CN107834888A - A kind of Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp - Google Patents
A kind of Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp Download PDFInfo
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- CN107834888A CN107834888A CN201710964980.0A CN201710964980A CN107834888A CN 107834888 A CN107834888 A CN 107834888A CN 201710964980 A CN201710964980 A CN 201710964980A CN 107834888 A CN107834888 A CN 107834888A
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- 238000005516 engineering process Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 2
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- 238000012360 testing method Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
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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
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
- H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
- H02M7/53871—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current
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- H02J3/383—
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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
- H02M1/12—Arrangements for reducing harmonics from ac input or output
-
- 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
- H02M1/12—Arrangements for reducing harmonics from ac input or output
- H02M1/123—Suppression of common mode voltage or current
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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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- Inverter Devices (AREA)
Abstract
The invention discloses a kind of Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp, including energy storage partial pressure unit, power inverting unit, hybrid clamp unit and filter unit.During inverter work of the present invention, the anti-and power switch coordination of diode by five bands, it is aided with six diodes, during so that inverter exporting zero level, AC carries out afterflow, and by the half of its common-mode voltage clamper to DC input voitage, so that it is guaranteed that common-mode voltage is constant in whole cycle, and then being completely eliminated for common mode current is realized, and required busbar voltage is only the half of semi-bridge type circuit.The present invention uses unipolar pulse width modulated simultaneously, and output current ripple is small, reduces the volume and quality of wave filter, while reduces the loss on magnetic element；Switch motion number is few in switch periods, reduces switching loss, therefore the delivery efficiency of inverter of the present invention is high, can obtain up to 98% inversion efficiency.
Description
Technical field
The invention belongs to electric and electronic technical field, and in particular to a kind of single-phase light of Transformer-free of voltage hybrid clamp
Lie prostrate inverter.
Background technology
Nowadays, lack of energy and problem of environmental pollution getting worse, the utilization of various new energy are more and more by weight
Depending on.Solar energy as presently most clean, one of regenerative resource for most having the prospect of large-scale developing and utilizing, its photovoltaic utilize by
The common concern of countries in the world is arrived.And solar energy power generating is the Main Trends of The Development of solar energy photovoltaic utilization, in future
It will obtain more and more rapidly developing.
Inverter is as most end one-level in photovoltaic generating system or unique one-level energy converter, its efficiency and security
It can will directly affect performance and the investment of whole system.Transformer configuration situation in inverter, can will be existing inverse
Become device and be divided into band Industrial Frequency Transformer type inverter, band high frequency transformer type inverter and inverter without transformer.Band power frequency becomes
The inverter of depressor or high frequency transformer can realize the function of boosting and isolation, but be deposited with Industrial Frequency Transformer type inverter
Become the problem of big, price is high and installation is inconvenient in volume and weight；Although band high frequency transformer type inverter volume and weight is big
It is big to reduce, but the structure of multi-stag causes system architecture complicated, and whole efficiency reduces.And inverter without transformer is due to it
Unite simple in construction, efficiency high, small volume, low cost and other advantages, obtained increasing attention.
In Transformer-free photovoltaic parallel in system, due to losing the electrical isolation of transformer, photovoltaic battery array with
Common mode loop as shown in Figure 1 will be formed between parasitic capacitance, photovoltaic combining inverter and the earth between the earth.Data shows
Show, parasitic capacitance be present between the slab construction and the earth of crystal silicon photovoltaic battery is about 50-150nF/kWp, and its capacitance is much larger than
The parasitic capacitance over the ground of power device.Therefore, if dither in the common-mode voltage of system be present, then in common mode loop just
Larger common mode leakage current can be produced.The common mode leakage current can not only cause serious EMI problems, while can also reduce grid-connected electricity
Family status matter, and bring hidden danger to the personal safety of photovoltaic cell attendant.Therefore, in Transformer-free combining inverter
In, it is necessary to solve the problems, such as high frequency common mode current.
