CN112271912A - Active damping method for inhibiting dead zone harmonic waves on low-voltage side of power electronic transformer - Google Patents
Active damping method for inhibiting dead zone harmonic waves on low-voltage side of power electronic transformer Download PDFInfo
- Publication number
- CN112271912A CN112271912A CN202011246866.2A CN202011246866A CN112271912A CN 112271912 A CN112271912 A CN 112271912A CN 202011246866 A CN202011246866 A CN 202011246866A CN 112271912 A CN112271912 A CN 112271912A
- Authority
- CN
- China
- Prior art keywords
- low
- power electronic
- dead zone
- electronic transformer
- active damping
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 38
- 238000013016 damping Methods 0.000 title claims abstract description 35
- 230000002401 inhibitory effect Effects 0.000 title abstract description 6
- 238000005516 engineering process Methods 0.000 claims abstract description 15
- 230000001629 suppression Effects 0.000 claims abstract description 15
- 230000000694 effects Effects 0.000 claims abstract description 10
- 238000012937 correction Methods 0.000 claims abstract description 7
- 238000012546 transfer Methods 0.000 claims description 19
- 230000000052 comparative effect Effects 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 10
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000004088 simulation Methods 0.000 description 4
- 238000002955 isolation Methods 0.000 description 3
- 238000005457 optimization Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 230000003252 repetitive effect Effects 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000033772 system development Effects 0.000 description 1
Images
Classifications
-
- 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
- H02M7/53—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 using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/537—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
- H02M7/5387—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
- H02M7/53871—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current
- H02M7/53875—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current with analogue control of three-phase output
-
- 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)
- Supply And Distribution Of Alternating Current (AREA)
- Inverter Devices (AREA)
Abstract
The invention discloses an active damping method for inhibiting dead zone harmonics at the low-voltage side of a power electronic transformerADAnd selecting an active resistance value RADAfter current proportion feedforward of an active damping technology is realized, current control is corrected, a correction link is connected in series behind a controller, and suppression of harmonic waves of a dead zone on the low-voltage side of the power electronic transformer is completed. The method of the invention uses the active damping technology to improve the low-frequency impedance of the LCL filter, has simple realization principle and improves the effect of inhibiting the low-frequency harmonic component introduced by the dead zone in the DC/AC converter of the low-voltage side of the power electronic transformer based on the LCL filter.
Description
Technical Field
The invention relates to the technical field of power electronic transformers, in particular to an active damping method for suppressing dead zone harmonics on the low-voltage side of a power electronic transformer.
Background
Compared with the traditional power transformer, the Power Electronic Transformer (PET) not only can realize the functions of voltage grade conversion, electrical isolation, energy transfer and the like, but also can realize additional functions of power flow control, electric energy quality control and the like, and is a trend of future power system development. When the DC/AC converter outputs fundamental wave (power frequency 50Hz) component voltage, the switch working mode of the DC/AC converter can introduce switch sub-high frequency harmonic in the output voltage of the three-phase inverter bridge, and the large high frequency impedance of the LCL filter can obviously filter the high frequency harmonic; the dead zone added for preventing the inverter bridge from being directly connected generates a large amount of low-frequency harmonic components, and the low-frequency impedance of the LCL filter is small, so that the suppression capability of the LCL filter is limited.
The traditional dead zone harmonic suppression method mainly comprises two types, namely dead zone compensation and optimization control. The dead zone compensation method starts from the modulation process of the switch, analyzes the magnitude of harmonic voltage caused by the dead zone and adjusts the magnitude of the modulation wave according to the harmonic voltage, so that the suppression of the dead zone harmonic is realized. However, the harmonic voltage caused by the dead zone is related to the direction of the current, the nonlinearity of the switching device, the fluctuation of the direct current bus voltage and other factors, and the implementation difficulty of accurate dead zone compensation is high. The method for optimizing control starts from the design and optimization of a current controller, such as a resonance controller, a repetitive controller and the like which are reasonably designed, and essentially improves the equivalent impedance of an inverter, so that smaller harmonic current is generated under the same dead zone harmonic voltage. The optimization control methods can achieve better effects, but the principle is complex and troublesome to implement, and the research and development period is long.
Disclosure of Invention
Aiming at the defects and shortcomings of the prior art, the invention provides an active damping method for inhibiting dead zone harmonics at the low-voltage side of a power electronic transformer.
