CN110336325A - A kind of control method and device based on the grid-connected topology of New single-phase - Google Patents
A kind of control method and device based on the grid-connected topology of New single-phase Download PDFInfo
- Publication number
- CN110336325A CN110336325A CN201910650682.3A CN201910650682A CN110336325A CN 110336325 A CN110336325 A CN 110336325A CN 201910650682 A CN201910650682 A CN 201910650682A CN 110336325 A CN110336325 A CN 110336325A
- Authority
- CN
- China
- Prior art keywords
- power
- transformer
- phase
- boost
- mode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 17
- 230000008859 change Effects 0.000 claims description 15
- 239000003990 capacitor Substances 0.000 claims description 9
- 230000010363 phase shift Effects 0.000 claims description 8
- 230000006641 stabilisation Effects 0.000 claims description 5
- 238000011105 stabilization Methods 0.000 claims description 5
- 230000009466 transformation Effects 0.000 claims 2
- 238000010586 diagram Methods 0.000 description 15
- 238000006243 chemical reaction Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 230000005611 electricity Effects 0.000 description 5
- 238000010248 power generation Methods 0.000 description 5
- 238000004088 simulation Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000005286 illumination Methods 0.000 description 3
- 230000001965 increasing effect Effects 0.000 description 3
- 230000001939 inductive effect Effects 0.000 description 3
- 238000002955 isolation Methods 0.000 description 3
- 230000002441 reversible effect Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000011217 control strategy Methods 0.000 description 2
- 238000009795 derivation Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000036961 partial effect Effects 0.000 description 2
- 230000010349 pulsation Effects 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 230000002829 reductive effect Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000013528 artificial neural network Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 230000035800 maturation Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- H02J3/385—
-
- 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
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
- H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac 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
- H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac 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
- H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac 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 with automatic control of output voltage or current, e.g. switching regulators
- H02M3/158—Conversion of dc power input into dc power output without intermediate conversion into ac 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 with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
- H02M3/1584—Conversion of dc power input into dc power output without intermediate conversion into ac 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 with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load with a plurality of power processing stages connected in parallel
-
- 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
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
- H02M3/33576—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
-
- 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
- H02M1/0067—Converter structures employing plural converter units, other than for parallel operation of the units on a single load
- H02M1/007—Plural converter units in cascade
-
- 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
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
- H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac 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
- H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac 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
- H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac 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 with automatic control of output voltage or current, e.g. switching regulators
- H02M3/158—Conversion of dc power input into dc power output without intermediate conversion into ac 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 with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
- H02M3/1584—Conversion of dc power input into dc power output without intermediate conversion into ac 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 with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load with a plurality of power processing stages connected in parallel
- H02M3/1586—Conversion of dc power input into dc power output without intermediate conversion into ac 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 with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load with a plurality of power processing stages connected in parallel switched with a phase shift, i.e. interleaved
-
- 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
-
- 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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P80/00—Climate change mitigation technologies for sector-wide applications
- Y02P80/20—Climate change mitigation technologies for sector-wide applications using renewable energy
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The present invention relates to a kind of control methods and device based on the grid-connected topology of New single-phase, using efficient crisscross parallel type boost structure as prime, centre is shown, mentioned structure is simple and efficient, industrial application value with higher using having the double active bridges of electric power electric transformer efficiently controllable and that front and back function is isolated as output control finally by simulating, verifying, from result.
Description
Technical field
The present invention relates to field of photovoltaic power generation more particularly to a kind of control methods based on the grid-connected topology of New single-phase
With device.
Background technique
The every aspect of the modern life will nearly all rely on electric power, focus on problem that fossil energy generation technology comes
Through highlighting.As photovoltaic power generation is increasingly taken seriously, increasingly higher demands also proposed to photovoltaic interface device, in order into
Step improves transfer efficiency and controllability, lot of domestic and foreign scholar and expands a series of research, and achieve it is abundant at
Fruit.For this purpose, photovoltaic power generation engineering quickly develops into the mainstream of generation of electricity by new energy.
Photovoltaic array by physical structure and the difference of single-die photovoltaic cell etc. external voltage is shown it is non-linear
Characteristic and these factors such as different intensities of illumination and environment temperature will cause the power difference of photovoltaic array, it is therefore desirable to
Using maximum power point tracking technology (Maximum power point tracking, MPPT), such algorithm is by relatively
For maturation, at present mainstream such as perturbation observation method, conductance increment method and fuzzy algorithmic approach, neural network algorithm and derivative one
A little intelligent algorithms etc..