In existing published technology, one end of power network is directly clamped to by half-bridge inversion circuit and neutral-point-clamped circuit
The midpoint of DC bus-bar voltage so that the parasitic capacitance both end voltage of photovoltaic cell is constant, so as to inhibit the production of common mode current
It is raw.But the DC bus-bar voltage required in above two scheme is twice of busbar voltage needed for common full-bridge, therefore,
Under the relatively low occasion of DC input voitage, both schemes must lift busbar voltage by booster circuit boosting.Prime liter
The use of volt circuit not only increases the cost of system, while also reduces the overall transformation efficiency of inverter.
Publication No. EP2086102A2 European patent discloses one kind efficiently without common mode current type topological structure
(HERIC), program required input voltage is the half of semi-bridge type inverter circuit, therefore in many instances, without extra
Booster circuit boosts to bus.The program adds two derailing switches on the basis of common full-bridge topology, in AC
Part.In the direct current lateral AC transmission energy stage, the work of the circuit is identical with full-bridge unipolarity circuit, the common mode electricity of system
Press the half for input voltage；In Inductor freewheeling period, the AC switching tube of HERIC structures turns on, and ensure that and is
While system output zero level, the decoupling of DC side and AC is realized, now the common-mode voltage of system is in the ideal case
It is maintained at the half of input voltage.Therefore, high frequency componentses are not present in the common-mode voltage of the circuit, and then inhibit the common mode of system
Leakage current.But under actual condition, during due to DC side with exchanging lateral circuit decoupling, the voltage of AC relative to DC side at
In suspended state, and and the non-constant half in DC input voitage, consider circuit in parasitic parameter：Tied as switching tube exports
High-frequency resonant occurs for electric capacity, lead-in inductance equal distribution parameter etc., inductance, electric capacity in above-mentioned parameter and common mode loop, causes and is
High frequency common mode current in the common mode loop of system.Therefore, the technology can not realize being completely eliminated for high frequency common mode current.
Publication No. EP1626494A2's has the H5 of drain current suppressing ability is topological to tie European patent discloses another
Structure, the structure add power switch in the DC side of full-bridge circuit, so that it is guaranteed that the DC side of grid-connected inductance freewheeling period with
The decoupling of AC.The circuit is similar with HERIC circuits, and common mode leakage current can not be completely eliminated.In addition, its circuit structure is not right
Claim, 5 switching transistor operating times are unequal, cause MOS switch dissipation unbalanced, and device heat dissipation design requires higher；
Energy transfer stages, there are three power devices (being 2 in HERIC topologys) in the conduction state, reduce the entirety of inverter
Efficiency.
The content of the invention
For the above-mentioned technical problem present in prior art, the invention provides a kind of voltage hybrid clamp without transformation
Type single-phase photovoltaic inverter, it can effectively eliminate high frequency common mode current and high conversion efficiency.
A kind of Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp, including：
Energy storage partial pressure unit, for carrying out energy storage and partial pressure to the photovoltaic DC voltage of input；
Power inverting unit, for being three level DC voltage by described photovoltaic DC voltage conversion；
Hybrid clamp unit, for when power inverting unit exports zero level, afterflow to be carried out to inverter ac side, and
Afterflow mid-point voltage is clamped to the half of photovoltaic DC voltage；
Filter unit, for carrying out LPF to described three level DC voltage, so as to export sinusoidal voltage.
Described energy storage partial pressure unit includes two input capacitance Cdc1~Cdc2；Wherein, input capacitance Cdc1Positive pole and light
The positive pole of volt DC source is connected, input capacitance Cdc1Negative pole and input capacitance Cdc2Positive pole be connected, input capacitance Cdc2Negative pole
It is connected with the negative pole in photovoltaic DC source.
Described input capacitance Cdc1And Cdc2Formed by an electrochemical capacitor composition or by multiple electrochemical capacitor connection in series-parallel.
Described power inverting unit uses single-phase full bridge inverter structure, and it includes, and four bands are anti-and the power of diode is opened
Close pipe S1~S4；Wherein, one end of power switch tube S 1 is connected with one end of power switch tube S 3 and connects photovoltaic DC source just
Pole, one end of power switch tube S 2 are connected with one end of power switch tube S 4 and connect the negative pole in photovoltaic DC source, power switch pipe
The S1 other end is connected the first voltage output end as power inverting unit with the other end of power switch tube S 2, power switch
The pipe S3 other end is connected the second voltage output end as power inverting unit with the other end of power switch tube S 4；Four work(
Rate switching tube S1~S4 receives the switch controlling signal of external equipment offer.