The purpose of the invention can be realized by the following technical scheme:
an active damping method for suppressing dead zone harmonics on the low-voltage side of a power electronic transformer comprises the following steps:
step 1: the model of the LCL filter is simplified, the low-voltage side DC/AC converter of the power electronic transformer is provided with the LCL filter, and the three-phase inverter bridge outputs the voltage V to the grid-connected current IgThe transfer function of (a) is:
the LCL filter is simplified into a first-order system, and the transfer function of the LCL filter is as follows:
step 2: selecting an active resistance value RADIntroducing an active resistor RADThe transfer function is then approximately equivalent to:
wherein R isADThe value of (a) significantly affects the frequency range of harmonic suppression, RADThe values of (A) are as follows:
RAD≥2πnf1_max(L1+L2)
wherein f is1_maxThe maximum value is taken when the voltage frequency fluctuation of the power grid is considered; n is the highest order of the low frequency harmonics to be suppressed.
And step 3: realizing current proportion feedforward of active damping technology, detecting current I of inversion side in control systemL1And a given V is output by the inverter bridgerefMinus IL1And RADThe product of (a).
And 4, step 4: correcting current control, and after adopting an active damping technology, approximating and equating a transfer function as:
wherein,
for time-delay links of digital control systems, TsIs the sampling period of the control system. Comparative GAD_d(s) and G(s), it is known that the transfer function of the controlled object changes from before after the active damping method is adopted.
In order to realize the same current control effect, a correction link is connected in series behind a controller, and the suppression of the harmonic waves of the dead zone at the low-voltage side of the power electronic transformer is completed at the same time, wherein the correction link process is as follows:
further, step 2 utilizes an active damping technique to increase the low-frequency impedance of the LCL filter, thereby suppressing the low-frequency harmonic component introduced by the dead zone in the DC/AC converter based on the LCL filter on the low-voltage side of the power electronic transformer.
Further, in the step 2, n can consider the requirement on the frequency of the fundamental wave of 50 times in the relevant standard of the power quality according to the required value, and the value of n is recommended to meet the condition that n is more than or equal to 50.
The invention has the beneficial technical effects that:
1. the low-frequency impedance of the LCL filter is increased by connecting resistors in series, so that the suppression capability of the LCL filter on dead zone harmonics is obviously improved.
2. The control effect achieved by using the active damping technology in the control is equivalent to that of a series resistor in an actual circuit, and no additional power loss is introduced.
3. Introducing an active damping technology and selecting a proper active resistance value RADThe low-frequency impedance of the LCL filter can be obviously improved, so that low-frequency harmonics introduced by dead zones in the DC/AC converter based on the LCL filter at the low-voltage side of the power electronic transformer can be restrainedA wave component.
Drawings
Fig. 1 is a power electronic transformer topology diagram of the active damping method for suppressing dead zone harmonics on the low voltage side of the power electronic transformer according to the present invention.
FIG. 2 is a schematic diagram of an LCL filter-based DC/AC converter on the low-voltage side of a power electronic transformer for the active damping method for suppressing dead zone harmonics on the low-voltage side of the power electronic transformer according to the present invention
Fig. 3 is a flow chart of the active damping method for suppressing dead zone harmonics on the low-voltage side of the power electronic transformer according to the present invention.
FIG. 4 shows the transfer function G of the LCL filter of the active damping method for suppressing the dead zone harmonic on the low voltage side of the power electronic transformer according to the present inventionLCL(s) bode diagram of its simplified form g(s).
FIG. 5 shows that the active resistance R is added in the active damping method for suppressing the dead zone harmonic wave on the low voltage side of the power electronic transformerADSimplified form G of post-LCL filterADBode diagram of(s).
Fig. 6 is a grid-tied current control topology without the active resistance technique.
Fig. 7 is a grid-connected current control topological diagram adopting an active resistance technology of the active damping method for suppressing the dead zone harmonic on the low-voltage side of the power electronic transformer.
Fig. 8 is a grid-connected current simulation result of grid-connected current control without using the active resistance technique.
Fig. 9 is a grid-connected current simulation result of the grid-connected current control using the active resistance technique according to the active damping method for suppressing the dead zone harmonic on the low-voltage side of the power electronic transformer of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.
The topological diagram of the power electronic transformer applied by the invention is shown in figure 1, and the power electronic transformer is provided with a medium-voltage alternating current port, a high-voltage alternating current port and a low-voltage alternating current port. The middle-voltage AC port side and the high-voltage AC port side are of modular structures, the A, B, C three-phase module is respectively composed of N modules, H bridges of the N modules of each phase are connected in series to form an input stage of a Cascade H Bridge (CHB) structure, and AC/DC conversion is realized; the direct current bus of each H bridge is connected with the low-voltage direct current bus through a series resonance type double-active H bridge isolation converter, and DC/DC conversion and isolation are realized. And on the side of the low-voltage alternating current port, the AC/DC converter is connected with a low-voltage direct current bus and a low-voltage alternating current power grid to realize DC/AC conversion.