Past is electrically connected between most of photovoltaic systems and power grid using Industrial Frequency Transformer.Industrial Frequency Transformer not only body
Product is big, difficult to install, and cost is high.Fig. 1 describes typical photovoltaic interface block diagram in the prior art；Canonical topology is as schemed
Shown in 1 (a).The advantages such as the non-isolated photovoltaic DC-to-AC converter of transless, which has, realizes high efficiency potentiality, and size is small, but its system exists
Leakage current, although lot of domestic and foreign scholar is deeply divided for non-isolation type photovoltaic parallel in system common mode current producing cause
Analysis, it is indicated that improving circuit topology is the important channel realizing common mode leakage current and effectively inhibiting.But all rest on substantially traditional H5,
The topological structures such as H6, Heric.Therefore, it is grid-connected to seriously affect photovoltaic generating system stability and high efficiency for non-isolation type photovoltaic parallel in system
Operation.In order to be further reduced size, the photovoltaic system band transformer isolation system of weight and economic cost, by traditional power frequency
Transformer has been replaced as the DC side high frequency transformer of small in volume.Not only effectively overcome traditional Industrial Frequency Transformer
Defect, the generation of leakage current.Especially Development of Power Electronic Technology, product have also come into market from laboratory in recent years.It is typical
Topology is as shown in Fig. 1 (c).
It summarizes the above three classes form topology feature and can be found that and following problems exist in the prior art:
(1) topological structure power transmission link is more, reduces system entirety generating efficiency.
(2) photovoltaic cell can not be directly connected directly with conversion stages, need to pass through DC-DC link, most of at present to be
This link is completed using boost structure, photovoltaic cell voltage is with extraneous light emission strength fluctuation.MPPT control need to be introduced.And
In the case that when input terminal voltage is lower, power is constant, input current increases boost circuit, brings biggish line loss.
(3) it is limited to power switch tube constraint, is not suitable for larger large-power occasions under the above three classes topology single-stage.
Summary of the invention
The present invention is used as solving the above problem in the prior art, and primary study topological structure is disturbed using mature
Dynamic observation.By certain control strategy, power conversion efficiency (pce) is improved, additional power conversion link is reduced.
To achieve the goals above, in the first aspect of the invention, it provides a kind of grid-connected based on New single-phase
The control method of topology, wherein using efficient crisscross parallel type boost structure as prime, centre uses the topological structure
It is controlled with the double active bridges of electric power electric transformer efficient controllable and that front and back function is isolated as output, which is characterized in that
Further comprise:
For prime using two-phase interleaved operation Boost circuit as photovoltaic cell interface circuit, two-way Boost structure is in parallel,
Two-way power-sharing reduces the switch stress that power tube is born；
The double active bridges of the electric power electric transformer are to be made up of two H bridges high frequency transformer interconnection, power electronics
The double active full symmetric structures of bridge DAB converter of transformer with intermediate high frequency transformer be it is symmetrical, double active bridge transimission powers with
Phase shifting angle variation and change, when phase shifting angle is 0.5, transimission power reaches maximum, and the phase shifting angle of general double active bridges controls
In d ∈ [0,0.5] section, to guarantee the stabilization of system；
The voltage u electric current i that control system obtains photovoltaic array first obtains crest voltage and reference electricity by MPPT algorithm
Pressure ratio relatively passes through PI controller and obtains PWM duty cycle control signal, to control the PWM generator of a pair of of complementation, driving interlocks
Boost converter link；
Then output DC voltage obtains DAB phase shift with staggeredly PI controller of the boost output voltage Jing Guo control system
Angle controls signal.
Further, it is connected using structure with two-way Boost parallel connection identical in parameter, and two
The conduction phase of power switch tube differs 180 °, realizes paralleling and interleaving operation；It is every all to work independently all the way under crisscross parallel mode
It works in high-power range under discontinuous mode, or works under continuous input pattern.
Further, the work of Boost circuit is in duty ratio D > 0.5, according to switching tube in a switch periods
Four operating modes can be divided into the working condition of diode.Operating mode one: only switching tube S1 and S2 ON operation；Work
Mode two: only switching tube S1 and diode D2 ON operation；Operating mode three: only switching tube S1 and S2 ON operation；Working mould
Formula four: only switching tube S2 and diode D1 ON operation；
The state equation of D > 0.5 is as follows:
One equation of mode are as follows:
Two equation of mode are as follows:
Three equation of mode are as follows:
Four equation of mode are as follows:
Further, double active bridge DAB converters use pulse width modulation algorithm or phase shift modulation algorithm；Using identical duty
While than for 50% changeless pulse for driving two H bridges to generate high frequency square wave, by changing H bridge arm phase offset
Size and Orientation, to change the direction of flow of power and the size of output voltage.
