CN103414330A - Method for restraining grid-connected current spikes of single-phase grid-connected inverter - Google Patents
Method for restraining grid-connected current spikes of single-phase grid-connected inverter Download PDFInfo
- Publication number
- CN103414330A CN103414330A CN2013103662057A CN201310366205A CN103414330A CN 103414330 A CN103414330 A CN 103414330A CN 2013103662057 A CN2013103662057 A CN 2013103662057A CN 201310366205 A CN201310366205 A CN 201310366205A CN 103414330 A CN103414330 A CN 103414330A
- Authority
- CN
- China
- Prior art keywords
- grid
- current
- dmax
- duty ratio
- output
- 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
Images
Landscapes
- Inverter Devices (AREA)
Abstract
The invention relates to a method for restraining grid-connected current spikes of a single-phase grid-connected inverter. When the voltage of a grid suddenly rises, a bus voltage has no time to rise, if a grid-connected current is output in an inverted mode, a concave ditch will be formed because of the insufficient bus voltage, and accordingly a high current spike is formed on top of the concave ditch under the action of integrals. The method for restraining the grid-connected current spikes of the single-phase grid-connected inverter is characterized by comprising the following steps that (1) an output Vc of a current regulator is compared with a carrier wave Vtri to form a duty ratio D, the duty ratio D generally has a maximum value limit Dmax and is smaller than one; (2) amplitude limiting is conducted on the output of the regulator digitally controlled; (3) the duty ratio D is detected continuously, when the D reaches the Dmax, counting is started, and when the D reaches the Dmax by N times continuously, a bit flag equaling 1 is marked. The method for restraining the grid-connected current spikes of the single-phase grid-connected inverter can ensure that the waveform of an output current will not generate a spike because of sudden rising of the grid.
Description
Technical field
The present invention relates to a kind of in based on numerically controlled single-phase grid-connected inverter due to the jump inhibition method of the grid-connected current spike that causes of line voltage.
Background technology
In the single-phase two-stage grid-connected inverter of generally application, prime is the DC circuit part, and rear class is the inverter circuit part, and energy is reverse into to alternating current, and in being connected to the grid, centre is DC bus, referring to Fig. 1.Prime is responsible for following the tracks of the maximum power of photovoltaic battery panel, and energy is imported in DC bus, and rear class is reverse into the energy of bus and the electric current of electrical network with the frequency homophase, enters electrical network.When the line voltage effective value was basicly stable usually, the mean value of the voltage of DC bus was also fixed value, and its magnitude of voltage is controlled by the inverter circuit of rear class.But when line voltage raises suddenly, the voltage of bus has little time to raise, the grid-connected current of inversion output will form a pit not due to busbar voltage, and then under the effect of integration, and then form a higher current spike, referring to Fig. 2, current spike is easy to the components and parts of circuit are damaged.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of method that suppresses single-phase grid-connected inverter grid-connected current spike, the grid-connected current spike problem formed when line voltage jumps to solve single-phase grid-connected inverter.
For solving the problems of the technologies described above, the technical solution adopted in the present invention is: a kind of method that suppresses single-phase grid-connected inverter grid-connected current spike, and its special feature is: comprise the following steps:
(1) the output Vc of current regulator and carrier wave Vtri relatively form duty ratio D, and general duty ratio D has a maximum restriction Dmax, described duty ratio Dmax<1;
(2) in numerically controlled adjuster, adjuster is exported and done amplitude limit;
(3) detect duty ratio D always, after D reaches Dmax, start counting, after D N continuous time reaches Dmax, flag bit flag=1 of mark; When wherein N is greater than normal operation, reach the number of times of Dmax.
(4) after flag=1 being detected, judge whether current sampling data iL equates with the difference of current reference value iref, when error peak current 10% in, just think to equate, if equate locking is exactly the b point this moment;
(5) after locking b point, by the integration zero clearing of current regulator currPI.
In above-mentioned steps (3), N is 6.
Compared with prior art, beneficial effect of the present invention is: the present invention need not use the element of any hardware, do not need to increase exponent number and the type of controller, do not need complicated algorithm, namely can allow output current wave can not produce spike because of the unexpected rising of electrical network.
The accompanying drawing explanation
Below in conjunction with drawings and embodiments, describe the present invention in detail:
Fig. 1 is two-stage single-phase grid-connected inverter system block diagram in prior art;
Fig. 2 is that DC bus-bar voltage is lower than line voltage the time and the corresponding diagram of output current wave;
Fig. 3 is the control structure system block diagram of inverter circuit (DC/AC) part.
Embodiment
A kind of method that suppresses single-phase grid-connected inverter grid-connected current spike, Fig. 3 is the current controlled circuit figure of the rear class part of generally combining inverter, in Fig. 2, can see when line voltage jumps, the peak value part voltage of line voltage can be greater than the voltage of DC bus, again in conjunction with as can be known in Fig. 3, when Vgrid becomes large, VL voltage will reduce, inductive current iL will reduce, just there will be pit as shown in Figure 2, yet the given iref of electric current is a complete sine, as shown in iref indication lines in Fig. 2, at this moment the current error amount ie in Fig. 3 will increase, and current regulator PI will carry out error integration, until in Fig. 2 after the b point, line voltage is less than DC bus-bar voltage, due to PI before, adjust the integral action of machine this time, the duty ratio D of switch drive that will control inverter increases, cause the b point spike to occur with the waveform of after-current.A kind of method that suppresses single-phase grid-connected inverter grid-connected current spike, the method can accurately detect a point in Fig. 2 and occur to the current conditions of this section of b point, thereby, by the integration zero clearing of pi regulator, after b point, just not there will be like this current spike.
Specifically comprise the following steps:
(1) the output Vc of current regulator and carrier wave Vtri relatively form duty ratio D, and general duty ratio D has a maximum restriction Dmax (Dmax<1);
(2) in numerically controlled adjuster, can do amplitude limit to adjuster output, to avoid spillover, as shown in Figure 2, in Fig. 2 after a point, current regulator currentPI can reach rapidly amplitude limit value due to the increase of current error ie, thereby makes D be increased to Dmax;
(3) detect duty ratio D always, after D reaches Dmax, start counting, after D N continuous time reaches Dmax, flag bit flag=1 of mark, (flag=0 before); Wherein N is 6;
(4) after flag=1 being detected, judge whether current sampling data iL equates with the difference of reference value iref, when error peak current 10% in, just think to equate, if equate locking is exactly the b point this moment;
(5) after locking b point, by the integration zero clearing of current regulator currPI;
The discretization function of pi regulator is:
y(n) = y(n-1) + k1*e(n) -k2*e(n-1) （1）
The original shape of the current regulator currPI that above-mentioned steps is mentioned is also the represented mode of formula (1), wherein y (n) is the final output of currPI, y (n-1) is last currPI output, e (n) is this error input variable, be the ie in Fig. 3, e (n-1) is last error input variable, and k1 and k2 are the controller coefficient.After (4) bar of the concrete steps of detection method, by the integrator zero clearing, method of operation is exactly that the y (n-1) in formula (1), e (n-1) zero clearing are got final product.
Claims (2)
1. method that suppresses single-phase grid-connected inverter grid-connected current spike is characterized in that: comprise the following steps:
(1) the output Vc of current regulator and carrier wave Vtri relatively form duty ratio D, and general duty ratio D has a maximum restriction Dmax, described duty ratio Dmax<1;
(2) in numerically controlled adjuster, adjuster is exported and done amplitude limit;
(3) detect duty ratio D always, after D reaches Dmax, start counting, after D N continuous time reaches Dmax, flag bit flag=1 of mark; When wherein N is greater than normal operation, reach the number of times of Dmax;
(4) after flag=1 being detected, judge whether current sampling data iL equates with the difference of current reference value iref, when error peak current 10% in, just think to equate, if equate locking is exactly the b point this moment;
(5) after locking b point, by the integration zero clearing of current regulator currPI.
2. a kind of method that suppresses single-phase grid-connected inverter grid-connected current spike according to claim 1 is characterized in that: in described step (3), N is 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310366205.7A CN103414330B (en) | 2013-08-21 | 2013-08-21 | A kind of method suppressing single-phase grid-connected inverter grid-connected current spike |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310366205.7A CN103414330B (en) | 2013-08-21 | 2013-08-21 | A kind of method suppressing single-phase grid-connected inverter grid-connected current spike |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103414330A true CN103414330A (en) | 2013-11-27 |
| CN103414330B CN103414330B (en) | 2015-12-23 |
Family
ID=49607322
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310366205.7A Active CN103414330B (en) | 2013-08-21 | 2013-08-21 | A kind of method suppressing single-phase grid-connected inverter grid-connected current spike |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103414330B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107425546A (en) * | 2017-08-25 | 2017-12-01 | 上海蓝瑞电气有限公司 | It is accurate to adjust inverter busbar voltage so as to improve the method for grid connection efficiency |
| CN108173279A (en) * | 2016-12-08 | 2018-06-15 | 华能新能源股份有限公司辽宁分公司 | The soft grid-connection control device and control method of permanent magnet direct-drive wind turbine |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1165593A (en) * | 1995-09-27 | 1997-11-19 | 三菱电机株式会社 | Controller for PWM-controlled converter |
| US20060176037A1 (en) * | 2005-02-08 | 2006-08-10 | Flatness Randy G | Protection for switched step up/step down regulators |
-
2013
- 2013-08-21 CN CN201310366205.7A patent/CN103414330B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1165593A (en) * | 1995-09-27 | 1997-11-19 | 三菱电机株式会社 | Controller for PWM-controlled converter |
| US20060176037A1 (en) * | 2005-02-08 | 2006-08-10 | Flatness Randy G | Protection for switched step up/step down regulators |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108173279A (en) * | 2016-12-08 | 2018-06-15 | 华能新能源股份有限公司辽宁分公司 | The soft grid-connection control device and control method of permanent magnet direct-drive wind turbine |
| CN107425546A (en) * | 2017-08-25 | 2017-12-01 | 上海蓝瑞电气有限公司 | It is accurate to adjust inverter busbar voltage so as to improve the method for grid connection efficiency |
| CN107425546B (en) * | 2017-08-25 | 2020-09-29 | 上海蓝瑞电气有限公司 | Method for accurately adjusting bus voltage of inverter so as to improve grid-connected efficiency |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103414330B (en) | 2015-12-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101582592B (en) | Transformer-less photovoltaic merging and inverting device and control method thereof | |
| EP3796507A1 (en) | Direct-current bus voltage reference value adjustment method and apparatus, and photovoltaic grid-connected inverter | |
| CN102918756B (en) | Leakage current control method in inverter system | |
| EP2790312A2 (en) | Power decoupling controller and method for power conversion system | |
| CN103441686B (en) | Control system and method for braking module of DC busbars of wind-power current transformer | |
| CN103311957B (en) | A kind of net side converter control method and system | |
| Tiang et al. | Modeling and simulation of deadbeat-based PI controller in a single-phase H-bridge inverter for stand-alone applications | |
| CN106950512B (en) | Energy storage converter grid-connected and grid-disconnected characteristic integrated detection system and method | |
| Emhemed et al. | The effectiveness of using IEC61660 for characterising short-circuit currents of future low voltage DC distribution networks | |
| CN105406748A (en) | Control method for suppressing modularized multi-level current transformer output current harmonic wave | |
| CN104578886A (en) | Pulse width modulation method for three-level photovoltaic inverter and modulator | |
| CN103904670A (en) | Bidirectional transducer of flywheel energy storage system and control method of bidirectional transducer | |
| CN103078344A (en) | Method for improving double-fed converter low voltage ride through performance | |
| Chen et al. | Harmonic components based protection strategy for inverter-interfaced AC microgrid | |
| CN109196766B (en) | Bidirectional insulation type DC/DC converter and smart power grid | |
| CN101257215A (en) | Three-phase four-wire photovoltaic parallel network generating system | |
| CN104979846A (en) | Method, equipment and system for controlling low voltage ride through of multilevel inverter | |
| CN103515981B (en) | Grid-connected photovoltaic power generation system and self-action phase shift island phenomenon detection method thereof | |
| Parikh et al. | Design and implementation of solar pumping system with induction motor and submersible pump | |
| CN103414330B (en) | A kind of method suppressing single-phase grid-connected inverter grid-connected current spike | |
| CN103346570A (en) | Solar photovoltaic power generation dynamic voltage compensator with energy storage function | |
| Bottu et al. | A Power electronic conditioner using ultracapacitors to improve wind turbine power quality | |
| CN103326601B (en) | Current-impact-free grid-connecting control method of PWM rectifier | |
| Lakshminarayanan et al. | Current mode control of single phase grid tie inverter with anti-islanding | |
| CN104052321A (en) | Hybrid control method and system for microinverter zero crossing point current distortion suppression |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 710021 export processing zone, No. twelve, 1 road, Fengcheng, Shaanxi, Xi'an Patentee after: Longteng Semiconductor Co.,Ltd. Address before: 710021 export processing zone, No. twelve, 1 road, Fengcheng, Shaanxi, Xi'an Patentee before: LONTEN SEMICONDUCTOR Co.,Ltd. Address after: 710021 export processing zone, No. twelve, 1 road, Fengcheng, Shaanxi, Xi'an Patentee after: LONTEN SEMICONDUCTOR Co.,Ltd. Address before: 710021 export processing zone, No. twelve, 1 road, Fengcheng, Shaanxi, Xi'an Patentee before: XI'AN LONTEN RENEWABLE ENERGY TECHNOLOGY Inc. |
|
| CP01 | Change in the name or title of a patent holder |