CN110518624A - A kind of low voltage traversing control method based on photovoltaic combining inverter - Google Patents
A kind of low voltage traversing control method based on photovoltaic combining inverter Download PDFInfo
- Publication number
- CN110518624A CN110518624A CN201810498130.0A CN201810498130A CN110518624A CN 110518624 A CN110518624 A CN 110518624A CN 201810498130 A CN201810498130 A CN 201810498130A CN 110518624 A CN110518624 A CN 110518624A
- Authority
- CN
- China
- Prior art keywords
- power
- voltage
- gird
- grid
- inverter
- 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.)
- Pending
Links
Classifications
-
- 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
- H02J3/12—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load
- H02J3/16—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load by adjustment of reactive power
-
- 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
- Y02E40/30—Reactive power compensation
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention discloses a kind of low voltage traversing control methods based on photovoltaic combining inverter.Large-scale and medium-sized photo-voltaic power supply should all have the ability for bearing certain voltage exception, give power grid bring baneful influence to avoid the off-grid suddenly of photo-voltaic power supply.When grid collapses or the biggish disturbance of appearance, excision photo-voltaic power supply often brings impact very serious to power grid, in order to effectively avoid the impact on power grid from influencing, the reactive power that the present invention injects acts on emotional resistance, generate corresponding voltage, and then the effect of lifting is formed to grid entry point voltage, network voltage is supported, power system security and stability are improved.
Description
Technical field
The invention belongs to electric power system and its automation field, in particular to a kind of low electricity based on photovoltaic combining inverter
Press to wear more controller design.
Background technique
In recent years, shared specific gravity is increasing in the power system for photovoltaic, which results in when grid collapses or
When biggish disturbance occurs in person, excision photo-voltaic power supply often brings impact very serious to power grid.Therefore from power grid security
From the perspective of operation, large-scale and medium-sized photo-voltaic power supply should all have the ability for bearing certain voltage exception, to avoid light
The off-grid suddenly of volt power supply gives power grid bring baneful influence.It is similar with the low voltage crossing technology of wind-power electricity generation, when power grid event
Barrier or by large disturbances when, lead to photo-voltaic power supply grid entry point Voltage Drop, in defined Voltage Drop range and between the duration
Every interior, photo-voltaic power supply is not capable of the stable operation of off-grid.Quantitative reactive power is conveyed to power grid simultaneously, for supporting power grid electric
The recovery of pressure, enables power grid to restore stable operation as soon as possible.
Current developed countries many in the world are made that corresponding specification for photo-voltaic power supply low voltage ride-through capability, due to
The system parameters such as frequency, the voltage class of each national grid have differences, so the relevant criterion formulated all is not quite similar.
For the development of China's photovoltaic technology, some countries in Europe have been walked in photovoltaic technology field in our forefront, light
Generation technology also comparative maturity is lied prostrate, China can be conducive in technical field of photovoltaic power generation with reference to the mature experience of these countries
Development.
The superiority of photovoltaic power generation can be preferably played by the research of photovoltaic low voltage crossing technology.So for low
The research that continues deeper into of voltage ride-through technology is essential, so that when Voltage Drop failure occurs in power grid, photovoltaic electric
Source is not capable of the stable operation of off-grid and injects reactive power to power grid, contributes for power system restoration stable operation.
When power grid falls failure, inverter current be increased dramatically, may be because of the excessive damage power switch of electric current
Pipe, causes low voltage crossing to fail.However traditional photovoltaic low voltage crossing technology focuses on power and current quality more, to mistake
Current problems research is less.
Summary of the invention
The purpose of the present invention is to provide one kind.
In order to solve the above-mentioned technical problem, the present invention proposes a kind of low voltage crossing control based on photovoltaic combining inverter
Method, comprising the following steps:
Step 1: establishing gird-connected inverter in network voltage asymmetry according to the topological structure of synchronization inverter main circuit
In the case where power module, then the active power and the mathematical model of reactive power of gird-connected inverter output are sat by d-q
Mark system is transformed to alpha-beta coordinate system, obtains the active power and reactive power mathematical model under alpha-beta coordinate system;
Step 2: passing through the calculating of positive-negative sequence voltage magnitude, dip type is judged, after the judgement of dip type,
Calculate the given value Q of positive-negative sequence reactive power*, then calculating being averaged for gird-connected inverter output by DC voltage outer ring has
Function power P*;
Step 3: according to the given value Q of active power and reactive power mathematical model and reactive power*Averagely have
Function power P*, the control target inhibited based on net side negative-sequence current is established, is calculated in the electric current in the case of grid voltage sags
The positive-negative sequence current instruction references value of ring;
Step 4: establishing the transmission function of quasi- ratio resonant controller, quasi- ratio resonant controller parameter is then completed
Selection, so that the design of quasi- ratio resonant controller is completed, finally by quasi- ratio resonant controller to positive and negative under alpha-beta coordinate system
The DAZ gene of sequence current reference value completes the control to low voltage crossing.