Described hybrid clamp unit includes a power switch tube S 5 and six diode D1~D6；Wherein, power is opened
The one end for closing pipe S5 is connected with diode D2, D4 and D6 negative electrode, the other end and diode D1, D3 and D5 of power switch pipe
Anode is connected, and diode D1 negative electrode is connected with diode D2 anode and connects the first voltage output end of power inverting unit,
Diode D3 negative electrode is connected with diode D4 anode and connects the second voltage output end of power inverting unit, diode D5's
Negative electrode is connected with diode D6 anode and energy storage partial pressure unit to extract the photovoltaic DC voltage of half；Power switch pipe
S5 receives the switch controlling signal that external equipment provides.
Described power switch pipe uses IGBT (insulated gate bipolar transistor).
Described filter unit uses symmetric inductor wave filter or symmetric form LCL (inductor-capacitor-inductance) wave filter.
Described symmetric inductor wave filter includes two filter inductance L1~L2；Wherein, filter inductance L1One end and work(
The first voltage output end of rate inversion unit is connected, filter inductance L2One end and power inverting unit second voltage output end
It is connected, filter inductance L1And L2The described sinusoidal voltage of other end output.
Described symmetric form LCL filter includes two filter inductance L1~L2With a filter capacitor C；Wherein, filtered electrical
Feel L1One end be connected with the first voltage output end of power inverting unit, filter inductance L2One end and power inverting unit
Second voltage output end is connected, filter inductance L1And L2The other end be connected respectively with filter capacitor C both ends and export described
Sinusoidal voltage.
The modulation system of single-phase photovoltaic inverter of the present invention uses unipolar pulse width modulated, in power frequency positive half period,
The high frequency mo synchronous with S4 of power switch tube S 1, power switch tube S 2, S3 are remained open, power switch tube S 5 and S1 complementation high frequencies
Action.In power frequency negative half-cycle, the high frequency mo synchronous with S3 of power switch tube S 2, power switch tube S 1, S4 are remained open, power
Switching tube S5 and S2 complementation high frequency mos.
During single-phase photovoltaic inverter work of the present invention, and the power switch coordination of diode anti-by five bands, it is aided with
Six diodes so that during inverter output zero level, AC carries out afterflow, and by hybrid clamp by its common-mode voltage
Clamper so that it is guaranteed that common-mode voltage is constant in whole cycle, and then realizes common mode current to the half of DC input voitage
Be completely eliminated, and required busbar voltage is only the half of semi-bridge type circuit.The present invention is wide using unipolar pulse simultaneously
Degree modulation, output current ripple is small, reduces the volume and quality of wave filter, while reduces the loss on magnetic element；Open
Switch motion number is few in the cycle of pass, reduces switching loss, therefore the delivery efficiency of inverter of the present invention is high, can obtain height
Up to 98% inversion efficiency.
Brief description of the drawings
Fig. 1 is the common mode circuit diagram in Transformer-free photovoltaic system；
Fig. 2 is the topological structure schematic diagram of single-phase photovoltaic inverter of the present invention；
Fig. 3 is the waveform diagram that the present invention uses each switch controlling signal of unipolar pulse width modulation mode；
Fig. 4 (a)~(d) is respectively the principle schematic of 4 kinds of mode of operations of single-phase photovoltaic inverter of the present invention；
Fig. 5 is that single-phase photovoltaic inverter of the present invention and the common mode current of HERIC inverters contrast oscillogram.
Embodiment
In order to more specifically describe the present invention, below in conjunction with the accompanying drawings and embodiment is to technical scheme
It is described in detail.
As shown in Fig. 2 a kind of Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp, including：Energy storage partial pressure list
Member, power inverting unit, hybrid clamp unit and filter unit.Wherein：
Energy storage partial pressure unit is used for energy storage and the photovoltaic DC electricity to input carries out partial pressure, to extract photovoltaic DC output
Mid-point voltage；In present embodiment, it includes the first input capacitance Cdc1, the second input capacitance Cdc2.Wherein, the first input capacitance
Cdc1Positive pole be connected with the positive pole at input direct-current end, the second input capacitance Cdc2Negative pole be connected with the negative pole at input direct-current end,
First input capacitance Cdc1Negative pole and the second input capacitance Cdc2Positive pole be connected to form the voltage midpoint of energy storage partial pressure unit.