Further, the double active bridges of electric power electric transformer are to be made up of two H bridges high frequency transformer interconnection；Such as figure
Shown in 7；S1-S8IGBT switching tube, D1-D8 are the equivalent body diode of switching tube；C1 and C2 is respectively the primary side of DAB converter
Direct current input capacitance and secondary side direct current output capacitor；I is the electric current that transformer leakage inductance electric current flows through line equivalent inductance；Ls is
Transformer leakage inductance electric current flows through the electric current of line equivalent inductance；Uab and Ucd is respectively the output electricity of DAB converter primary side H bridge
The input voltage of pressure and DAB converter secondary side H bridge；N is the no-load voltage ratio of transformer.
The present invention also provides a kind of control devices based on the grid-connected topology of New single-phase, wherein the topology knot
Using efficient crisscross parallel type boost structure as prime, centre uses to be had efficiently controllable and front and back function is isolated structure
The double active bridges of electric power electric transformer are as output control, which is characterized in that further comprise:
For prime using two-phase interleaved operation Boost circuit as photovoltaic cell interface circuit, two-way Boost structure is in parallel,
Two-way power-sharing reduces the switch stress that power tube is born；
The double active bridges of the electric power electric transformer are to be made up of two H bridges high frequency transformer interconnection, power electronics
The double active full symmetric structures of bridge DAB converter of transformer with intermediate high frequency transformer be it is symmetrical, double active bridge transimission powers with
Phase shifting angle variation and change, when phase shifting angle is 0.5, transimission power reaches maximum, and the phase shifting angle of general double active bridges controls
In d ∈ [0,0.5] section, to guarantee the stabilization of system；
The voltage u electric current i that control system obtains photovoltaic array first obtains crest voltage and reference electricity by MPPT algorithm
Pressure ratio relatively passes through PI controller and obtains PWM duty cycle control signal, to control the PWM generator of a pair of of complementation, driving interlocks
Boost converter link；
Then output DC voltage obtains DAB phase shift with staggeredly PI controller of the boost output voltage Jing Guo control system
Angle controls signal.
Further, it is connected using structure with two-way Boost parallel connection identical in parameter, and two
The conduction phase of power switch tube differs 180 °, realizes paralleling and interleaving operation；It is every all to work independently all the way under crisscross parallel mode
It works in high-power range under discontinuous mode, or works under continuous input pattern.
Further, the work of Boost circuit is in duty ratio D > 0.5, according to switching tube in a switch periods
Four operating modes can be divided into the working condition of diode.Operating mode one: only switching tube S1 and S2 ON operation；Work
Mode two: only switching tube S1 and diode D2 ON operation；Operating mode three: only switching tube S1 and S2 ON operation；Working mould
Formula four: only switching tube S2 and diode D1 ON operation；
The state equation of D > 0.5 is as follows:
One equation of mode are as follows:
Two equation of mode are as follows:
Three equation of mode are as follows:
Four equation of mode are as follows:
Further, double active bridge DAB converters use pulse width modulation algorithm or phase shift modulation algorithm；Using identical duty
While than for 50% changeless pulse for driving two H bridges to generate high frequency square wave, by changing H bridge arm phase offset
Size and Orientation, to change the direction of flow of power and the size of output voltage.
Further, the double active bridges of electric power electric transformer are to be made up of two H bridges high frequency transformer interconnection；Such as figure
Shown in 7；S1-S8IGBT switching tube, D1-D8 are the equivalent body diode of switching tube；C1 and C2 is respectively the primary side of DAB converter
Direct current input capacitance and secondary side direct current output capacitor；I is the electric current that transformer leakage inductance electric current flows through line equivalent inductance；Ls is
Transformer leakage inductance electric current flows through the electric current of line equivalent inductance；Uab and Ucd is respectively the output electricity of DAB converter primary side H bridge
The input voltage of pressure and DAB converter secondary side H bridge；N is the no-load voltage ratio of transformer.
The invention has the following advantages that
1) cascade mode is used, output power can be increased, however if Industrial Frequency Transformer leading portion cascade module, it needs
Increase Industrial Frequency Transformer first side winding coil, or use DC bus parallel form, generates circulation between module, and how
The balance of DC bus-bar voltage is maintained, while also increasing the complexity of control system.
2) stage type structure is used.Prime uses efficient crisscross parallel type DC/DC converter, the function of DC/DC converter
It is to execute MPPT algorithm by controlling its input terminal voltage.By photovoltaic interface prime DC/DC link using efficient and tool
There is the staggered-parallel-type Boost of harmonic inhibition capability, middle layer uses double active bridge structures of electric power electric transformer
Carry out power transmission and electric isolution.By certain control strategies, double active bridges are driven, power conversion efficiency (pce) is further increased,
Reduce additional power conversion link.