Compared with prior art, the present invention its remarkable advantage is: (1) this is from the topological structure of gird-connected inverter,
Positive-negative sequence vector math model of the gird-connected inverter under d-q coordinate system is constructed, there is specific physical significance, can be managed
The controller thought;(2) low voltage traversing control method proposed by the present invention based on photovoltaic combining inverter, can neatly control
Grid-connected current, is effectively limited in rated range by power processed, while utmostly compensating network voltage, to support power grid extensive
Multiple, entire control strategy improves the reliability passed through when network voltage failure;(3) control method of the invention reduces very much
Unnecessary coordinate transform and positive-negative sequence separation calculate, so that Control system architecture is more simplified, strengthen the dynamic of control system
State response speed has very high engineering practical value.
Detailed description of the invention
Fig. 1 is the flow chart of the quasi- proportional resonant control method the present invention is based on two-phase stationary coordinate system.
Fig. 2 is the three-phase photovoltaic grid-connected inverting device topology diagram the present invention is based on LC filter.
Fig. 3 is the present invention in different kpUnder the conditions of GQPR(s) Bode figure.
Fig. 4 is that the present invention is based on Second Order Generalized Integrator (SOGI) magnitude extraction structure charts.
Fig. 5 is that the present invention is based on the low voltage traversing control method block diagrams of quasi- ratio resonant controller.
Specific embodiment
In order to solve the above-mentioned technical problem, the present invention proposes a kind of low voltage crossing control based on photovoltaic combining inverter
Method, comprising the following steps:
Step 1: establishing gird-connected inverter in network voltage asymmetry according to the topological structure of synchronization inverter main circuit
In the case where power module, by gird-connected inverter output active power and reactive power mathematical model by d-q coordinate system
It is transformed to alpha-beta coordinate system, obtains the active power and reactive power mathematical model under alpha-beta coordinate system;
Step 2: judging dip type according to the positive-negative sequence voltage magnitude of calculating, according to dip type, positive-negative sequence is calculated
The given value Q of reactive power*, the average active power P of gird-connected inverter output is then calculated by DC voltage outer ring*;
Step 3: according to the given value Q of active power and reactive power mathematical model and reactive power*Averagely have
Function power P*, the control target inhibited based on net side negative-sequence current is established, is calculated in the electric current in the case of grid voltage sags
The positive-negative sequence current instruction references value of ring;
Step 4: establishing the transmission function of quasi- ratio resonant controller, the selection of quasi- ratio resonant controller parameter is completed,
To complete the design of quasi- ratio resonant controller, positive-negative sequence current under alpha-beta coordinate system is joined by quasi- ratio resonant controller
The DAZ gene of value is examined, the control to low voltage crossing is completed.
In further embodiment, in step 1, gird-connected inverter is established in the asymmetric situation of network voltage in conjunction with Fig. 1
Under power module specifically:
In formula, P0For the active power DC quantity of gird-connected inverter output, Q0Reactive power for gird-connected inverter output is straight
Flow, Psin2, Pcos2Respectively active power quadratic sine, cosine component coefficient;Qsin2, Qcos2Respectively reactive power is secondary
Sinusoidal, cosine component coefficient.
The establishment process of power module of the gird-connected inverter in the asymmetric situation of network voltage are as follows:
When unbalanced fault occurs for power grid, the voltage and current of positive and negative order components can be generated, in order to analyze network voltage
The operation characteristic of gird-connected inverter under non-equilibrium state, the present invention initially set up the parallel network reverse under unbalanced source voltage state
Device mathematical model.