Power inverting unit is used to photovoltaic DC electricity being converted to three level DC voltage；In present embodiment, it includes
First power switch tube S1, the second power switch tube S2, the 3rd power switch tube S3, the 4th power switch tube S4.Wherein, first
Power switch tube S1Drain electrode, the 3rd power switch tube S3Drain electrode be connected with the positive pole at input direct-current end；Second power switch pipe
S2Source electrode, the 4th power switch tube S4Source electrode be connected with the negative pole at input direct-current end；First power switch tube S1Source electrode with
Second power switch tube S2Drain electrode be connected to form the first output voltage terminal of power inverting unit；3rd power switch tube S3's
Source electrode and the 4th power switch tube S4Drain electrode be connected to form the second output voltage terminal of power inverting unit.Four power switch
Pipe S1~S4Control pole receive external equipment offer switch controlling signal.
Hybrid clamp unit is used to, when power inverting unit exports zero level, afterflow is carried out to AC, and by afterflow
Mid-point voltage is clamped to the mid-point voltage of photovoltaic DC output；In present embodiment, it includes a power switch tube S 5 and six
The one end of individual diode D1~D6, diode D2, D4 and D6 negative electrode with power switch tube S 5 is connected, diode D1, D3 and
D5 anode is connected with the other end of power switch pipe, and diode D1 negative electrode is connected with diode D2 anode and connects power
The first voltage output end of inversion unit, diode D3 negative electrode are connected with diode D4 anode and connect power inverting unit
Second voltage output end, diode D5 negative electrode are connected with diode D6 anode and connect the mid-point voltage end of energy storage partial pressure unit
Mouthful；Power switch tube S 5 receives the switch controlling signal that external equipment provides.
Filter unit is used to carry out LPF to three level DC voltage, so as to export sinusoidal voltage；This implementation
In mode, it uses exchange output filter F.Wherein, the first output of wave filter F first input end and power inverting unit
Voltage end is connected, and wave filter F the second input is connected with the second output voltage terminal of power inverting unit, and the of wave filter F
First, the second output end is connected with AC network both ends.
First power switch S in present embodiment1By first switch transistor T1With the first anti-and diode DT1It is in parallel and
Into the second power switch S2By second switch transistor T2With the second anti-and diode DT2It is formed in parallel, the 3rd power switch S3By
3rd switching transistor T3With the 3rd anti-and diode DT3It is formed in parallel, the 4th power switch S4By the 4th switching transistor T4With
4th anti-and diode DT4It is formed in parallel, the 5th power switch S5By the 5th switching transistor T5With the 5th anti-and diode DT5And
Connection forms；Switching transistor and the parallel way of anti-simultaneously diode are：The drain electrode of switching transistor or colelctor electrode and anti-and two poles
The negative electrode of pipe, which is connected, forms the drain electrode of power switch, and the source electrode or emitter stage of switching transistor are connected with anti-and diode anode
Form the source class of power switch.
Input capacitance in present embodiment uses electrochemical capacitor, and power switch pipe is managed using IGBT, and wave filter uses
Symmetrical inductance L1And L2, modulation system is unipolar pulse width modulated.
Fig. 3 is the waveform diagram that the present invention uses unipolar pulse width modulation mode.In power frequency positive half period, first
Switching transistor T1With the 4th switching transistor T4Synchronous high frequency mo, second switch transistor T2, the 3rd switching transistor T3、
5th switching transistor T5With first switch transistor T1Complementary high frequency mo.In power frequency negative half-cycle, second switch transistor T2
With the 3rd switching transistor T3Synchronous high frequency mo, first switch transistor T1, the 4th switching transistor T4Remain open, the 5th
Switching transistor T5With second switch transistor T2Complementary high frequency mo.