Detailed description of the invention
Now, the various aspects below with reference to attached drawing for the preferred embodiment of the present invention describe the present invention, in attached drawing
In:
Fig. 1 is typical photovoltaic interface block diagram in the prior art；
Fig. 2 is photovoltaic cell list diode equivalent circuit model schematic diagram；
Fig. 3 is output characteristic curve schematic diagram of the photovoltaic array under different light irradiances；
Fig. 4 is Boost circuit structural schematic diagram traditional in the prior art；
Fig. 5 is the DC-DC boost converter schematic diagram that interlocks in the present invention；
Fig. 6 is Interleaving and Transformer Paralleling desired output current schematic diagram；
Fig. 7 is double active bridge DC-DC converter topological structure schematic diagrames；
Fig. 8 is single phase shifting control waveform diagram under perfect condition；
Fig. 9 is system control block figure of the invention；
Figure 10 is boost output voltage schematic diagram；
Figure 11 is that Boost exports current diagram；
Figure 12 is double active bridge simulation waveform schematic diagrames；
Figure 13 is double active bridge simulation waveform partial enlargement diagrams；
Figure 14 is double active bridge output voltage schematic diagrames.
Specific embodiment
Now with detailed reference to the embodiment of the present invention, their example is shown in the attached drawings, wherein identical reference
Numerals indicate identical element.In this regard, the embodiment of the present invention can have different forms, and should not be by
It is considered limited to description given here.Therefore, to describe these embodiments below with reference to attached drawing of the invention only for illustrating
Various aspects.
In the following, the explanation that exemplary embodiment of the present invention will be made with reference to attached drawing.
Photovoltaic cell is that luminous energy is turned using photovoltaic effect (photovoltaic effect, also known as photovoltaic effect)
It is changed to the device of electric energy.Photovoltaic effect refers to that, when object is by illumination, the intracorporal charge distribution state of object changes and produces
A kind of effect of motional electromotive force and electric current.
The diode equivalent circuit model of the single p-n junction of photovoltaic cell, as shown in Figure 2.
Wherein, U；I is the output voltage and electric current of photovoltaic potential；Iph is photogenerated current, and I0 is P-N junction equivalent diode
Reverse saturation current；UT is temperature potential；Wherein UT=AkT/q, wherein q is electronic charge (1.602 × 10-19C), A
For P-N junction equivalent diode ideal factor, general value range is 1~1.25；T is photovoltaic battery temperature, Boltzman constant
(1.38x10-23J/K)Rsh；Rs is respectively equivalent series resistance and equivalent parallel resistance.Its forward direction work U-I characteristic equation is such as
Shown in formula (1).
Fig. 3 be photovoltaic array under different illumination and U-I, U-P output characteristic curve.
Boost topology is widely used to AC-DC and DC-DC variation link under various fields, with new energy
Development, mature boost converter is widely used in the front end boosting of photovoltaic generating system, and maintains DC voltage
Stablize.Traditional boost circuit structure is as shown in Figure 4；
It is made of two DC capacitors C1 and C2, inductance Ls, and switch tube device S1, by the duty for changing switching tube
Than to change output voltage.The features such as although circuit is simple and control is easy to accomplish, there are higher EMI for the structure
Interfere and as the reverse recovery time switching device of booster diode under hard switching caused by switching loss, being all can not
Ignore.Especially photovoltaic cell, due to itself belonging to nonlinear system, how reducing interference and improving electric energy and provide efficiency is two
A important indicator, while it being confined to power switch tube, it is unable to satisfy place needed for high and medium power.Therefore the present invention uses two-phase
Interleaved operation Boost circuit is as photovoltaic cell interface circuit, and topological structure is as shown in figure 5, using complete in structure and parameter
Identical two-way Boost parallel connection is connected, and the conduction phase of two power switch tubes differs 180 °, realizes in parallel
Interleaved operation.
From structure, identical two-way Boost structure is in parallel, by the mono- power tube of tradition Boost originally, is changed into two
Road power-sharing reduces the switch stress that power tube is born, the large-power occasions being more suitable under photovoltaic power generation.And due to
Using interleaved parallel mode, improves output electric current and comment rate, reduce filter condenser capacity, reduce since device bring is damaged
Consumption.
It, can also per work in high-power range can be independently operated under discontinuous mode all the way under crisscross parallel mode
To work under continuous input pattern, significantly reduce magnetic discrete component, and effectively inhibit in high-power orientation
The power loss generated during diode reverse recovery.And it is largely obtained in system reliability and fault-tolerance
Improve.
Various voltage relationships and current relationship of the Boost work in stable state can be by states under continuous mode
Vector space method is derived from.Same method is also used herein derives that the Boost circuit of two-phase interleaved operation is accounting for
The relationship of sky ratio D.Boost circuit is using conduction ratio D=0.5 as critical condition when crisscross parallel, and wherein D=0.5 is best work
Make state, wherein the photovoltaic MPPT research based on crisscross parallel Boost circuit will be classified as 3 kinds of D < 0.5, D > 0.5 and D=
0.5.Solar power generation operates mainly in the state of D > 0.5, below by taking D > 0.5 as an example, derive various film relationships and
Mathematical description relationship.