Fig. 2 shows a schematic diagram of a DC/AC converter based on an LCL filter on the low-voltage side of a power electronic transformer, wherein the DC/AC converter outputs fundamental wave (power frequency 50Hz) component voltage, and the switching mode of the DC/AC converter introduces switching sub-high frequency harmonics into the output voltage of a three-phase inverter bridge, and the large high frequency impedance of the LCL filter can significantly filter the high frequency harmonics. In addition, the dead zone added for preventing the inverter bridge from being directly connected generates a large amount of low-frequency harmonic components, and the low-frequency impedance of the LCL filter is small, so that the suppression capability of the LCL filter is limited.
FIG. 3 shows a flow of steps for implementing the present invention, introducing active damping technique and selecting a suitable active resistance value RADThe low-frequency impedance of the LCL filter is obviously improved, so that low-frequency harmonic components introduced by dead zones in the DC/AC converter based on the LCL filter on the low-voltage side of the power electronic transformer are suppressed.
The invention discloses an active damping method for inhibiting dead zone harmonics at the low-voltage side of a power electronic transformer, which comprises the following steps of:
step 1: the LCL filter model is simplified. The low-voltage side DC/AC converter of the power electronic transformer is provided with an LCL filter, and a three-phase inverter bridge outputs a voltage V to a grid-connected current IgThe transfer function of (a) is:
the above equation shows that the LCL filter is a third order system with a transfer function GLCLThe bode diagram of(s) is shown in fig. 4. From fig. 4, the high frequency resistance of the LCL filter can be seenThe impedance is large, so that the filter has a good high-frequency filtering effect; however, the low-frequency impedance is small, and thus the suppression capability of the low-frequency harmonic component is limited. Harmonic components introduced by dead zones in the DC/AC converter are mainly low frequencies, for which the LCL filter has a limited suppression capability.
To simplify the analysis of the low frequency band, the LCL filter is simplified to a first order system, whose transfer function is:
a bode plot of a simplified form g(s) of the LCL filter transfer function is shown in fig. 4.
Step 2: selecting an active resistance value RAD. The low-frequency impedance of the LCL filter can be remarkably increased by connecting resistors in series in the LCL filter, and the suppression capability of the LCL filter on dead zone harmonics can be remarkably improved. In the introduction of an active resistor RADThe transfer function is then approximately equivalent to:
increasing the active resistance RADSimplified form G of post-LCL filterADThe bode diagram of(s) is shown in FIG. 5, knowing that GAD(s) comprises two asymptotes, the intersection of which is called the turning point, and the angular frequency of which is:
on the left side of the turning point (direction of decreasing frequency), GADThe bode diagram of(s) is dominated by the active resistance RADIndicates that R isADThe low-frequency impedance of the LCL filter can be obviously increased; to the right of the turning point, RADThe influence of (c) is small. This indicates that RADThe value of (a) significantly affects the frequency range of harmonic suppression, and a proper active resistance value R should be selectedAD。
RADIs taken as：
RAD≥2πnf1_max(L1+L2)
Wherein f is1_maxThe maximum value is taken when the voltage frequency fluctuation of the power grid is considered; n is the highest order of the low frequency harmonics to be suppressed. n can be selected as the active resistance value R according to the demand value by considering the requirement on 50 fundamental wave frequencies in the relevant standard of the power qualityADAt least 50 fundamental wave frequencies are restrained, and the value of n is recommended to satisfy n more than or equal to 50.
And step 3: and realizing the current proportion feedforward of the active damping technology. The current in the actual circuit will generate voltage drop at two ends of the resistor after flowing through the resistor, and in order to realize the same effect, the current I on the inversion side is detected in the control systemL1And a given V is output by the inverter bridgerefMinus IL1And RADThe product of (a).
The grid-connected current control topological graph without the active resistance technology and the grid-connected current control topological graph with the active resistance technology are respectively shown in fig. 6 and fig. 7, wherein fig. 7 shows the details of the current proportional feedforward implementation of the active damping technology. The control effect achieved by using the active damping technique in the control is equivalent to the series resistance in the actual circuit, and no additional power loss is introduced.
And 4, step 4: the current control is corrected. After the active damping technique is adopted, the transfer function is approximately equivalent to:
wherein,
for time-delay links of digital control systems, TsIs the sampling period of the control system. Comparative GAD_d(s) and G(s), it is known that the transfer function of the controlled object changes from before after the active damping method is adopted.
In order to realize the same current control effect, a correction link is connected in series behind a controller, and the suppression of the harmonic waves of the dead zone at the low-voltage side of the power electronic transformer is completed at the same time, wherein the correction link process is as follows:
fig. 7 shows the position of the calibration segment.
The grid-connected current simulation result of grid-connected current control without adopting the active resistance technology and the grid-connected current simulation result of grid-connected current control adopting the active resistance technology are respectively shown in fig. 8 and 9, the current waveform of fig. 8 contains a large amount of low-frequency harmonics, while the current waveform of fig. 9 adopting the method of the invention is closer to sine, the low-frequency harmonic components are obviously reduced, and the effectiveness of the invention is shown.
The above-mentioned embodiments are illustrative of the specific embodiments of the present invention, and are not restrictive, and those skilled in the relevant art can make various changes and modifications to obtain corresponding equivalent technical solutions without departing from the spirit and scope of the present invention, so that all equivalent technical solutions should be included in the scope of the present invention.
Claims (3)
1. An active damping method for suppressing dead zone harmonics on the low-voltage side of a power electronic transformer is characterized by comprising the following steps:
step 1: the model of the LCL filter is simplified, the low-voltage side DC/AC converter of the power electronic transformer is provided with the LCL filter, and the three-phase inverter bridge outputs the voltage V to the grid-connected current IgThe transfer function of (a) is:
the LCL filter is simplified into a first-order system, and the transfer function of the LCL filter is as follows:
step 2: selecting an active resistance value RADIntroducing an active resistor RADThe transfer function is then approximately equivalent to:
wherein R isADThe value of (a) significantly affects the frequency range of harmonic suppression, RADThe values of (A) are as follows:
RAD≥2πnf1_max(L1+L2)
wherein f is1_maxThe maximum value is taken when the voltage frequency fluctuation of the power grid is considered; n is the highest order of the low frequency harmonics to be suppressed.
And step 3: realizing current proportion feedforward of active damping technology, detecting current I of inversion side in control systemL1And a given V is output by the inverter bridgerefMinus IL1And RADThe product of (a).
And 4, step 4: correcting current control, and after adopting an active damping technology, approximating and equating a transfer function as:
wherein,
for time-delay links of digital control systems, TsIs the sampling period of the control system. Comparative GAD_d(s) and G(s), it is known that the transfer function of the controlled object changes from before after the active damping method is adopted.
In order to realize the same current control effect, a correction link is connected in series behind a controller, and the suppression of the harmonic waves of the dead zone at the low-voltage side of the power electronic transformer is completed at the same time, wherein the correction link process is as follows:
2. the active damping method for suppressing the dead zone harmonics on the low-voltage side of the power electronic transformer as recited in claim 1, wherein said step 2 employs an active damping technique to raise the low-frequency impedance of the LCL filter, thereby suppressing the low-frequency harmonic components introduced by the dead zone in the LCL filter-based DC/AC converter on the low-voltage side of the power electronic transformer.
3. The active damping method for suppressing the dead zone harmonic waves on the low-voltage side of the power electronic transformer as claimed in claim 1, wherein n in step 2 can consider the requirement on the frequency of 50 fundamental waves in the power quality related standard according to a required value, and the value of n is recommended to meet n ≥ 50.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011246866.2A CN112271912B (en) | 2020-11-10 | 2020-11-10 | Active damping method for inhibiting dead zone harmonic waves at low-voltage side of power electronic transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011246866.2A CN112271912B (en) | 2020-11-10 | 2020-11-10 | Active damping method for inhibiting dead zone harmonic waves at low-voltage side of power electronic transformer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112271912A true CN112271912A (en) | 2021-01-26 |
| CN112271912B CN112271912B (en) | 2022-09-27 |
Family
ID=74339788
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011246866.2A Active CN112271912B (en) | 2020-11-10 | 2020-11-10 | Active damping method for inhibiting dead zone harmonic waves at low-voltage side of power electronic transformer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112271912B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101950983A (en) * | 2010-10-08 | 2011-01-19 | 天津理工大学 | Two-stage photovoltaic grid-connected control system based on combination of pole allocation and repetitive control |
| CN201813171U (en) * | 2010-10-08 | 2011-04-27 | 天津理工大学 | Two-stage photovoltaic grid-connected control device based on pole assignment and repetitive control combination |
| CN102290820A (en) * | 2011-08-22 | 2011-12-21 | 中国矿业大学 | LCL (Lower Control Unit) filtering controlled rectifying active damping control method of electric currents on feedback variable current side |
| CN103516248A (en) * | 2013-09-26 | 2014-01-15 | 武汉大学 | LLCL smoothing grid-connected inverter based on single electric current loop control |
| CN105186573A (en) * | 2015-10-27 | 2015-12-23 | 夏百战 | Current control system based on LCL filter technology |
| JP2018182811A (en) * | 2017-04-05 | 2018-11-15 | 富士電機株式会社 | Power converter and control device therefor |
| CN109004649A (en) * | 2018-06-29 | 2018-12-14 | 南京理工大学 | A kind of LCL filter resonance inhibition device and method based on active damping |
-
2020
- 2020-11-10 CN CN202011246866.2A patent/CN112271912B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101950983A (en) * | 2010-10-08 | 2011-01-19 | 天津理工大学 | Two-stage photovoltaic grid-connected control system based on combination of pole allocation and repetitive control |
| CN201813171U (en) * | 2010-10-08 | 2011-04-27 | 天津理工大学 | Two-stage photovoltaic grid-connected control device based on pole assignment and repetitive control combination |
| CN102290820A (en) * | 2011-08-22 | 2011-12-21 | 中国矿业大学 | LCL (Lower Control Unit) filtering controlled rectifying active damping control method of electric currents on feedback variable current side |
| CN103516248A (en) * | 2013-09-26 | 2014-01-15 | 武汉大学 | LLCL smoothing grid-connected inverter based on single electric current loop control |
| CN105186573A (en) * | 2015-10-27 | 2015-12-23 | 夏百战 | Current control system based on LCL filter technology |
| JP2018182811A (en) * | 2017-04-05 | 2018-11-15 | 富士電機株式会社 | Power converter and control device therefor |
| CN109004649A (en) * | 2018-06-29 | 2018-12-14 | 南京理工大学 | A kind of LCL filter resonance inhibition device and method based on active damping |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112271912B (en) | 2022-09-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104836232B (en) | Frequency wide-range self-adaptive repetition control method of active power filter | |
| CN108879906A (en) | Modularized medium-voltage quick charger | |
| CN110429603B (en) | Six-switch seven-level active power filter and compensation method | |
| Darwish et al. | Current-source single-phase module integrated inverters for PV grid-connected applications | |
| CN104410074B (en) | A kind of based on PI adaptive Active Power Filter-APF composite control method | |
| CN111490695B (en) | Single-stage low-voltage stress switch capacitance type multi-level inverter topology structure and level modulation method | |
| CN107800135B (en) | Different-order harmonic refinement compensation method for SAPF | |
| Turksoy et al. | A novel adaptive switching method to reduce DC-Link capacitor ripple in PV based grid-connected inverter | |
| CN112532094A (en) | Compound control method of T-type three-level NPC inverter | |
| CN107968406B (en) | Anti-saturation frequency self-adaptive repetitive control method for active power filter | |
| CN111431176B (en) | Closed-loop control method of universal power quality controller based on self-adaptive control | |
| CN112271912B (en) | Active damping method for inhibiting dead zone harmonic waves at low-voltage side of power electronic transformer | |
| CN110417016B (en) | Inverter, power generation system and method for inhibiting harmonic distortion of alternating current system | |
| CN111030483A (en) | Power electronic transformer and control method | |
| Chen et al. | Research and implementation of single-phase AC electronic load based on quasi-PR control | |
| Helali et al. | Robustness of smart transformer based-on sliding mode controller under grid perturbations | |
| CN112701722B (en) | Active damping method for inhibiting grid-connected current dead zone harmonic of energy router | |
| Kortenbruck et al. | Harmonic voltage compensation with power electronic grid regulator based on symmetrical components | |
| Elhassan et al. | Investigation on multisampling deadbeat current control with time-delay compensation in grid-connected inverter | |
| Louganski et al. | A 20-kW, 10-kHz, single-phase multilevel active-front-end converter with reactive power control | |
| Sarhangzadeh et al. | Dynamic analysis of DVR implementation based on nonlinear control by IOFL | |
| Farhadi-Kangarlu et al. | Multilevel inverter based distribution statcom: Application of the cross-switched multilevel inverter | |
| Qiao et al. | Performance of three-phase inverter using multiple bidirectional choppers for 1.5-kV PV systems capable of wide MPPT range | |
| CN110061644B (en) | Suppression strategy for unbalanced current of isolated MMC bridge arm | |
| CN108696144A (en) | The modulation compensated circuit of interleaving inverse excitation type DC/DC hardware |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |