd. Address before: 314500, No. 3736 East Ring Road, Jiaxing, Zhejiang, Tongxiang Patentee before: ZHEJIANG WUXIAN NEW ENERGY Co.,Ltd. |
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Denomination of invention: A symmetrical converter Effective date of registration: 20210929 Granted publication date: 20160420 Pledgee: Zhejiang Tongxiang Rural Commercial Bank Co.,Ltd. Yuqiao sub branch Pledgor: ZHEJIANG CHUANGJIA ELECTROMECHANICAL EQUIPMENT Co.,Ltd. Registration number: Y2021330001828 |
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Date of cancellation: 20221012 Granted publication date: 20160420 Pledgee: Zhejiang Tongxiang Rural Commercial Bank Co.,Ltd. Yuqiao sub branch Pledgor: ZHEJIANG CHUANGJIA ELECTROMECHANICAL EQUIPMENT CO.,LTD. Registration number: Y2021330001828 |
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Denomination of invention: A symmetrical converter Effective date of registration: 20221207 Granted publication date: 20160420 Pledgee: Yuebei sub branch of Zhejiang Tongxiang Rural Commercial Bank Co.,Ltd. Pledgor: ZHEJIANG CHUANGJIA ELECTROMECHANICAL EQUIPMENT CO.,LTD. Registration number: Y2022330003515 |
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Denomination of invention: A symmetrical structure converter Granted publication date: 20160420 Pledgee: Yuebei sub branch of Zhejiang Tongxiang Rural Commercial Bank Co.,Ltd. Pledgor: ZHEJIANG CHUANGJIA ELECTROMECHANICAL EQUIPMENT CO.,LTD. Registration number: Y2024980009839 |
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