CN113872207A - Low-carrier mixed harmonic elimination method based on active front-end converter of new energy microgrid system - Google Patents
Low-carrier mixed harmonic elimination method based on active front-end converter of new energy microgrid system Download PDFInfo
- Publication number
- CN113872207A CN113872207A CN202111101973.0A CN202111101973A CN113872207A CN 113872207 A CN113872207 A CN 113872207A CN 202111101973 A CN202111101973 A CN 202111101973A CN 113872207 A CN113872207 A CN 113872207A
- Authority
- CN
- China
- Prior art keywords
- low
- modulation ratio
- thd5
- amplitude modulation
- ratio
- 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
- 238000000034 method Methods 0.000 title claims abstract description 22
- 230000008030 elimination Effects 0.000 title claims abstract description 11
- 238000003379 elimination reaction Methods 0.000 title claims abstract description 11
- 238000013461 design Methods 0.000 abstract description 6
- 230000002035 prolonged effect Effects 0.000 abstract description 4
- 230000001629 suppression Effects 0.000 abstract description 2
- 238000011161 development Methods 0.000 description 5
- 230000003595 spectral effect Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 238000010248 power generation Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
Images
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
- H02J3/01—Arrangements for reducing harmonics or ripples
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/12—Arrangements for reducing harmonics from ac input or output
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
-
- 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
- Y02E40/40—Arrangements for reducing harmonics
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
Abstract
The invention relates to a low carrier mixed harmonic elimination method based on an active front-end converter of a new energy microgrid system, wherein a triple harmonic value is eliminated through a three-phase AFE converter, 17-frequency-doubled and 19-frequency-doubled high-frequency-doubled harmonics are eliminated by a low-pass filter, 5th, 7th, 11th and 13th low-order harmonic values are remained, THD operation realizes different amplitude ratios after passing through the low-pass filter, THD5, 7 and THD5, 7, 11 and 13 are compared, amplitude modulation ratio areas are obtained at 9 and 11 times of frequency modulation ratios according to the suppression of THD5, 7, 11 and 13 harmonics, the 9-frequency-doubled modulation ratio is used in the low amplitude modulation ratio area, and the 11-frequency-doubled modulation ratio is used in the high amplitude modulation ratio area; a mixing method of 9 times and 11 times of lower carrier ratio is applied by combining the SPWM method and the SVPWM method, the low harmonic wave band of the SPWM and the low harmonic wave band of the SVPWM are found in theoretical design for switching control, and a low carrier ratio PWM scheme is applied, so that the service life of an inverter converter is prolonged, the power consumption is reduced, and the greening of power inverter equipment is realized.
Description
Technical Field
The invention relates to the technical field of photovoltaic power generation, in particular to a low-carrier mixed harmonic elimination method based on an active front-end converter of a new energy microgrid system.
Background
With the rapid development of new energy, wind power generation and the expanded application of new photovoltaic power generation energy, the active front-end converter is taken as the most important component in the existing new energy utilization system, so that not only can energy be fed back to a power grid to achieve the purpose of energy saving, but also higher harmonics can be eliminated, the power factor is improved, the influence of the power grid is avoided, and the dynamic characteristic is excellent;
however, as the requirement of the conversion efficiency of the three-phase active front-end AFE converter is continuously improved, the energy consumption loss of the AFE converter is regarded as important, a low-carrier-ratio Pulse Width Modulation (PWM) scheme is proposed to reduce the switching loss of the AFE converter, and a lower switching frequency can also improve the service life of the device components, however, the problem of a large increase of harmonics due to the low-carrier-ratio scheme becomes more prominent.
The existing new energy microgrid equipment and electric vehicle inverter equipment mostly adopt a high-frequency carrier scheme, and an inverter converter is high in switching frequency, high in energy consumption and low in service life.
Disclosure of Invention
The invention aims to provide a low-carrier mixed harmonic elimination method based on an active front-end converter of a new energy microgrid system, and solves the technical problems that most inverter devices of the existing new energy microgrid devices and electric vehicles adopt a high-frequency carrier scheme, the inverter converters are high in switching frequency, high in energy consumption and low in service life, the low-carrier ratio PWM scheme is applied, the service life of the inverter converters is prolonged, the power consumption is reduced, and the greenization of electric inverter devices is realized.