Circuit works in duty ratio D > 0.5, can according to the working condition of switching tube and diode in a switch periods
To be divided into four operating modes.
Operating mode one: only switching tube S1 and S2 ON operation；
Operating mode two: only switching tube S1 and diode D2 ON operation；
Operating mode three: only switching tube S1 and S2 ON operation；
Operating mode four: only switching tube S2 and diode D1 ON operation.
It finally can be obtained by the no-load voltage ratio relational expression of input and output voltage；
The state equation of D > 0.5 is as follows:
One equation of mode are as follows:
Two equation of mode are as follows:
Three equation of mode are as follows:
Four equation of mode are as follows:
It can be obtained according to the volt-second characteristic of inductance L1 and L2 in a cycle:
Similarly it is known that volt-second characteristic when D < 0.5 and D=0.5 is similarly formula (5).
By derivation above it is found that as D > 0.5, D < 0.5 and D=0.5 two-phase crisscross parallel Boost circuit output
The relationship of voltage and input voltage is
It may further derive that inductive current mathematics of the alternating expression parallel connection Boost work under continuous state is retouched
State equation, it is contemplated that the derivation process of duty ratio D > 0.5 is similar with D≤0.5, so the present invention specifically analyze D≤
0.5 the case where, finally gives the result of D > 0.5.Ideal waveform is as shown in Figure 6.Single inductive current pulsation is indicated with Im
Peak value, then；
ILvp-p=ILmax-ILmin (8)
Work as t=t0+DTsWhen TsFor the switch periods of converter, then；
Similarly in lower half period:
Finally converter is arranged in T according to formula (9) (10)sInductive current expression formula in a cycle are as follows:
In summary it is found that two-phase crisscross parallel Boost circuit is more suitable the characteristics of two-phase crisscross parallel Boost circuit
It is applied in photovoltaic maximal power tracing.
As shown in Figure 7；The double active bridges of electric power electric transformer are to be made up of two H bridges high frequency transformer interconnection.S1-
S8IGBT switching tube, D1-D8 are the equivalent body diode of switching tube；C1 and C2 is respectively the primary side direct current input of DAB converter
Capacitor and secondary side direct current output capacitor；I is the electric current that transformer leakage inductance electric current flows through line equivalent inductance；Ls is transformer leakage
Inducing current flows through the electric current of line equivalent inductance；Uab and Ucd is respectively the output voltage and DAB of DAB converter primary side H bridge
The input voltage of converter secondary side H bridge；N is the no-load voltage ratio of transformer.
The double active full symmetric structures of bridge DAB converter of electric power electric transformer with intermediate high frequency transformer be it is symmetrical, one
As there are two types of basic modulation algorithm: pulse width modulation algorithm and phase shift modulation algorithm.Phase shifting control is simply and readily real due to controlling
Now favored, therefore the present invention is using single phase shifting control.Using same duty cycle is 50% changeless pulse for driving
While dynamic two H bridges generate high frequency square wave, by changing the size and Orientation of H bridge arm phase offset, to change power flow
The size in dynamic direction and output voltage.Fig. 8 is DAB voltage current waveform under phase shifting control single under perfect condition.
Wherein；T is the half of switch periods, and d is the amount of phase shift of primary side and secondary side driving pulse, wherein d=ton/T,
And 0 < d < 1.
Therefore, in the steady state, the transimission power of double active bridges may be expressed as:
By formula it is found that double active bridge transimission powers change as phase shifting angle changes, when phase shifting angle is 0.5, function is transmitted
Rate reaches maximum, and the phase shifting angle of general double active bridges controls in d ∈ [0,0.5] section, to guarantee the stabilization of system.
Since photovoltaic cell can generate peak value with the variation of environment, in order to further increase photovoltaic system generating efficiency
Present invention introduces MPPT control, the present invention uses more mature P&O.Control system architecture block diagram is as shown in Fig. 9 top half.
The voltage u electric current i for obtaining photovoltaic array first obtains crest voltage by MPPT algorithm and is controlled compared with reference voltage by PI
Device obtains PWM duty cycle and controls signal, to control the PWM generator of a pair of of complementation, drives boost converter link of interlocking.
As shown in the lower half Fig. 9, output DC voltage is controlled with staggeredly boost output voltage by PI DAB controlling unit
Device obtains DAB phase shifting angle control signal.
Finally, carrying out simulating, verifying by the above-mentioned analysis of simulating, verifying using Matlab, choosing simulation parameter such as table 1-2
It is shown；
Table 1
Table 2
Figure 10 is boost output voltage, is significantly less than using the fluctuation of crisscross parallel boost output voltage adopts as shown in the figure
With traditional boost output voltage, the effective stability for inhibiting harmonic wave to improve voltage reduces the direct current capacitors of DC side
Capacitance, so that progress one reduces capacitor volume.