Present embodiment inverter is primarily present 4 kinds of Working moulds as shown in Fig. 4 (a)~(d) in whole work process
State.In operation mode 1, electric current flows successively through first switch transistor T1, filter inductance L1, power network, filter inductance L2, the 4th
Switching transistor T4, inverter output positive voltage.In operation mode 2, electric current flows successively through filter inductance L1, power network, filtered electrical
Feel L2, diode D4, the 5th switching transistor T5, diode D1, inverter output no-voltage.In operation mode 3, electric current according to
It is secondary to flow through the 3rd switching transistor T3, filter inductance L2, power network, filter inductance L1, second switch transistor T2, inverter output
Negative voltage.In operation mode 4, electric current flows successively through filter inductance L2, power network, filter inductance L1, diode D2, the 5th switch
Transistor T5, diode D3, inverter output no-voltage.In operation mode 1,3, VCM=(VAN+VBN)/2=VDC/2.In work
Make in mode 2,4, first switch transistor T1With the first anti-and diode D1, second switch transistor T2With the second anti-and two poles
Pipe D2, the 3rd switching transistor T3With the 3rd anti-and diode D3, the 4th switching transistor T4With the 4th anti-and diode D4Close
It is disconnected.VAN、VBNBy diode D5 or D6 clamper to electric capacity mid-point voltage, so (VAN+VBN)/2=VDC/2.Therefore in whole process
Common-mode voltage is steady state value, so as to ensure effective suppression of common mode current.
Single-phase inverter under present embodiment for 400V, 2kW power platform test in an input
Card.The leakage current Experimental comparison waveform of present embodiment inverter and HERIC inverters is as shown in figure 5, experimental data illustrates this
The drain current suppressing effect of the voltage hybrid clamp formula Transformer-free single-phase inverter of invention is better than HERIC inverters, simultaneously
The conventional efficient of the single-phase inverter of the present invention is up to 98%.
It is above-mentioned test result indicates that, inverter of the present invention has reliable common mode current rejection ability and high energy
Conversion efficiency, it is highly suitable in the single-phase photovoltaic grid-connected inversion system of Transformer-free.
Finally it should be noted that only illustrating technical scheme rather than its limitations with reference to above-described embodiment.Institute
The those of ordinary skill in category field is it is to be understood that those skilled in the art can repair to the embodiment of the present invention
Change or equivalent substitution, but these modifications or change are among pending claims are applied for.
Claims (9)
- A kind of 1. Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp, it is characterised in that including：Energy storage partial pressure unit, for carrying out energy storage and partial pressure to the photovoltaic DC voltage of input；Power inverting unit, for being three level DC voltage by described photovoltaic DC voltage conversion；Hybrid clamp unit, for when power inverting unit exports zero level, afterflow to be carried out to inverter ac side, and will be continuous Stream mid-point voltage is clamped to the half of photovoltaic DC voltage；Filter unit, for carrying out LPF to described three level DC voltage, so as to export sinusoidal voltage.
- 2. Transformer-free single-phase photovoltaic inverter according to claim 1, it is characterised in that：Described energy storage partial pressure list Member includes two input capacitance Cdc1~Cdc2；Wherein, input capacitance Cdc1Positive pole be connected with the positive pole in photovoltaic DC source, input Electric capacity Cdc1Negative pole and input capacitance Cdc2Positive pole be connected, input capacitance Cdc2Negative pole be connected with the negative pole in photovoltaic DC source.
- 3. Transformer-free single-phase photovoltaic inverter according to claim 2, it is characterised in that：Described input capacitance Cdc1And Cdc2Formed by an electrochemical capacitor composition or by multiple electrochemical capacitor connection in series-parallel.
- 4. Transformer-free single-phase photovoltaic inverter according to claim 1, it is characterised in that：Described power inverting list Member uses single-phase full bridge inverter structure, and it includes 1~S4 of power switch tube S of the anti-simultaneously diode of four bands；Wherein, power switch Pipe S1 one end is connected with one end of power switch tube S 3 and connects the positive pole in photovoltaic DC source, one end of power switch tube S 2 and work( Rate switching tube S4 one end is connected and connects the negative pole in photovoltaic DC source, the other end and the power switch tube S 2 of power switch tube S 1 The connected first voltage output end as power inverting unit of the other end, the other end and the power switch tube S 4 of power switch tube S 3 The other end be connected second voltage output end as power inverting unit；Four 1~S4 of power switch tube S receive outside and set The standby switch controlling signal provided.