The complex vector expression formula of three-phase power grid voltage under the static α β coordinate system of two-phase are as follows:
Wherein, ea~ecRepresent power grid three-phase voltage, E in formulaαβFor three-phase power grid voltage under the static α β coordinate system of two-phase, Respectively EαβPositive and negative order components.Formula (1) can be rewritten into the complex vector under two-phase synchronous rotating frame (d-q)
Expression formula:
E in formulaαβFor three-phase power grid voltage under d-q coordinate system,Respectively E under two-phase rotating coordinate systemdq
Positive and negative order components, wherein vector Edq=(ed, eq)T, and wherein
For the topological structure of synchronization inverter main circuit, gird-connected inverter complex vector under the static α β coordinate system of two-phase is obtained
Model equation are as follows:
Uαβ=Eαβ+R·Iαβ+L·pIαβ (3)
In formula: UαβSide voltage phasor is exchanged for gird-connected inverter in α β coordinate system;IαβFor parallel network reverse in α β coordinate system
Device ac-side current complex vector, L are the filter inductance of inverter, and R represents the internal resistance of inverter filtering inductance, and p is differential operator.
When power grid is in non-equilibrium state, under d-q coordinate system, UαβAnd IαβAll contain positive and negative order components, expression formula
Are as follows:
In formula, vector Udq=(ud, uq)T, Idq=(id, iq)T, ω is synchronous rotary angular frequency.
By formula (1)~(5) it can be concluded that positive-negative sequence vector math model of the gird-connected inverter under d-q coordinate system are as follows:
When power grid is in non-equilibrium state, the active power and reactive power of gird-connected inverter output are respectively as follows:
Formula (4) and (5) are substituted into formula (7) respectively, gird-connected inverter can be obtained in the asymmetric situation of network voltage
Under power module:
In formula, P0For the active power DC quantity of gird-connected inverter output, Q0Reactive power for gird-connected inverter output is straight
Flow, Psin2, Pcos2Respectively active power quadratic sine, cosine component coefficient;Qsin2, Qcos2Respectively reactive power is secondary
Sinusoidal, cosine component coefficient.
Wherein:
In further embodiment, according to the mathematical model of photovoltaic combining inverter under unbalanced fault, by formula (9) and formula
It (10) is alpha-beta coordinate system from d-q coordinate system transformation, so that arrangement obtains active under alpha-beta coordinate system and reactive power equation such as
Shown in formula (11):
In further embodiment, in step 2, in conjunction with Fig. 4, when Second Order Generalized Integrator (SOGI) centre frequency with
When the frequency of input signal is consistent, output two orthogonal signalling and input signal it is in the same size, then pass through crest meter
It calculates module and seeks voltage magnitude, this method calculation amount is small, and dynamic property is good, and SOGI is by bandpass filter and low-pass filtering
Device composition, can also filter signal.
Requirement of photovoltaic DC-to-AC converter when grid-connected, for network voltage are as follows:
When voltage magnitude is more than mains voltage range, according to the number of phases of Voltage Drop, voltage sag type is determined,
Concrete type are as follows:
(1) single-phase to fall reference voltage given value
(2) two-phase falls reference voltage given value
(3) drop-off voltage reference value is balanced
In formula
The given value of positive-negative sequence reactive power are as follows:
The average active power P of gird-connected inverter output*Still via being provided after the PI controller operation of outer voltage, such as
Shown in formula (14):
In formula, kvpAnd kv1The respectively proportional gain of the PI controller of outer voltage and integral gain, UMPPTFor maximum work
Output voltage under rate point-tracking method, UPVFor photovoltaic output voltage.
In further embodiment, the positive and negative order components and inverter of network voltage and grid-connected current are analyzed in step 3
Active power of output P0Relationship between value calculates the reference value of positive and negative sequence current component.Then it according to symmetrical component method, asks
The instruction value of α, β shaft current component out.
We are known when unbalanced source voltage, active power and reactive power include two frequencys multiplication sinusoidal fluctuation and
The cosine of two frequencys multiplication fluctuates, and then, the control target (inhibiting the control target based on net side negative-sequence current) of gird-connected inverter can
To be divided into three classes:
1, two double-frequency fluctuations for eliminating active power of output, even Psin2=Pcos2=0;
2, two double-frequency fluctuations for eliminating output reactive power, even Qsin2=Qcos2=0;
3, it eliminates negative phase-sequence and exports electric current, keep current-symmetrical sinusoidal.