In order to achieve the purpose, the invention adopts the following technical scheme:
a low-carrier mixed harmonic elimination method based on an active front-end converter of a new energy microgrid system comprises the following specific operation steps:
the method comprises the following steps: eliminating triple harmonic values through a three-phase AFE converter, and eliminating 17 frequency-doubled and 19 frequency-doubled high-frequency harmonic by a low-pass filter to obtain 5th, 7th, 11th and 13th low-order harmonic values;
step two: THD operation achieves different amplitude ratios after passing through a low pass filter, where THD5, 7 and THD5, 7, 11, 13 are compared;
step three: according to THD5, 7, 11, 13 harmonics are suppressed to obtain an amplitude modulation ratio region at 9 and 11 times of frequency modulation ratio by SVPWM scheme, the 9 times frequency modulation ratio is used in a low amplitude modulation ratio region, and the 11 times frequency modulation ratio is used in a high amplitude modulation ratio region.
Preferably, the THD5, 7 harmonics are suppressed by the SVPWM scheme at an 11-fold frequency modulation ratio in the amplitude modulation ratio region of 0.49< ma <1.0, the THD5, 7 is 0.35% by the SVPWM operation at the amplitude modulation ratio, ma ═ 0.8.
Preferably, the THD5, 7, 11, 13 harmonics are suppressed by SVPWM at 11 times frequency modulation ratio in the amplitude modulation ratio region to be 0.57< ma <1.0, the THD5, 7 is 0.35% by SVPWM scheme at amplitude modulation ratio, ma ═ 0.8.
Preferably, the THD5, 7, 11, 13 harmonics are suppressed to obtain an amplitude modulation ratio region at 11 times frequency modulation ratio by the SVPWM scheme, the amplitude modulation ratio region is 0.57< ma <1.0, when the amplitude ratio of operation is ma ═ 0.9, the THD5, 7, 11, 13 is 3.54%, when the 11 times frequency modulation ratio is controlled at high amplitude modulation ratio 0.57< ma <1.0, and at the same time the SPWM scheme is controlled at 9 times frequency modulation ratio at low amplitude modulation ratio 0.0< ma <0.57, the THD5, 7, 11, 13 is less than 30%;
when the SVPWM scheme with low carrier ratio is passed through the low pass filter at high amplitude modulation ratio ma of 0.8, THD5, 7 is reduced from 0.35% to 0.2%, and THD5, 7, 11, 13 is reduced from 7.3% to 1.3%;
when the low carrier ratio SPWM scheme passes through a low pass filter at a low amplitude modulation ratio ma of 0.4, THD5, 7 is reduced from 15.1% to 6.6% and THD5, 7, 11, 13 is reduced from 21.5% to 7.3%.
The invention has the beneficial effects that: a mixing method of 9 times and 11 times of lower carrier ratio is applied by combining the SPWM method and the SVPWM method, the low harmonic wave band of the SPWM and the low harmonic wave band of the SVPWM are found in the theoretical design, and switching control is carried out; and then, a practical effect experiment is carried out by applying a development design of the CPLD based on a low carrier ratio, the utilized CPLD has the advantages of easy development, good flexibility, high reliability, good expandability and high real-time performance, a 9-frequency multiplication modulation ratio is used in a low amplitude modulation ratio area, a 11-frequency multiplication modulation ratio is used in a high amplitude modulation ratio area, in addition, high-order harmonics can be reduced by a low-pass filter, low-order harmonics can also be effectively inhibited by the proposed low carrier ratio scheme, simulation and test results are used for researching the performance of a three-phase active front-end converter in designing the low carrier ratio PWM scheme, the low carrier ratio PWM scheme is applied, the service life of an inverter converter is prolonged, the power consumption is reduced, and the greening of electric inverter equipment is realized.
Drawings
FIG. 1 is a first formula diagram of the present invention;
FIG. 2 is a second formula diagram according to the present invention;
FIG. 3 is a bar graph of the SVPWM operation of the present invention at an amplitude modulation ratio ma of 0.8;
FIG. 4 is a histogram of the SPWM operation of the present invention at an amplitude modulation ratio ma of 0.4;
FIG. 5 is a bar graph of the amplitude modulation ratio ma of 0.8 according to the present invention;
FIG. 6 is a bar graph of the amplitude modulation ratio ma of 0.4 according to the present invention;
FIG. 7 is a graph of THD5, 7 of the present invention;
FIG. 8 is a graph of THD5, 7, 11, 13 of the present invention;
FIG. 9 is a graph of the spectral values of the low carrier ratio scheme of the present invention after passing through a low pass filter;
FIG. 10 is a graph of the SPWM data for the present invention at ma ═ 0.4;
fig. 11 is a graph of data for the results of the SVPWM operation of the present invention at ma ═ 0.8.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Specific examples are given below.
Based on the low carrier mixed harmonic elimination method of the active front-end converter of the new energy microgrid system, triple harmonic values are eliminated by the three-phase AFE converter, high-frequency-multiplication harmonics such as 17-frequency multiplication and 19-frequency multiplication are eliminated by the low-pass filter, the 5th, 7th, 11th and 13th low-order harmonic values which are the most difficult to solve are left, and Total Harmonic Distortion (THD) is defined as shown in the graph 1 and the graph 2;
THD operation different amplitude ratio values after passing through the low pass filter, comparing THD5, 7 and THD5, 7, 11, 13, THD5, 7, 11, 13, 17, 19 without the low pass filter are significantly increased, as in fig. 3 and 4;
FIG. 5 shows custom THD values at different amplitude modulation ratios; THD5, 7 harmonics are suppressed by the SVPWM scheme at 11 times frequency modulation ratio scheme in the amplitude modulation ratio region of 0.49< ma <1.0 as shown in fig. 5;
THD5, 7 is 0.35% at amplitude modulation ratio by SVPWM scheme, ma ═ 0.8;
the harmonics according to THD5, 7, 11, 13 are suppressed to 0.57< ma <1.0 in the amplitude modulation ratio region at 11 times the frequency modulation ratio by the SVPWM scheme, as shown in fig. 6;
when the amplitude ratio of operation is 0.9 at ma, THD5, 7, 11, 13 is 3.54%, when the 11 times frequency modulation ratio is controlled at high amplitude modulation ratio 0.57< ma <1.0, while the SPWM scheme is controlled at low amplitude modulation ratio 0.0< ma <0.57 at 9 times frequency modulation ratio, THD5, 7, 11, 13 is less than 30%;
we will separately study the harmonic and total harmonic distortion values after adding a low-pass filter to two modulation ratio schemes, such as the spectral values of the low-pass filter of the low carrier ratio PWM shown in fig. 7 and 8;
fig. 7 shows that the SVPWM scheme operates at spectral values with amplitude modulation ratio ma of 0.8, fig. 8 shows that the SPWM scheme operates at spectral values with amplitude modulation ratio ma of 0.4, the scheme with harmonics improved through the SPWM and the low pass filter is in the lower amplitude modulation ratio region, the scheme with better suppressed through the SVPWM and the low pass filter is in the higher amplitude modulation ratio region, and the spectral values with low carrier ratio after passing through the low pass filter are given.
As shown in fig. 9, when the SVPWM scheme with low carrier ratio passes through the low pass filter at the high amplitude modulation ratio ma of 0.8, the THD5, 7 is reduced from 0.35% to 0.2%, and the THD5, 7, 11, 13 is reduced from 7.3% to 1.3%;
when the low carrier ratio SPWM scheme passes through a low pass filter at a low amplitude modulation ratio ma of 0.4, THD5, 7 is reduced from 15.1% to 6.6% and THD5, 7, 11, 13 is reduced from 21.5% to 7.3%.
Results of the experiment
The controller of the experimental AFE consists of a TMS320F2833 digital signal processor DSP and a complex programmable logic controller CPLD with LCMXXO 2280, and the experimental results of the low carrier control scheme are shown in FIGS. 10 and 11;
the result is an experimental result graph displayed by a LeCroy oscilloscope, and the mixed design scheme can produce good effect in low carrier ratio global harmonic suppression.
A mixing method of 9 times and 11 times of lower carrier ratio is applied by combining the SPWM method and the SVPWM method, the low harmonic wave band of the SPWM and the low harmonic wave band of the SVPWM are found in the theoretical design, and switching control is carried out; and then, a practical effect experiment is carried out by applying a development design of the CPLD based on a low carrier ratio, the utilized CPLD has the advantages of easy development, good flexibility, high reliability, good expandability and high real-time performance, a 9-frequency multiplication modulation ratio is used in a low amplitude modulation ratio area, a 11-frequency multiplication modulation ratio is used in a high amplitude modulation ratio area, in addition, high-order harmonics can be reduced by a low-pass filter, low-order harmonics can also be effectively inhibited by the proposed low carrier ratio scheme, simulation and test results are used for researching the performance of a three-phase active front-end converter in designing the low carrier ratio PWM scheme, the low carrier ratio PWM scheme is applied, the service life of an inverter converter is prolonged, the power consumption is reduced, and the greening of electric inverter equipment is realized.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (4)
1. A low-carrier mixed harmonic elimination method based on an active front-end converter of a new energy microgrid system is characterized by comprising the following specific operation steps:
the method comprises the following steps: eliminating triple harmonic values through a three-phase AFE converter, and eliminating 17 frequency-doubled and 19 frequency-doubled high-frequency harmonic by a low-pass filter to obtain 5th, 7th, 11th and 13th low-order harmonic values;
step two: THD operation achieves different amplitude ratios after passing through a low pass filter, where THD5, 7 and THD5, 7, 11, 13 are compared;
step three: according to THD5, 7, 11, 13 harmonics are suppressed to obtain an amplitude modulation ratio region at 9 and 11 times of frequency modulation ratio by SVPWM scheme, the 9 times frequency modulation ratio is used in a low amplitude modulation ratio region, and the 11 times frequency modulation ratio is used in a high amplitude modulation ratio region.
2. The active front-end converter low-carrier mixed harmonic elimination method based on the new energy microgrid system as claimed in claim 1, wherein the THD5, 7 harmonics are suppressed by SVPWM scheme at 11 times frequency modulation ratio in the amplitude modulation ratio region of 0.49< ma <1.0, the THD5, 7 is 0.35% by SVPWM operation at amplitude modulation ratio, ma ═ 0.8.
3. The active front-end converter low-carrier mixed harmonic elimination method based on the new energy microgrid system as claimed in claim 1, wherein the THD5, 7, 11, 13 harmonics are suppressed by SVPWM at 11 times frequency modulation ratio in the amplitude modulation ratio region to be 0.57< ma <1.0, the THD5, 7 is 0.35% by SVPWM scheme at amplitude modulation ratio, ma ═ 0.8.
4. The active front-end converter low-carrier mixed harmonic elimination method based on the new energy microgrid system according to claim 1, characterized in that the THD5, 7, 11, 13 harmonics are suppressed to obtain an amplitude modulation ratio region at 11 times frequency modulation ratio through an SVPWM scheme, the amplitude modulation ratio region is 0.57< ma <1.0, when the amplitude ratio of operation is ma ═ 0.9, the THD5, 7, 11, 13 is 3.54%, when the 11 times frequency modulation ratio is controlled at high amplitude modulation ratio 0.57< ma <1.0, and when the SPWM scheme is controlled at 9 times frequency modulation ratio at low amplitude modulation ratio 0.0< ma <0.57, the THD5, 7, 11, 13 is less than 30%;
when the SVPWM scheme with low carrier ratio is passed through the low pass filter at high amplitude modulation ratio ma of 0.8, THD5, 7 is reduced from 0.35% to 0.2%, and THD5, 7, 11, 13 is reduced from 7.3% to 1.3%;
when the low carrier ratio SPWM scheme passes through a low pass filter at a low amplitude modulation ratio ma of 0.4, THD5, 7 is reduced from 15.1% to 6.6% and THD5, 7, 11, 13 is reduced from 21.5% to 7.3%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111101973.0A CN113872207A (en) | 2021-09-18 | 2021-09-18 | Low-carrier mixed harmonic elimination method based on active front-end converter of new energy microgrid system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111101973.0A CN113872207A (en) | 2021-09-18 | 2021-09-18 | Low-carrier mixed harmonic elimination method based on active front-end converter of new energy microgrid system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113872207A true CN113872207A (en) | 2021-12-31 |
Family
ID=78992967
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111101973.0A Pending CN113872207A (en) | 2021-09-18 | 2021-09-18 | Low-carrier mixed harmonic elimination method based on active front-end converter of new energy microgrid system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113872207A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104298107A (en) * | 2014-08-26 | 2015-01-21 | 苏州科技学院 | Combined local frequency multiplication sampling algorithm for generating SPWM waves |
| CN109802586A (en) * | 2019-01-22 | 2019-05-24 | 中国科学院电工研究所 | Three-level current transformer synchronizes 3 times of SVPWM carrier wave implementation methods for several times |
| CN111641363A (en) * | 2020-06-18 | 2020-09-08 | 浙江工业大学 | Dead-beat control method for permanent magnet synchronous motor under low carrier ratio |
-
2021
- 2021-09-18 CN CN202111101973.0A patent/CN113872207A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104298107A (en) * | 2014-08-26 | 2015-01-21 | 苏州科技学院 | Combined local frequency multiplication sampling algorithm for generating SPWM waves |
| CN109802586A (en) * | 2019-01-22 | 2019-05-24 | 中国科学院电工研究所 | Three-level current transformer synchronizes 3 times of SVPWM carrier wave implementation methods for several times |
| CN111641363A (en) * | 2020-06-18 | 2020-09-08 | 浙江工业大学 | Dead-beat control method for permanent magnet synchronous motor under low carrier ratio |
Non-Patent Citations (1)
| Title |
|---|
| 陈祥: "微电网电源经济性规划与电能质量改善的研究", 中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑, no. 06, pages 042 - 487 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Dursun et al. | LCL filter design for grid connected three-phase inverter | |
| CN103532420B (en) | Dual-three-level online-topology switchable inverter | |
| Li et al. | Use of hybrid PWM and passive resonant snubber for a grid-connected CSI | |
| CN107196491B (en) | A kind of double buck gird-connected inverter half period current distortion inhibition system and method | |
| CN106787895B (en) | Parallel three phase inversion system circulation inhibition method based on SVM strategy | |
| CN103647470B (en) | A kind of three-phase NPC photovoltaic combining inverter based on Repetitive controller | |
| CN107508483A (en) | A kind of discontinuous pulse duration modulation method of three-level current transformer for reducing switching loss | |
| CN106981999A (en) | LLCCL type NPC inverter control systems and inverter side current resonance suppressing method | |
| Parimalasundar et al. | Investigation of efficient multilevel inverter for photovoltaic energy system and electric vehicle applications | |
| CN103124074B (en) | A kind of power quality compound compensation method | |
| Bhattacharya et al. | Active filters for harmonics elimination in solar photovoltaic grid-connected and stand-alone systems | |
| CN113872207A (en) | Low-carrier mixed harmonic elimination method based on active front-end converter of new energy microgrid system | |
| CN102013681A (en) | Three-phase solar inversion output waveform dynamic compensation control method | |
| CN116846202A (en) | Negative sequence current suppression system and method based on network construction type converter | |
| Wang et al. | A novel carrier-based PWM without narrow pulses applying to high-frequency link matrix converter | |
| CN106505898A (en) | Z sources NPC three-level inverter invariable power grid-connection control systems based on SVPWM | |
| CN106130383B (en) | A kind of coupling inductance photovoltaic combining inverter drain current suppressing method | |
| Soomro et al. | Optimal design of a single-phase APF based on PQ theory | |
| CN202817788U (en) | Grid-connected photovoltaic power generation system | |
| CN202221967U (en) | Three-phase PWM (pulse width modulation) rectifying device based on novel space vector algorithm | |
| CN113629712A (en) | Common mode rejection and characteristic improvement method of active power filter | |
| CN113629985B (en) | Submodule capacitor optimization control method of CHB-QAB topological structure | |
| CN104953615A (en) | Unified controller and control method of single-stage Z-source photovoltaic grid-connected inverter | |
| Cao et al. | A simple approach to current THD prediction for small-scale grid-connected inverters | |
| CN115276433A (en) | Hydrogen production converter |
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 |