CN107257136B - Grid-connected converter exports phase-locked loop systems and control method - Google Patents
Grid-connected converter exports phase-locked loop systems and control method Download PDFInfo
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- H02J3/382—
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/01—Arrangements for reducing harmonics or ripples
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/26—Arrangements for eliminating or reducing asymmetry in polyphase networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
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- 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
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/40—Arrangements for reducing harmonics
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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
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/50—Arrangements for eliminating or reducing asymmetry in polyphase networks
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Abstract
The invention discloses a kind of grid-connected converter output phase-locked loop systems and control method, the grid-connected converter output phase-locked loop systems include: Clark conversion module, carry out Clark transformation to the three-phase voltage signal of grid-connected converter output；Be delayed cancellation module, carries out delay elimination to the two-phase voltage under α β coordinate system；Park conversion module carries out Park transformation to the two-phase voltage under the α β coordinate system after eliminating delay according to initial output phase；Pi regulator carries out PI adjusting to q axis signal；Integration module carries out Integral Processing to network voltage estimated value to obtain initial output phase；Amplification module adjusts error to frequency and amplifies processing to obtain phase compensation amount；Laminating module is overlapped processing to initial output phase and phase compensation amount to obtain final output phase.Grid-connected converter output phase-locked loop systems provided by the invention and control method can accurately obtain the fundamental frequency and phase information of grid-connected converter output voltage in system voltage imbalance or distortion.
Description
Technical field
The present invention relates to power electronics fields, and in particular to a kind of grid-connected converter output phase-locked loop systems and control
Method.
Background technique
With the development of the Ac/dc Power Systems such as generation of electricity by new energy, microgrid, D.C. high voltage transmission, connect as Power Exchange
The electronic power convertor of mouth is more and more used in the power system.Grid-connected converter is as a kind of important electric power
Electronic device mainly includes wind power-generating grid-connected inverter, photovoltaic combining inverter, the static reacance generation for fundamental wave application
Device and shunt active power filter for power network harmonic wave management.
Network voltage is three-phase symmetrical in the ideal situation, but in actual electric network, often will appear grid voltage three-phase
Imbalance, the small value imbalance including normality are fallen with fault transient state asymmetrical voltage.The unbalance voltage of very little will
The electric current height imbalance and distortion of grid-connected converter are caused, and then DC side busbar voltage is caused to vibrate, influences power grid
Stability.The operation is stable, the rapid fundamental frequency of response and phase tracking system are to ensure that grid-connected converter stable operation
Key mostly uses greatly power frequency software phlase locking algorithm to realize the fundamental frequency and phase real-time detection of network voltage, Ci Zhongfang at present
Method strong interference immunity can obtain ideal detection accuracy without the high-accuracy element of high-precision.Control under being operated normally with power grid
System strategy is similar, and inner loop control of the grid-connected converter under unbalanced power supply state mainly has current control and Direct Power control
System two kinds, generally use inhibit two frequency multiplication of active power pulsation come eliminate DC side busbar voltage second harmonic be control target
Air-blower control strategy.However, delay brought by necessary positive and negative order components separation will make current feedback amount, there are amplitudes and phase
Position error, influences the dynamic property of entire control system.
Summary of the invention
To be solved by this invention is that delay brought by the positive and negative order components separation of grid-connected converter output makes current feedback
There is amplitude and phase error, lead to whole system bad dynamic performance in amount.
The present invention is achieved through the following technical solutions:
A kind of grid-connected converter output phase-locked loop systems, comprising: Clark conversion module, for being exported to grid-connected converter
Three-phase voltage signal carry out Clark convert to obtain the two-phase voltage under α β coordinate system；Be delayed cancellation module, for sitting to α β
Two-phase voltage under mark system carries out delay and eliminates to obtain the two-phase voltage under the α β coordinate system after eliminating delay；Park converts mould
Block is converted for carrying out Park to the two-phase voltage under the α β coordinate system after eliminating delay according to initial output phase to obtain d
Axis signal and q axis signal；Pi regulator is adjusted for carrying out PI to q axis signal to obtain network voltage estimated value and frequency tune
Save error；Integration module, for carrying out Integral Processing to network voltage estimated value to obtain initial output phase；Amplification module,
Processing is amplified for adjusting error to frequency to obtain phase compensation amount；Laminating module, for initial output phase and
Phase compensation amount is overlapped processing to obtain final output phase.
Grid-connected converter output phase-locked loop systems provided by the invention can quickly and accurately extract fundamental positive sequence voltage
Amplitude, phase and frequency, precision and dynamic characteristic are much better than traditional phase locked algorithm.Also, system provided by the invention can be with
It is realized by software programming, strong interference immunity；By using closed-loop control, stability is high, and tracking velocity is very fast, when transient response
Between be less than 20ms, frequency of phase locking range is more wide in range, about 45~60Hz, does not fall etc. operating conditions by the harmonic wave of system voltage and instantaneously
Interference, provide accurate system synchronous phase signal for grid-connected converter.
Optionally, the transmission function of the delay cancellation moduleWherein, n=2mAnd m
For positive integer, s is Complex frequency, and e is natural constant, and j is imaginary unit, T=0.02 seconds.
Optionally, the amplification coefficient of the amplification module
Optionally, the transmission function of the delay cancellation moduleWherein, m
For the positive integer greater than 1, s is Complex frequency, and e is natural constant, and j is imaginary unit, T=0.02 seconds.Due to network voltage
Harmonic content frequency spectrum is wider, and filtering can further be improved by carrying out repeatedly delay Processing for removing to the two-phase voltage under α β coordinate system
Performance.
Optionally, the amplification coefficient of the amplification module
Phase-locked loop systems are exported based on above-mentioned grid-connected converter, the present invention also provides a kind of grid-connected converters to export controlling party
Method, comprising: using DC bus-bar voltage average value as controlled volume, trapper is added in DC voltage feedback channel；Respectively just
Positive-negative sequence current decoupling controller is set under negative phase-sequence dual rotary coordinate system, wherein the instruction of positive sequence watt current is determined by direct current outer ring
Fixed, negative phase-sequence watt current instruction is zero, the idle tune that positive sequence active component instruction is generated according to scheduling reactive voltage control system
Program mark obtain, negative phase-sequence referenced reactive current according toIt obtains,Electric current is exported for grid-connected converter
Negative phase-sequence q axis component,For network voltage negative phase-sequence d axis component,The positive sequence q axis component of electric current is exported for grid-connected converter,For network voltage positive sequence d axis component, ω0For fundamental frequency, LgFor the grid-connected inductance of grid-connected converter；It adjusts and carries out by PI
Current follow-up control, and consider the current decoupled control under dq coordinate system；By the signal obtained after current decoupled control point
It is not overlapped with the component of voltage under positive-negative sequence dual rotary coordinate system, the phase of superimposed signal is claim 1 to 5 times
Grid-connected converter described in one exports the final output phase in phase-locked loop systems；Double coordinates are carried out to superimposed signal to become
It changes to obtain modulated signal, and modulated signal is passed through into the control terminal of the IGBT of PWM transformation output to grid-connected converter.
Grid-connected converter output control method provided by the invention can using positive-negative sequence double-current decoupling control policy
Adaptability of the equipment in unbalanced source voltage where significantly improving grid-connected converter.
Optionally, the centre frequency of the trapper is twice of fundamental frequency.
Optionally, the transmission function of the trapper isWherein, ζ is damped coefficient.
Compared with prior art, the present invention having the following advantages and benefits:
Grid-connected converter output phase-locked loop systems provided by the invention and control method, in system voltage imbalance or distortion
When can accurately obtain the fundamental frequency and phase information of grid-connected converter output voltage, reduce because positive and negative order components separate institute
Bring delay makes amplitude existing for current feedback amount and phase error.The grid-connected converter output control proposed on this basis
Method, using positive-negative sequence double-current decoupling control policy, equipment where grid-connected converter can be significantly improved network voltage not
Adaptability when balance.
Detailed description of the invention
Attached drawing described herein is used to provide to further understand the embodiment of the present invention, constitutes one of the application
Point, do not constitute the restriction to the embodiment of the present invention.In the accompanying drawings:
Fig. 1 is the structural schematic diagram of the grid-connected converter output phase-locked loop systems of the embodiment of the present invention；
Fig. 2 is the frequency characteristic that the embodiment of the present invention carries out delay cancellation module when primary delay Processing for removing；
Fig. 3 is the frequency characteristic that the embodiment of the present invention carries out delay cancellation module when repeatedly delay Processing for removing；
Fig. 4 is the small-signal model of the grid-connected converter output phase-locked loop systems of the embodiment of the present invention；
Fig. 5 is the structural schematic diagram of the grid-connected converter export control policy of the embodiment of the present invention；
Fig. 6 is the effect that phase-locked loop systems export when power grid A phase voltage drops to 0.5p.u. signal of the embodiment of the present invention
Figure；
Fig. 7 is grid-connected converter and generator-side converter wear control when power grid A phase voltage drops to 0.5p.u. of the embodiment of the present invention
Effect diagram processed.
Specific embodiment
To make the objectives, technical solutions, and advantages of the present invention clearer, below with reference to embodiment and attached drawing, to this
Invention is described in further detail, and exemplary embodiment of the invention and its explanation for explaining only the invention, are not made
For limitation of the invention.
Embodiment 1
Fig. 1 is the structural schematic diagram of the grid-connected converter output phase-locked loop systems of the present embodiment, and the grid-connected converter is defeated
Phase-locked loop systems include Clark conversion module 11, delay cancellation module 12, Park conversion module 13, pi regulator 14, integral out
Module 15, amplification module 16 and laminating module 17.
Specifically, the Clark conversion module 11 is used for the three-phase voltage signal v exported to grid-connected convertera、vbAnd
vcClark transformation is carried out to obtain the two-phase voltage v under α β coordinate systemαAnd vβ, i.e., by the three-phase voltage letter of grid-connected converter output
Number va、vbAnd vcIt is downconverted under α β coordinate system from abc coordinate system.The specific reality of Clark transformation as known to those skilled in the art
Existing method, details are not described herein.
The delay cancellation module 12 is used for the two-phase voltage v under α β coordinate systemαAnd vβCarry out delay elimination (DSC,
Delayed Signal Cancellation) to obtain the two-phase voltage under the α β coordinate system after eliminating delayWithThis
Embodiment provides a kind of transmission function of the delay cancellation module 12 are as follows:
Wherein, n is delay factor, n=2mAnd m is positive integer, s is Complex frequency, and e is natural constant, and j is imaginary number list
Position, T=0.02 seconds.The corresponding frequency domain transfer function of the delay cancellation module 12 is as follows:
It can be obtained by formula (2):
Wherein, k=0, ± 1, ± 2, ± 3 ..., G is the amplitude of frequency domain transfer function, and φ is the phase of frequency domain transfer function
Angle, ω are each component frequency of input signal,For fundamental frequency.As n=4, the frequency of the delay cancellation module 12
Rate characteristic curve is as shown in Figure 2.As can be seen that as n=4, the delay cancellation module 12 can effectively filter out 4k-1 times it is humorous
Wave, but 4k+1 subharmonic then has no to decay, and does not have delayed phase and amplitude attenuation to fundamental signal.
It, can be to two under α β coordinate system in order to improve filtering performance since the harmonic content frequency spectrum of network voltage is wider
Phase voltage vαAnd vβRepeatedly delay is carried out to eliminate.Based on this, the present embodiment provides another transmitting of the delay cancellation module 12
Function are as follows:
As m=5, the frequency characteristic of the delay cancellation module 12 is as shown in Figure 3.It is not difficult to find out that the delay
Thus harmonic content is completely eliminated in cancellation module 12 at integral frequency harmonizing wave frequency, improve the control of phase-locked loop systems significantly
Precision.
The Park conversion module 13 is used for according to initial output phaseTo two under the α β coordinate system eliminated after being delayed
Phase voltageWithPark transformation is carried out to obtain d axis signal vdWith q axis signal vq, i.e., will eliminate under the α β coordinate system after being delayed
Two-phase voltageWithIt is downconverted under dq coordinate system from α β coordinate system.The tool of Park transformation as known to those skilled in the art
Body implementation method, details are not described herein.
The pi regulator 14 is used for q axis signal vqPI is carried out to adjust to obtain network voltage estimated value and frequency and adjust
Error delta ωi, the integration module 15 is used to carry out Integral Processing to the network voltage estimated value described initial defeated to obtain
Phase outThe amplification module 16 is used to adjust error delta ω to the frequencyiProcessing is amplified to obtain phase compensation
AmountThe laminating module 17 is used for the initial output phaseWith the phase compensation amountProcessing is overlapped to obtain
Obtain final output phase thetao, the delayed phase effect of the pi regulator 14 passes through the feedforward path that the amplification module 16 is constituted
It compensates.Wherein, the proportionality coefficient k of the pi regulator 14p, the pi regulator 14 integral coefficient kiAnd it described puts
The amplification coefficient of big module 16It can be configured according to actual needs.To the two-phase voltage v under α β coordinate systemαAnd vβIt carries out
For five delays are eliminated, i.e., by taking m=5 as an example, the present embodiment provides a kind of occurrences of above-mentioned parameter.