Since three kinds of control targets not can be implemented simultaneously, and the fluctuation of active power and reactive power can not disappear simultaneously
It removes, therefore for control target 3, to inhibit in the case where grid voltage sags, to calculate in electric current based on net side negative-sequence current
The positive-negative sequence current instruction references value of ring are as follows:
P*The active power of power grid, Q are sent to for inverter*The reactive power of power grid is sent to for inverter, to reference electricity
Stream instruction integration, finds out the instruction value of α, β shaft current component:
In further embodiment, since the resonance of two times of power frequencies can be generated when asymmetrical voltage failure in step 4, make
Tracking error will be generated with ratio resonant controller.Therefore, using the quasi- ratio changed based on ratio resonant controller
Resonant controller can effectively avoid this case, and quasi- ratio resonant controller can effectively eliminate two harmonic institute bands
The influence come.The transmission function of quasi- ratio resonant controller are as follows:
In formula: ωcFor bandwidth angular frequency, ω0For resonance angular frequency, kpFor proportionality coefficient, krFor resonance gain coefficient.
From formula (20) it is found that gain of the quasi- ratio resonant controller at angular frequency has become 201g (k from infinityp+
kr), it increased with Time Bandwidth, although gain of the quasi- ratio resonant controller at angular frequency is no longer infinity,
Reasonable selection parameter, which is ensured that, improves bandwidth while realizing higher gain.
In certain embodiments, the parameter designing of quasi- ratio resonant controller is as follows:
(1)ωc
National grid regulation, the deviation that electric system normally allows is ± 0.2Hz, when capacity is smaller, this range
± 0.5Hz can be decontroled, it is contemplated that frequency departure is set as 2.5Hz, then has ω by measurement errorc=2.5 π.
(2)ω0
The resonance frequency f of QPR adjuster0=100Hz, then resonance angular frequency ω0=2 π f0=628 (rad/s).
(3)kr
Work as krWhen smaller (such as≤100), with krIncrease, GQPR(s) it is gradually reduced in the amplitude gain of 100Hz, electricity
Harmonic inhibition capability enhancing is pressed, and the cutoff frequency of system, phase margin and gain margin are all basically unchanged, and will not influence system
Stability.Work as krWhen larger, although GQPR(s) become smaller in the amplitude of 100Hz, but the phase margin of system also sharply subtracts
It is small, even less than 0, system is by loss of stability at this time.
(4)kp
By GQPR(s) in kpIt takes in Bode diagram when different parameters i.e. Fig. 3 as can be seen that working as kpWhen value is 1, QPR control
Amplitude gain of the device at disresonance frequence is essentially 0, since target is exactly to inhibit to the component of two frequencys multiplication, to other frequencies
Amplitude-frequency characteristic needs at rate remain unchanged, so take kp=1.
Fig. 5 is finally combined, by quasi- ratio resonant controller to the floating of positive-negative sequence current reference value under alpha-beta coordinate system
Tracking, completes the control of low voltage crossing.It not only can effectively inhibit the negative sequence component of current on line side, and compared to
For control method under d-q coordinate system, reduces many unnecessary coordinate transforms and positive-negative sequence separation calculates, so that control
System structure is more simplified, and the dynamic responding speed of control system is strengthened, and ensure that the low voltage ride-through capability of inverter.
Low voltage traversing control method based on photovoltaic combining inverter proposed by the invention solves traditional low electricity
The problem of pressure traversing control method is easy to cause inverter overcurrent during failure and cannot effectively support grid-connected voltage, improves
The reliability passed through when network voltage failure.Power grid occur it is single-phase fall failure, two-phase falls failure, three-phase symmetrical fall therefore
When barrier, inverter current be increased dramatically, and low voltage crossing may be caused to fail because of the excessive damage power switch tube of electric current.It answers
Low voltage traversing control method is proposed with the present invention, DC voltage can be inhibited excessively high during electric network fault, is injected idle
Power plays a supporting role to grid entry point voltage, and then is conducive to low voltage crossing during failure, improves network voltage failure
When the reliability passed through.