- 5. Transformer-free single-phase photovoltaic inverter according to claim 1, it is characterised in that：Described hybrid clamp list Member includes a power switch tube S 5 and six diode D1~D6；Wherein, one end of power switch tube S 5 and diode D2, D4 Be connected with D6 negative electrode, the other end of power switch pipe is connected with diode D1, D3 and D5 anode, diode D1 negative electrode with Diode D2 anode is connected and connects the first voltage output end of power inverting unit, and diode D3 negative electrode is with diode D4's Anode is connected and connects the second voltage output end of power inverting unit, diode D5 negative electrode and diode D6 anode and energy storage Partial pressure unit is connected to extract the photovoltaic DC voltage of half；Power switch tube S 5 receives the switch control that external equipment provides Signal processed.
- 6. the Transformer-free single-phase photovoltaic inverter according to claim 4 or 5, it is characterised in that：Described power is opened Close Guan Jun and use IGBT.
- 7. Transformer-free single-phase photovoltaic inverter according to claim 1, it is characterised in that：Described filter unit is adopted With symmetric inductor wave filter or symmetric form LCL filter.
- 8. Transformer-free single-phase photovoltaic inverter according to claim 7, it is characterised in that：Described symmetric inductor Wave filter includes two filter inductance L1~L2；Wherein, filter inductance L1The first voltage of one end and power inverting unit export End is connected, filter inductance L2One end be connected with the second voltage output end of power inverting unit, filter inductance L1And L2It is another The described sinusoidal voltage of end output.
- 9. Transformer-free single-phase photovoltaic inverter according to claim 7, it is characterised in that：Described symmetric form LCL Wave filter includes two filter inductance L1~L2With a filter capacitor C；Wherein, filter inductance L1One end and power inverting list The first voltage output end of member is connected, filter inductance L2One end be connected with the second voltage output end of power inverting unit, filter Ripple inductance L1And L2The other end be connected respectively with filter capacitor C both ends and export described sinusoidal voltage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710964980.0A CN107834888A (en) | 2017-10-17 | 2017-10-17 | A kind of Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710964980.0A CN107834888A (en) | 2017-10-17 | 2017-10-17 | A kind of Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp |
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| Publication Number | Publication Date |
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| CN107834888A true CN107834888A (en) | 2018-03-23 |
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| CN201710964980.0A Withdrawn CN107834888A (en) | 2017-10-17 | 2017-10-17 | A kind of Transformer-free single-phase photovoltaic inverter of voltage hybrid clamp |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020068022A3 (en) * | 2018-09-29 | 2020-05-07 | Dokuz Eylül Üni̇versi̇tesi̇ Rektörlüğü | A single phase inverter for photovoltaic panels |
| CN111224575A (en) * | 2020-01-15 | 2020-06-02 | 北京天岳京成电子科技有限公司 | Inverter circuit |
| WO2021103842A1 (en) * | 2019-11-26 | 2021-06-03 | 湖南大学 | Gating unit and efficient non-isolated three-level grid-connected inverter |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104065293A (en) * | 2014-05-30 | 2014-09-24 | 浙江大学 | Transformer-free type single-phase photovoltaic inverter with mixed voltage clamping |
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2017
- 2017-10-17 CN CN201710964980.0A patent/CN107834888A/en not_active Withdrawn
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104065293A (en) * | 2014-05-30 | 2014-09-24 | 浙江大学 | Transformer-free type single-phase photovoltaic inverter with mixed voltage clamping |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020068022A3 (en) * | 2018-09-29 | 2020-05-07 | Dokuz Eylül Üni̇versi̇tesi̇ Rektörlüğü | A single phase inverter for photovoltaic panels |
| WO2021103842A1 (en) * | 2019-11-26 | 2021-06-03 | 湖南大学 | Gating unit and efficient non-isolated three-level grid-connected inverter |
| CN111224575A (en) * | 2020-01-15 | 2020-06-02 | 北京天岳京成电子科技有限公司 | Inverter circuit |
| CN111224575B (en) * | 2020-01-15 | 2020-11-20 | 济南星火技术发展有限公司 | Inverter circuit |
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