Firstly, establishing the small-signal model of grid-connected converter output phase-locked loop systems shown in FIG. 1, as shown in Figure 4.Its
In, the transmission function of the delay cancellation module 12 are as follows:
Then based on the closed loop transfer function, of small-signal model are as follows:
Wherein, come approximate, i.e., delay link can be converted with single order Pade are as follows:
Composite type (6) and formula (7), the closed loop transfer function, of phase-locked loop systems provided in this embodiment are as follows:
It enablesAssuming that the phase margin of phase-locked loop systems is 55 °, then k is calculatedp=440, ki
=48361.Wherein, ζ is damped coefficient, and the phase margin of phase-locked loop systems can design between 40 ° to 60 °.
In addition, the amplification coefficient of the amplification module 16 are as follows:
According to the feedforward link can effective compensation time delayed signal eliminate generate phase error, realize network voltage fundamental frequency phase
The accurate tracking of position.
Embodiment 2
Phase-locked loop systems are exported according to the grid-connected converter that embodiment 1 provides, the present embodiment provides one kind in power grid injustice
Grid-connected converter output control method under the conditions of weighing apparatus.When power grid three-phase imbalance, voltage negative sequence component will cause grid-connected
Current transformer exports two double-frequency fluctuation of instantaneous power, and then causes the fluctuation of DC bus-bar voltage.The fluctuation is excessive, can trigger change
Flow overvoltage of direct current/low-voltage protection of device.To avoid above-mentioned phenomenon, needs to export negative-sequence current to grid-connected converter and be controlled
System.
According to instantaneous power theory, grid-connected converter active power of output is calculated are as follows:
Pc=Pc0++Pc0-+P1cos(2ω0t)+P2sin(2ω0T) formula (10)
In formula,
Wherein, Pc0+For average active power positive-sequence component, Pc0-For average active power negative sequence component, P1For 2 times of power frequencies
Active wave component cosine term, P2For the sine term of the active wave component of 2 times of power frequencies,For grid-connected converter exchange
The positive sequence d axis component of outlet side voltage,The positive sequence d axis component of electric current is exported for grid-connected converter,For grid-connected converter
The positive sequence q axis component of outlet side voltage is exchanged,The positive sequence q axis component of electric current is exported for grid-connected converter,For grid-connected change
The negative phase-sequence d axis component of device exchange outlet side voltage is flowed,The negative phase-sequence d axis component of electric current is exported for grid-connected converter,For simultaneously
Net current transformer exchanges the negative phase-sequence q axis component of outlet side voltage,The negative phase-sequence q axis component of electric current is exported for grid-connected converter.
In order to eliminate twice of power frequency fluctuation of DC bus-bar voltage, P need to be met1=P2=0.If defining positive sequence synchronous rotary
The d of coordinate system+Axis is overlapped with positive sequence voltage vector, then network voltage vector d under positive-negative sequence synchronous rotating frameP/qPWith
dN/qNAxis component are as follows:
Wherein,For network voltage positive sequence d axis component,For network voltage positive sequence q axis component,For network voltage
Negative phase-sequence d axis component,For network voltage negative phase-sequence q axis component.
According to principle of stacking, the voltage equation for obtaining positive-sequence component under positive-negative sequence synchronous rotating frame is respectively indicated are as follows:
The voltage equation of negative sequence component respectively indicates under positive-negative sequence synchronous rotating frame are as follows:
Wherein, RgFor the grid-connected resistance of grid-connected converter, LgFor the grid-connected inductance of grid-connected converter.
According to formula (10) to formula (14), the positive-negative sequence double-current ring under the conditions of unbalanced source voltage shown in fig. 5 is established
Control strategy figure.Sufficiently to provide reactive current support for power grid, can be injected according to the requirement of dispatching of power netwoks person or grid-connected directive/guide
Specified positive sequence active component.On this basis, the residual capacity of grid-connected converter is for controlling negative-sequence current component, to reduce
The fluctuation of DC bus-bar voltage.If positive sequence active component instruction is smaller, it is completely eliminated directly by controlling negative-sequence current component
Flow the fluctuation of busbar voltage；It is instructed if biggish positive sequence active component, then using grid-connected converter residual capacity, maximum journey
Reduce DC bus-bar voltage fluctuation in degree ground.
In order to avoid DC voltage fluctuation impacts grid-connected converter output electric current, grid-connected converter is with DC bus
Average voltage UdcFor controlled volume, the trapper that centre frequency is twice of fundamental frequency is added in DC voltage feedback channel,
The transmission function of the trapper isWherein, damping coefficientζ=0.7 of trapper, as shown in Figure 5.
In order to realize the control of grid-connected converter positive-negative sequence current, it is arranged under positive-negative sequence dual rotary coordinate system respectively positive and negative
Sequence current decoupled control device, wherein positive sequence watt current instructionIt is determined by DC voltage control outer ring, negative phase-sequence watt current
InstructionIt is zero, positive sequence active component instructionIt is obtained according to the Reactive-power control target that scheduling reactive voltage control system generates,
Negative phase-sequence referenced reactive currentThen obtain according to the following formula:
Further, it is adjusted by PI and carries out current follow-up control, and consider the current decoupled control under dq coordinate system；It will be through
The signal obtained after overcurrent decoupling control is overlapped with the component of voltage under positive-negative sequence dual rotary coordinate system respectively, after superposition
Signal phase thetaPLLThe final output phase theta in phase-locked loop systems is exported for grid-connected converter described in embodiment 1o；To folded
Signal after adding carries out double coordinate transforms to obtain modulated signal ucαβref, and by modulated signal ucαβrefIt is converted and is exported by PWM
To the control terminal of the IGBT of grid-connected converter.
In order to verify the present embodiment grid-connected converter output control method validity and correctness, Fig. 6 and Fig. 7 difference
For the straight drive blower system effect diagram and grid-connected that phase-locked loop systems export when power grid A phase voltage drops to 0.5p.u.
Current transformer and generator-side converter wear control effect schematic diagram.The waveform of Fig. 6 is followed successively by net side three-phase voltage, locking phase ring system from top to bottom
The fundamental frequency that the positive and negative order components of voltage extracted, phase-locked loop systems extract of uniting and the fundamental phase that phase-locked loop systems extract,
The waveform of Fig. 7 is followed successively by net side three-phase voltage, current on line side, DC capacitor voltage, net side power, pusher side function from top to bottom
Rate, side currents, revolving speed and the speed reference obtained according to maximal power tracing control.
As can be seen from Figures 6 and 7, when power grid A phase voltage drops to 50%, phase-locked loop systems can be extracted accurately
The positive and negative order components of voltage provide voltage fundamental phase information accurately and timely for the controlling unit under synchronous coordinate system.Direct current
Side is stablized near given value 1050V, without two double-frequency fluctuation components.Meanwhile 120 ° of net side three-phase current mutual deviation, three-phase current is abnormal
Variability is smaller, and the active power of output still remains unchanged, and pusher side and the waveform before failure are more consistent.Each electricity from control strategy
From the point of view of the error of flow control ring and DC voltage control ring, although the dq axis reference value of electric current loop after voltage three-phase imbalance occurs
It changes, but the electric current of dq axis remains to track the variation of current reference value, it is ensured that electric current loop stablizes output, while straight
Stream side voltage control is also always maintained at stable operation, and pusher side is without significant change.
Above-described specific embodiment has carried out further the purpose of the present invention, technical scheme and beneficial effects
It is described in detail, it should be understood that being not intended to limit the present invention the foregoing is merely a specific embodiment of the invention
Protection scope, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done should all include
Within protection scope of the present invention.
Claims (6)
1. a kind of grid-connected converter exports phase-locked loop systems characterized by comprising
Clark conversion module, the three-phase voltage signal for exporting to grid-connected converter carry out Clark and convert to obtain α β coordinate
Two-phase voltage under system；
Be delayed cancellation module, eliminates for carrying out delay to the two-phase voltage under α β coordinate system to obtain the α β after eliminating delay and sit
Two-phase voltage under mark system；
Park conversion module, for being carried out according to initial output phase to the two-phase voltage under the α β coordinate system after eliminating delay
Park is converted to obtain d axis signal and q axis signal；
Pi regulator is adjusted for carrying out PI to q axis signal to obtain network voltage estimated value and frequency and adjust error；
Integration module, for carrying out Integral Processing to network voltage estimated value to obtain initial output phase；
Amplification module amplifies processing for adjusting error to frequency to obtain phase compensation amount；
Laminating module, for being overlapped processing to initial output phase and phase compensation amount to obtain final output phase；
The transmission function of the delay cancellation moduleWherein, n=2mAnd m is positive integer, s is
Complex frequency, e are natural constant, and j is imaginary unit, T=0.02 seconds；Or the transmission function of the delay cancellation moduleWherein, m is the positive integer greater than 1, and s is Complex frequency, and e is natural constant, j
For imaginary unit, T=0.02 seconds.
2. grid-connected converter according to claim 1 exports phase-locked loop systems, which is characterized in that the amplification module is put
Big coefficient
3. grid-connected converter according to claim 1 exports phase-locked loop systems, which is characterized in that the amplification module is put
Big coefficient
4. a kind of grid-connected converter output control method characterized by comprising
Using DC bus-bar voltage average value as controlled volume, trapper is added in DC voltage feedback channel；
Positive-negative sequence current decoupling controller is set under positive-negative sequence dual rotary coordinate system respectively, wherein the instruction of positive sequence watt current
It is determined by direct current outer ring, negative phase-sequence watt current instruction is zero, and positive sequence active component instruction is according to scheduling reactive voltage control system
The Reactive-power control target of generation obtains, negative phase-sequence referenced reactive current according toIt obtains,It is grid-connected
The negative phase-sequence q axis component of output current of converter,For network voltage negative phase-sequence d axis component,Electric current is exported for grid-connected converter
Positive sequence q axis component,For network voltage positive sequence d axis component, ω0For fundamental frequency, LgFor the grid-connected inductance of grid-connected converter；
It is adjusted by PI and carries out current follow-up control, and consider the current decoupled control under dq coordinate system；
The signal obtained after current decoupled control is folded with the component of voltage under positive-negative sequence dual rotary coordinate system respectively
Add, the phase of superimposed signal is that the described in any item grid-connected converters of claims 1 to 3 export in phase-locked loop systems most
Whole output phase；
Double coordinate transforms are carried out to superimposed signal to obtain modulated signal, and modulated signal is exported extremely by PWM transformation
The control terminal of the IGBT of grid-connected converter.
5. grid-connected converter output control method according to claim 4, which is characterized in that the center frequency of the trapper
Rate is twice of fundamental frequency.
6. grid-connected converter output control method according to claim 5, which is characterized in that the transmitting letter of the trapper
Number isWherein, ζ is damped coefficient.
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| CN201710464982.3A CN107257136B (en) | 2017-06-19 | 2017-06-19 | Grid-connected converter exports phase-locked loop systems and control method |
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| CN201710464982.3A CN107257136B (en) | 2017-06-19 | 2017-06-19 | Grid-connected converter exports phase-locked loop systems and control method |
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| CN108226588A (en) * | 2017-11-01 | 2018-06-29 | 中国矿业大学(北京) | It is a kind of to be suitable for single-phase and three-phase electrical power system Method of Software Phase Lock |
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| CN108828933B (en) * | 2018-07-03 | 2021-06-11 | 唐瑭 | Control method and system for improving output waveform quality of grid-connected converter |
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| CN110165706B (en) * | 2019-05-30 | 2022-11-25 | 辽宁工程技术大学 | Self-adaptive three-phase grid-connected converter phase-locked loop and phase-locked control method thereof |
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| CN112034242B (en) * | 2020-08-18 | 2022-08-02 | 安徽科技学院 | Method for eliminating DC bias voltage and single-phase-locked loop thereof |
| CN112600537B (en) * | 2020-12-10 | 2024-01-26 | 国网湖南省电力有限公司 | Improved adaptive trap and improved adaptive trap phase-locked loop |
| CN113346785B (en) * | 2021-04-30 | 2022-05-31 | 云南电网有限责任公司楚雄供电局 | Adaptive error compensation control system and method for inverter |
| CN113315401B (en) * | 2021-06-03 | 2022-03-29 | 昱能科技股份有限公司 | Micro inverter and grid-connected output control method and device thereof |
| CN113904373B (en) * | 2021-11-03 | 2024-04-09 | 重庆大学 | Stability enhancement control method for grid-connected converter under different output working conditions |
| CN114243793A (en) * | 2021-11-12 | 2022-03-25 | 国网重庆市电力公司电力科学研究院 | Novel phase-locked loop suitable for VSC inserts under weak receiving end alternating current network |
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