Claims (7)
1. a kind of low voltage traversing control method based on photovoltaic combining inverter, which comprises the following steps:
Step 1: establishing gird-connected inverter in the asymmetric feelings of network voltage according to the topological structure of synchronization inverter main circuit
Power module under condition, by the mathematical model of the active power of gird-connected inverter output and reactive power by d-q coordinate system transformation
For alpha-beta coordinate system, the active power and reactive power mathematical model under alpha-beta coordinate system are obtained;
Step 2: judging dip type according to the positive-negative sequence voltage magnitude of calculating, according to dip type, it is idle to calculate positive-negative sequence
The given value Q of power*, the average active power P of gird-connected inverter output is then calculated by DC voltage outer ring*;
Step 3: according to the given value Q of active power and reactive power mathematical model and reactive power*And average active power
P*, the control target inhibited based on net side negative-sequence current is established, is calculating current inner loop in the case of grid voltage sags just
Negative current instructions reference value;
Step 4: establishing the transmission function of quasi- ratio resonant controller, the selection of quasi- ratio resonant controller parameter is completed, thus
The design for completing quasi- ratio resonant controller, by quasi- ratio resonant controller to positive-negative sequence current reference value under alpha-beta coordinate system
DAZ gene, complete control to low voltage crossing.
2. the low voltage traversing control method according to claim 1 based on photovoltaic combining inverter, which is characterized in that
Power module of the gird-connected inverter established in step 1 in the asymmetric situation of network voltage specifically:
In formula, P0For the active power DC quantity of gird-connected inverter output, Q0For the reactive power direct current of gird-connected inverter output
Amount, Psin2, Pcos2Respectively active power quadratic sine, cosine component coefficient;Qsin2, Qcos2Respectively reactive power is secondary just
String, cosine component coefficient.
3. the low voltage traversing control method according to claim 1 based on photovoltaic combining inverter, which is characterized in that
Active power and reactive power mathematical model under alpha-beta coordinate system obtained in step 1 are as follows:
In formula, P0For the active power DC quantity of gird-connected inverter output, Q0For the reactive power direct current of gird-connected inverter output
Amount, Psin2, Pcos2Respectively active power quadratic sine, cosine component coefficient;Qsin2, Qcos2Respectively reactive power is secondary just
String, cosine component coefficient, eα, eβRepresent three-phase power grid voltage under the static α β coordinate system of two-phase, iα, iβThe static α β of two-phase is represented to sit
Mark is lower three phase network electric current.
4. the low voltage traversing control method according to claim 1 based on photovoltaic combining inverter, which is characterized in that
The calculation formula of the given value of positive-negative sequence reactive power in step 2 are as follows:
5. the low voltage traversing control method according to claim 1 based on photovoltaic combining inverter, which is characterized in that
The average active power P that gird-connected inverter exports in step 2*Calculation formula are as follows:
In formula, kvpAnd kv1The respectively proportional gain of the PI controller of outer voltage and integral gain, UMPPTFor maximum power point
Output voltage under tracking, UPVFor photovoltaic output voltage.
6. the low voltage traversing control method according to claim 1 based on photovoltaic combining inverter, which is characterized in that
The positive-negative sequence current instruction references value of current inner loop in step 3 in the case of calculated grid voltage sags are as follows:
P*The active power of power grid, Q are sent to for inverter*The reactive power of power grid is sent to for inverter.
7. the low voltage traversing control method according to claim 1 based on photovoltaic combining inverter, which is characterized in that
The transmission function for the quasi- ratio resonant controller that step 4 kind is established specifically:
ωcFor bandwidth angular frequency, ω0For resonance angular frequency, kpFor proportionality coefficient, krFor resonance gain coefficient.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201810498130.0A CN110518624A (en) | 2018-05-21 | 2018-05-21 | A kind of low voltage traversing control method based on photovoltaic combining inverter |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201810498130.0A CN110518624A (en) | 2018-05-21 | 2018-05-21 | A kind of low voltage traversing control method based on photovoltaic combining inverter |
Publications (1)
Publication Number | Publication Date |
---|---|
CN110518624A true CN110518624A (en) | 2019-11-29 |
Family
ID=68622253
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201810498130.0A Pending CN110518624A (en) | 2018-05-21 | 2018-05-21 | A kind of low voltage traversing control method based on photovoltaic combining inverter |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN110518624A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112531774A (en) * | 2020-12-01 | 2021-03-19 | 辽宁东科电力有限公司 | Low-voltage ride-through operation control method of inverter type distributed power supply |
CN113098068A (en) * | 2021-05-13 | 2021-07-09 | 中国矿业大学(北京) | Photovoltaic grid-connected inverter impedance remodeling strategy matched with sequence component phase selection element |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102904458A (en) * | 2012-11-08 | 2013-01-30 | 南车株洲电力机车研究所有限公司 | Voltage sag generation device and control method and device for inverter |
CN103887820A (en) * | 2014-03-31 | 2014-06-25 | 上海电气集团股份有限公司 | Low-voltage ride-through method of high-power photovoltaic inverter |
CN104319805A (en) * | 2014-09-15 | 2015-01-28 | 浙江理工大学 | Control method for photovoltaic grid-connected inverter system |
-
2018
- 2018-05-21 CN CN201810498130.0A patent/CN110518624A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102904458A (en) * | 2012-11-08 | 2013-01-30 | 南车株洲电力机车研究所有限公司 | Voltage sag generation device and control method and device for inverter |
CN103887820A (en) * | 2014-03-31 | 2014-06-25 | 上海电气集团股份有限公司 | Low-voltage ride-through method of high-power photovoltaic inverter |
CN104319805A (en) * | 2014-09-15 | 2015-01-28 | 浙江理工大学 | Control method for photovoltaic grid-connected inverter system |
Non-Patent Citations (2)
Title |
---|
张磊: "光伏并网逆变器低电压穿越控制策略研究", 《电力电子技术》 * |
杨振兴: "三相光伏并网逆变器低电压穿越技术研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112531774A (en) * | 2020-12-01 | 2021-03-19 | 辽宁东科电力有限公司 | Low-voltage ride-through operation control method of inverter type distributed power supply |
CN113098068A (en) * | 2021-05-13 | 2021-07-09 | 中国矿业大学(北京) | Photovoltaic grid-connected inverter impedance remodeling strategy matched with sequence component phase selection element |
CN113098068B (en) * | 2021-05-13 | 2023-07-11 | 中国矿业大学(北京) | Photovoltaic grid-connected inverter impedance remodeling strategy matched with sequence component phase selection element |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
He et al. | Transient stability analysis and enhancement of renewable energy conversion system during LVRT | |
CN106532736B (en) | Based on the SVG negative phase-sequence zero sequence current compensation method for improving instantaneous symmetrical components | |
CN102751741B (en) | Low-voltage ride through (LVRT) control system of photovoltaic inverter and method thereof | |
CN104218590B (en) | Unbalance voltage compensating control method based on virtual synchronous machine | |
CN103078316B (en) | Network voltage disturbance generating device and control method thereof | |
CN102305886B (en) | Fundamental voltage synchronous signal detection method during harmonic distortion and unbalance of network voltage | |
CN110739678B (en) | Control method for series virtual impedance of grid-connected converter | |
CN107611991B (en) | Parameter design method of LC coupling type SVG under unbalanced power grid and control method and system thereof | |
CN108718094A (en) | A method of it improving large-sized photovoltaic system low-voltage and passes through performance | |
WO2021253368A1 (en) | Coordinated control system and method of wind turbine and statcom for suppressing unbalanced voltage in dispersed wind farm | |
CN106026140B (en) | Control device and method for three-phase unbalance and reactive compensation | |
CN106602916B (en) | A kind of mixing level three-phase four-bridge arm converter device and control method | |
CN109494755A (en) | A kind of virtual synchronous generator no-voltage passes through control system and control method | |
CN107947787A (en) | A kind of system self-adaption phase-locked loop method applied to high-power three-level back-to-back PWM converter | |
CN108879775A (en) | A kind of unbalanced power supply photovoltaic DC-to-AC converter control method for coordinating considering current limit | |
CN104950202A (en) | Island detection method and system based on reactive power-frequency positive feedback | |
CN105116195A (en) | Voltage drop detection method suitable for power grid voltage large harmonic content | |
CN105071390B (en) | Control method of H-bridge three-level active power filter and system | |
CN106300386B (en) | Frequency closed-loop control method for dynamically inhibiting subsynchronous oscillation of power grid based on SVG | |
CN110266008A (en) | Based on the improved more level active power filters of neutral-point-clamped type | |
CN109842150A (en) | Control method based on virtual synchronous machine low voltage crossing | |
Chawda et al. | Fuzzy logic based control algorithm for dstatcom connected to weak ac grid | |
CN110518624A (en) | A kind of low voltage traversing control method based on photovoltaic combining inverter | |
Suppioni et al. | Coordinated control for the series grid side converter-based DFIG at subsynchronous operation | |
CN104734537A (en) | Control method for wind power current converter based on positive-and-negative sequence current inner-loop control |
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 | ||
RJ01 | Rejection of invention patent application after publication |
Application publication date: 20191129 |
|
RJ01 | Rejection of invention patent application after publication |