Boost output electric current is as shown in figure 11, further can be seen that electric current is more smooth obvious small from the medium and small figure of figure
Output current wave under traditional boost structure.
From Figure 10-11 simulation result it is found that demonstrating content analyzed above, from structure, crisscross parallel type boost is more
It is suitble to photovoltaic interface.
The present invention is using unilateral two-track phase control, the double active each key point output waveform such as Figure 12 of bridge of electric power electric transformer
It is shown.
It is waveform partially enlarged in Figure 11 is as shown in figure 13, it can be seen that one secondary side output waveform of transformer is presented
Preferable pulsation.
The finally output voltage waveforms of the double active bridges of observation electric power electric transformer, as shown in figure 14 it can be seen that waveform compared with
It can be seen that amplitude that voltage or more fluctuates substantially close to reference voltage for smooth and fast response time, from partial enlargement.
The present invention proposes a kind of novel photovoltaic interface topological structure on the basis of conventional photovoltaic interface.Using height
Crisscross parallel type boost structure is imitated as prime, centre is using with power electronics efficient controllable and that front and back function is isolated
The double active bridges of transformer show, mentioned structure is simple and efficient, has as output control finally by simulating, verifying, from result
There is higher industrial application value.
Although embodiment disclosed by the application is as above, the content only for ease of understanding the application and use
Embodiment is not limited to the application, such as the concrete implementation method in embodiment of the present invention.Belonging to any the application
Technical staff in field, under the premise of not departing from spirit and scope disclosed by the application, can implementation form and
Any modification and variation, but the scope of patent protection of the application are carried out in details, it still must be with appended claims institute circle
Subject to fixed range.
The above is a preferred embodiment of the present invention, it is noted that for those skilled in the art
For, without departing from the principles of the present invention, it can also make several improvements and retouch, these improvements and modifications
It should be regarded as protection scope of the present invention.
Claims (10)
1. a kind of control method based on the grid-connected topology of New single-phase, wherein the topological structure is interlocked simultaneously using efficient
Connection type boost structure is as prime, and centre is using double with electric power electric transformer efficient controllable and that front and back function is isolated
Active bridge is as output control, which is characterized in that further comprises:
Prime is using two-phase interleaved operation Boost circuit as photovoltaic cell interface circuit, and two-way Boost structure is in parallel, two-way
Power-sharing reduces the switch stress that power tube is born；
The double active bridges of the electric power electric transformer are to be made up of two H bridges high frequency transformer interconnection, power electronics transformation
The double active full symmetric structures of bridge DAB converter of device with intermediate high frequency transformer be it is symmetrical, double active bridge transimission powers are with shifting
Phase angle change and change, when phase shifting angle is 0.5, transimission power reaches maximum, and the phase shifting angle of general double active bridges is controlled in d ∈
In [0,0.5] section, to guarantee the stabilization of system；
The voltage u electric current i that control system obtains photovoltaic array first obtains crest voltage and reference voltage ratio by MPPT algorithm
Relatively pass through PI controller acquisition PWM duty cycle and control signal, to control the PWM generator of a pair of of complementation, drives staggeredly boost
Converter link；
Then output DC voltage obtains DAB phase shifting angle control with staggeredly PI controller of the boost output voltage Jing Guo control system
Signal processed.
2. the method according to claim 1, wherein using identical two-way Boost in structure and parameter
Converter parallel connection is connected, and the conduction phase of two power switch tubes differs 180 °, realizes paralleling and interleaving operation；Staggeredly simultaneously
Under connection mode, work per being all independently operated under discontinuous mode all the way in high-power range, or the work under continuous input pattern
Make.
3. according to the method described in claim 2, it is characterized in that, Boost circuit work in duty ratio D > 0.5,
Four operating modes can be divided into according to the working condition of switching tube and diode in one switch periods.Operating mode one: only
Switching tube S1 and S2 ON operation；Operating mode two: only switching tube S1 and diode D2 ON operation；Operating mode three: it only opens
Close pipe S1 and S2 ON operation；Operating mode four: only switching tube S2 and diode D1 ON operation；
The state equation of D > 0.5 is as follows:
One equation of mode are as follows:
Two equation of mode are as follows:
Three equation of mode are as follows:
Four equation of mode are as follows:
4. according to the method described in claim 3, it is characterized in that, double active bridge DAB converters using pulse width modulation algorithm or
Phase shift modulation algorithm；Same duty cycle is used to be used to that two H bridges be driven to generate high frequency square wave for 50% changeless pulse
Meanwhile by change H bridge arm phase offset size and Orientation, thus change flow of power direction and output voltage it is big
It is small.
5. according to the method described in claim 3, it is characterized in that, the double active bridges of electric power electric transformer are led to by two H bridges
High frequency transformer interconnection is crossed to constitute；As shown in Figure 7；S1-S8 IGBT switching tube, D1-D8 are the equivalent body diode of switching tube；C1
It is respectively the primary side direct current input capacitance and secondary side direct current output capacitor of DAB converter with C2；I is transformer leakage inductance electric current
Flow through the electric current of line equivalent inductance；Ls is the electric current that transformer leakage inductance electric current flows through line equivalent inductance；Uab and Ucd difference
For the output voltage of DAB converter primary side H bridge and the input voltage of DAB converter secondary side H bridge；N is the no-load voltage ratio of transformer.
6. a kind of control device based on the grid-connected topology of New single-phase, wherein the topological structure is interlocked simultaneously using efficient
Connection type boost structure is as prime, and centre is using double with electric power electric transformer efficient controllable and that front and back function is isolated
Active bridge is as output control, which is characterized in that further comprises:
Prime is using two-phase interleaved operation Boost circuit as photovoltaic cell interface circuit, and two-way Boost structure is in parallel, two-way
Power-sharing reduces the switch stress that power tube is born；
The double active bridges of the electric power electric transformer are to be made up of two H bridges high frequency transformer interconnection, power electronics transformation
The double active full symmetric structures of bridge DAB converter of device with intermediate high frequency transformer be it is symmetrical, double active bridge transimission powers are with shifting
Phase angle change and change, when phase shifting angle is 0.5, transimission power reaches maximum, and the phase shifting angle of general double active bridges is controlled in d ∈
In [0,0.5] section, to guarantee the stabilization of system；
The voltage u electric current i that control system obtains photovoltaic array first obtains crest voltage and reference voltage ratio by MPPT algorithm
Relatively pass through PI controller acquisition PWM duty cycle and control signal, to control the PWM generator of a pair of of complementation, drives staggeredly boost
Converter link；
Then output DC voltage obtains DAB phase shifting angle control with staggeredly PI controller of the boost output voltage Jing Guo control system
Signal processed.
7. device according to claim 6, which is characterized in that using identical two-way Boost in structure and parameter
Converter parallel connection is connected, and the conduction phase of two power switch tubes differs 180 °, realizes paralleling and interleaving operation；Staggeredly simultaneously
Under connection mode, work per being all independently operated under discontinuous mode all the way in high-power range, or the work under continuous input pattern
Make.
8. device according to claim 7, which is characterized in that Boost circuit works in duty ratio D > 0.5,
Four operating modes can be divided into according to the working condition of switching tube and diode in one switch periods.Operating mode one: only
Switching tube S1 and S2 ON operation；Operating mode two: only switching tube S1 and diode D2 ON operation；Operating mode three: it only opens
Close pipe S1 and S2 ON operation；Operating mode four: only switching tube S2 and diode D1 ON operation；
The state equation of D > 0.5 is as follows:
One equation of mode are as follows:
Two equation of mode are as follows:
Three equation of mode are as follows:
Four equation of mode are as follows:
9. device according to claim 8, which is characterized in that double active bridge DAB converters using pulse width modulation algorithm or
Phase shift modulation algorithm；Same duty cycle is used to be used to that two H bridges be driven to generate high frequency square wave for 50% changeless pulse
Meanwhile by change H bridge arm phase offset size and Orientation, thus change flow of power direction and output voltage it is big
It is small.
10. device according to claim 8, which is characterized in that the double active bridges of electric power electric transformer are led to by two H bridges
High frequency transformer interconnection is crossed to constitute；As shown in Figure 7；S1-S8 IGBT switching tube, D1-D8 are the equivalent body diode of switching tube；C1
It is respectively the primary side direct current input capacitance and secondary side direct current output capacitor of DAB converter with C2；I is transformer leakage inductance electric current
Flow through the electric current of line equivalent inductance；Ls is the electric current that transformer leakage inductance electric current flows through line equivalent inductance；Uab and Ucd difference
For the output voltage of DAB converter primary side H bridge and the input voltage of DAB converter secondary side H bridge；N is the no-load voltage ratio of transformer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910650682.3A CN110336325B (en) | 2019-07-18 | 2019-07-18 | Control method and device based on novel single-phase photovoltaic grid-connected topology |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910650682.3A CN110336325B (en) | 2019-07-18 | 2019-07-18 | Control method and device based on novel single-phase photovoltaic grid-connected topology |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110336325A true CN110336325A (en) | 2019-10-15 |
| CN110336325B CN110336325B (en) | 2022-12-02 |
Family
ID=68145905
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910650682.3A Active CN110336325B (en) | 2019-07-18 | 2019-07-18 | Control method and device based on novel single-phase photovoltaic grid-connected topology |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110336325B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111030483A (en) * | 2019-12-30 | 2020-04-17 | 上海科梁信息工程股份有限公司 | Power electronic transformer and control method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102097966A (en) * | 2011-02-14 | 2011-06-15 | 东南大学 | Cascade megawatt photovoltaic grid-connected inverter |
| WO2016015329A1 (en) * | 2014-08-01 | 2016-02-04 | 冷再兴 | Dc-ac bi-directional power converter topology |
| CN107124115A (en) * | 2017-06-16 | 2017-09-01 | 特变电工新疆新能源股份有限公司 | A kind of method that solid-state transformer starts |
| US10263456B1 (en) * | 2015-03-13 | 2019-04-16 | The Florida State University Research Foundation, Inc. | Integrated three-port bidirectional DC-DC converter for renewable energy sources |
-
2019
- 2019-07-18 CN CN201910650682.3A patent/CN110336325B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102097966A (en) * | 2011-02-14 | 2011-06-15 | 东南大学 | Cascade megawatt photovoltaic grid-connected inverter |
| WO2016015329A1 (en) * | 2014-08-01 | 2016-02-04 | 冷再兴 | Dc-ac bi-directional power converter topology |
| US10263456B1 (en) * | 2015-03-13 | 2019-04-16 | The Florida State University Research Foundation, Inc. | Integrated three-port bidirectional DC-DC converter for renewable energy sources |
| CN107124115A (en) * | 2017-06-16 | 2017-09-01 | 特变电工新疆新能源股份有限公司 | A kind of method that solid-state transformer starts |
Non-Patent Citations (4)
| Title |
|---|
| MUHAMMAD MUNEEB UR REHMAN；ROHAIL HASSAN；NAUMAN ZAFFAR: "High efficiency modified dual-active bridge converter for photovoltaic integration", 《2013 IEEE GRENOBLE CONFERENCE》 * |
| YANJUN TIAN等: "Active Power and DC Voltage Coordinative Control for Cascaded DC–AC Converter With Bidirectional Power Application", 《IEEE TRANSACTIONS ON POWER ELECTRONICS》 * |
| 乔颖硕等: "光伏MPPT拓扑电路与控制策略仿真研究", 《电源技术》 * |
| 孙孝峰等: "双Buck/Boost集成双有源桥三端口DC-DC变换器", 《电工技术学报》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111030483A (en) * | 2019-12-30 | 2020-04-17 | 上海科梁信息工程股份有限公司 | Power electronic transformer and control method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110336325B (en) | 2022-12-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110365205B (en) | High-efficiency totem-pole bridgeless PFC rectifier control method | |
| CN103618470B (en) | A kind of power decoupled control method based on grid-connected micro-inverter | |
| CN105048490B (en) | The photovoltaic micro-inverter and its numerical control device of low current stress | |
| CN105207256A (en) | Photovoltaic micro inverter | |
| CN109980978B (en) | Converter and modulation method thereof | |
| CN110620377B (en) | Three-port DC-DC converter for energy efficient transmission and control method thereof | |
| CN109067190B (en) | LLC resonant converter of wide gain | |
| Li et al. | A method of power decoupling for long life micro-inverter | |
| CN104410316B (en) | High-frequency link inverter and digital control device thereof | |
| CN105703652A (en) | Control method of high-frequency isolation DC/AC inverter circuit and high-frequency isolation DC/AC inverter circuit | |
| CN104184396A (en) | Photovoltaic power supply system and control method thereof | |
| Yang et al. | Single-phase high-gain bidirectional dc/ac converter based on high step-up/step-down dc/dc converter and dual-input dc/ac converter | |
| CN110829837A (en) | Low-voltage stress ZVS high-gain Boost converter | |
| Marikkannan et al. | ZVS asymmetrical PWM full-bridge high voltage gain DC-DC converter controlled by ANFIS for energy harvesting applications | |
| CN109889036A (en) | A kind of IPOS DC charging power supply for tracking best efficiency point | |
| CN103888013B (en) | The Miniature inverter theoretical based on high-frequency ac blood pressure lowering and numerical control device thereof | |
| Shafeeque et al. | A novel single-phase single-stage inverter for solar applications | |
| CN112165268A (en) | Decoupling circuit and method | |
| CN110336325A (en) | A kind of control method and device based on the grid-connected topology of New single-phase | |
| CN110071652B (en) | Low-leakage-current five-switch non-isolated single-phase photovoltaic grid-connected inverter and grid-connected system | |
| CN117013866A (en) | Single-stage wide-voltage isolation bidirectional AC/DC converter | |
| CN209345007U (en) | Frequency conversion light modulator based on PFC and T-type inverter circuit | |
| CN116827131A (en) | Single-stage isolated bidirectional AC/DC converter | |
| CN116054571A (en) | Alternating parallel three-level soft switch direct current boost converter | |
| CN202524301U (en) | Grid-connected inverter of wind-driven generator |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |