CN113315180B - Reactive power distribution method suitable for problem of power imbalance among modules in photovoltaic power generation - Google Patents
Reactive power distribution method suitable for problem of power imbalance among modules in photovoltaic power generation Download PDFInfo
- Publication number
- CN113315180B CN113315180B CN202110620791.8A CN202110620791A CN113315180B CN 113315180 B CN113315180 B CN 113315180B CN 202110620791 A CN202110620791 A CN 202110620791A CN 113315180 B CN113315180 B CN 113315180B
- Authority
- CN
- China
- Prior art keywords
- module
- power
- reactive power
- output
- modules
- 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.)
- Active
Links
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
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
- H02J3/50—Controlling the sharing of the out-of-phase component
-
- 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
- H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
- H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
- H02J2203/10—Power transmission or distribution systems management focussing at grid-level, e.g. load flow analysis, node profile computation, meshed network optimisation, active network management or spinning reserve management
-
- 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
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/22—The renewable source being solar energy
- H02J2300/24—The renewable source being solar energy of photovoltaic origin
-
- 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
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Electrical Variables (AREA)
Abstract
The invention discloses a reactive power distribution method suitable for solving the problem of power imbalance among modules in photovoltaic power generation. In the photovoltaic medium-voltage cascade converter structure, when an unbalance phenomenon caused by unequal active power generated by each module occurs, the amplitude of the output voltage of each module can be adjusted in a mode of injecting a certain amount of reactive power into a system so as to effectively reduce the overmodulation phenomenon. The reactive power distribution mode of the invention ensures that each module does not have overmodulation, simultaneously realizes the balance of apparent power of each module of the system to the maximum extent, and reduces the difference of power born by each module.
Description
Technical Field
The invention relates to the technical field of medium-voltage photovoltaic power generation power conversion, in particular to a reactive power distribution method suitable for solving the problem of power imbalance among modules in photovoltaic power generation.
Background
One key indicator in photovoltaic power generation applications is power generation efficiency. The traditional solution of large photovoltaic power station converters is mainly a centralized power generation architecture. The centralized power generation is a converter structure which is subjected to high-voltage direct current convergence and then centralized inversion, and a schematic diagram of the converter structure is shown in fig. 1. In a photovoltaic power station with a centralized framework, in order to realize boosting and electrical isolation, a heavy power frequency alternating current boosting transformer is needed, and the transformer has the problems of high no-load loss and the like, so that the efficiency of a medium-voltage photovoltaic system is reduced.
The cascade type isolation converter can avoid using a power frequency transformer in the traditional scheme, and meanwhile, the modular design can effectively reduce the production and manufacturing cost and improve the reliability and the expansibility of the system. A schematic diagram of a cascaded isolated converter is shown in fig. 2. The existing photovoltaic medium-voltage cascade conversion system has the problem of power imbalance, and along with the change of illumination intensity, service time and the like, the output power and the voltage of a photovoltaic cell panel are also changed, so that the output power of each module is possibly unbalanced, the output of the module is possibly overmodulation, and the photovoltaic converter is further caused to be in fault shutdown. In order to obtain as long a power generation time as possible, the cascaded converters are required to work properly even in the case of power imbalance. In a traditional framework, all photovoltaic panels are connected to the same direct current bus, power can flow among modules, and the overmodulation problem caused by power imbalance does not exist. However, there is no common DC bus in the two-stage architecture discussed in this patent, so the overmodulation problem needs to be avoided by the Control strategy (see, in particular, Implementation of a 3.3-kW DC-DC Converter for EV On-Board Charger applying the Series-resonance With Reduced-Frequency-Range Control). The current common idea is to widen the range of power imbalances that the cascaded converters tolerate by making the cascaded converters either output or absorb reactive power. In the published literature, two control strategies that are representative are Reactive Power Sharing (RPS) and Apparent Power Sharing (APS) strategies. The RPS strategy is to make the reactive power output by each module the same, and the APS strategy is to make the apparent power output by each module the same.
The range of power imbalance that can be handled by the above control method is relatively limited, and even if overmodulation can be prevented, it is difficult to improve the problem of the total apparent power imbalance among the modules. Therefore, an object of the present invention is to provide a new reactive power distribution method, which can maximize the balance of the apparent power of each module and reduce the variance while expanding the range of the power imbalance that can be handled.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a reactive power distribution method suitable for the problem of power imbalance among modules in photovoltaic power generation, which can expand the range of power imbalance which can be processed and can keep the balance of apparent power born by each module to the maximum extent.
The invention is realized by adopting the following technical scheme:
a reactive power distribution method suitable for the problem of power imbalance among modules in photovoltaic power generation aims at a photovoltaic power generation system adopting a cascade converter and knows active power P generated by each modulek1、Pk2…PkNAnd total reactive power Q of system required outputgUnder the condition (1), the reactive power distributed to each module is calculated according to the following formula:
wherein N is the number of modules cascaded in the system; sequencing the modules from small to large according to the active power sent by the modules, wherein the sequenced module is a module k1、k2…kNSatisfy active power Pk1≤Pk2≤…≤PkN;kmIndicating the kth in the systemmM is more than or equal to 1 and less than or equal to N, QkmRepresents its reactive power; pgRepresenting the total active power, V, output by the modules in the systemgRepresenting the grid voltage, VmaxIndicating the maximum voltage, S, allowed to be output by each moduleequIs determined by the following formula:
x is the number of modules which need to output reactive power when the power is not used; srefThe apparent power of the modules is the apparent power of the N modules at the moment; srefIs determined by the following formula:
wherein P isiRepresenting the active power of the ith module in the system.
In the above technical solution, further, the reactive power distribution method specifically includes:
1) when discriminant
When the system meets the requirement, the system does not need to perform reactive power control;
2) when discriminant
When satisfied, only module k1Reactive power needs to be output, then the module k is at this time1Satisfies the following conditions:
at this time, the situation of the reactive power output by each module is as follows:
when discriminant
When satisfied, module k2Reactive power output is also required initially and module k needs to be guaranteed1、k2Is equal, then it needs to be satisfied that:
at this time, the situation of the reactive power output by each module is as follows:
by analogy, when the discriminant
When satisfied, module kxAlso, there is an initial need to output reactive power, x<N, and the module k needs to be guaranteed1、k2…kxIs equal, then it needs to be satisfied that:
at this time, the situation of the reactive power output by each module is as follows:
3) when discriminant
When satisfied, module k at this time1、k2…kN-1The output reactive power can not meet the requirement of the system, and the module kNReactive power also needs to be output; at this time, in order to ensure the balance of the system, the apparent power of the N modules is ensured to be equal when distributing the reactive power, and the balance is ensured according to SrefThe value of (2) is used for solving the reactive power required to be output by each module:
the invention has the beneficial effects that:
after the total amount of reactive power injected into the system is determined, the invention distributes the reactive power into each module by adopting a mode of ensuring the power balance among the modules to the maximum extent: suppose that the total reactive power to be distributed is QgFirstly, the modules are sorted according to the active power of the modules, and the sorted modules are assumed to be k1,k2…kNSatisfy Pk1≤Pk2≤…≤PkNThen the slave module k1Starting to distribute reactive power; when it is a module k1The distributed reactive power is such that its apparent power reaches module k2Active power of, moreover, QgIf there is a remainder, then it starts to be the module k at the same time1、k2Distributing reactive power and keeping the apparent power of the two equal; when it is a module k1、k2Distributed reactive power is such that k1、k2Apparent power reaches module k3Active power of, moreover, QgIf there is a remainder, then it starts to be the module k at the same time1、k2、k3Distributing reactive power and keeping the apparent power of the three equal … … and so on until QgAnd after distribution is completed or all the N modules need to output reactive power. The reactive power distribution mode provided by the invention ensures that each module does not have overmodulation, realizes the balance of apparent power of each module of the system to the maximum extent and reduces the difference of power born by each module.
Drawings
Fig. 1 is a schematic structural diagram of a conventional concentrated photovoltaic power plant.
Fig. 2 is a schematic diagram of a cascade-type converter.
Fig. 3 is a schematic diagram of a photovoltaic medium voltage cascaded converter control system suitable for power imbalance among modules according to the invention.
FIG. 4 is a schematic diagram of the dq0 and d 'q'0 coordinate axes as a function of phasors in the system.
Detailed Description
Fig. 3 is a schematic diagram of a control method of a photovoltaic medium voltage cascaded converter suitable for power imbalance between power conversion modules according to the present invention. In order to avoid overmodulation caused by power imbalance and prolong the power generation time, a certain control strategy needs to be adopted by a cascade converter control system. A common idea is to widen the range of power imbalances that the cascaded converters tolerate by making them output or absorb reactive power. The control system of the control method of the invention is composed of a direct current voltage control module 101, a reactive power calculation module 102, an output current control module 103, a voltage component calculation module 104, a modulation module 105, an active power sequencing module 106 and a reordering module 107. The input of the DC voltage control module 101 is the DC voltage V of each moduledci(i ═ 1,2 … N), the output is the real power command value P for each modulei(i ═ 1,2 … N). Active power P of each modulei(i is 1,2 … N) to obtain the total active power Pg. The input of the reactive power calculation module 102 is the active power P of each module sequenced by the active power sequencing module 106ki( ki 1,2 … N), the output is the total reactive power Q of the systemgAnd the reactive power value Q of each moduleki( ki 1,2 … N). The input of the current control module 103 is total active power PgAnd total reactive power QgD-axis and q-axis current values i obtained by dividing the grid voltagedrefAnd iqrefThe output is the system output voltage vsThe magnitude of the components v on the d 'and q' axessd'And vsq'. The input to the voltage component calculation module 104 is vsd',vsq',Pg,Qg,Pi(i-1, 2 … N), and Q reordered by the reordering module 107i( i 1,2 … N), the output is the instantaneous voltage V of each modulesi(i=1,2…N)。VsiThe pulse PWM signals are converted into pulse PWM signals through the modulation module 105 and sent to each switching tube.
The d-q coordinate system refers to a coordinate system in which the d axis is flush with the voltage phasor of the power grid, and the q axis leads the d axis by 90 degrees; the d ' -q ' coordinate system refers to a coordinate system that the d ' axis is level with the grid-connected current phasor and the q ' axis leads the d ' axis by 90 degrees. A schematic of the relationship of the dq0 and d 'q'0 axes to the phasors in the system is shown in FIG. 4.
The reactive power calculation module 102 calculates the total reactive power required by the system according to the following formula:
where N is the number of power modules, VmaxMaximum voltage, V, allowed to be output for each modulegFor the mains voltage, SmaxIndicating the maximum apparent power, S, allowed by each modulerefIs a solution of the following equation:
k1,k2,...,kNis subscript, P, of each module sorted according to active powerkj(j ═ 1, 2.., N) denotes the subscript kjThe active power of the module of (a), namely:
Pk1≤Pk2≤…≤PkN (3)
the invention adopts different modes to carry out reactive power control aiming at different active power distribution conditions among the modules. When discriminant
When the requirement is met, the system does not need to perform reactive control at the moment, and therefore the required reactive power is 0.
When discriminant
When the system is satisfied, the system needs to perform reactive power control at the moment so as not to overshootIn the case of braking, in the module k with the highest active powerNWithout outputting reactive power, i.e. QkN0, and module kNHas an output voltage of VmaxI.e. VkN=VmaxThe required reactive power can then take a minimum value, which is calculated according to the following formula:
in order to avoid over-modulation of the power module and to minimize the reactive power, the required reactive power Q is determined when the criterion (5) is satisfiedgCalculated according to equation (6).
When discriminant
When satisfied, it indicates that if the module k is presentNReactive power is not output, and reactive power is output only by the rest N-1 modules, so that the reactive power imbalance of the system cannot be adapted. There is therefore a need to further increase the reactive output capability of the system. While increasing the reactive power, the voltage of each module is required to be ensured not to exceed Vmax. The apparent power S of each module is controlled at the momentiSame according to the formula
It can be known that when the apparent power S of each moduleiAt the same time, the voltage V of each moduleiThe same applies. Assume that the apparent power of each module is SrefControlling the voltage of all the modules to be VmaxThe following equation can be obtained:
satisfies the criterion (7)Then, S is calculated from equation (9)refAnd controlling the apparent power of each module to be Sref。
The reactive power calculation module (102) calculates the required reactive power Q of each module in the system according to the following formulakm:
Wherein SequIs determined by the following formula:
first, if the criterion (4) is satisfied, it is shown that the system can be stabilized without injecting reactive power into the system, and thus each module does not need to output reactive power naturally.
When the criterion (5) is satisfied, it indicates that the system needs to output a certain amount of reactive power to prevent over-modulation, and when distributing the reactive power, the following principle is followed:
1. distributing from the module with the minimum output active power, and increasing the number of distributed modules according to the sequence of the active power from small to large until the distribution is finished or the module with the maximum active power starts to output reactive power;
2. ensuring that the apparent power of all modules needing to output reactive power is equal;
3. the apparent power of the module which needs to output the reactive power does not exceed the active power of any other module which does not output the reactive power.
I.e. first module k1Distributing reactive power; when it is a module k1The distributed reactive power is such that its apparent power reaches module k2Active power of, moreover, QgIf there is a remainder, then it starts to be the module k at the same time1、k2Distributing reactive power and keeping the apparent power of the two equal; when it is a module k1、k2Distributed reactive power enables module k1、k2Apparent powerRate reaches module k3Active power of, moreover, QgIf there is a remainder, then it starts to be the module k at the same time1、k2、k3Reactive power is distributed and the apparent power of the three is kept equal … … and so on until the reactive power required by the system is distributed or all N modules need to output reactive power.
The specific implementation mode is as follows: when discriminant
When satisfied, only module k1Reactive power needs to be output, then the module k is at this time1Satisfies the following conditions:
at this time, the situation of the reactive power output by each module is as follows:
when discriminant
When satisfied, module k2Reactive power output is also required initially and module k needs to be guaranteed1、k2Is equal, then it needs to be satisfied that:
at this time, the situation of the reactive power output by each module is as follows:
by analogy, when the discriminant
When satisfied, module kx(x<N) also start to need reactive power output and module k needs to be guaranteed1、k2…kxIs equal, then it needs to be satisfied that:
at this time, the situation of the reactive power output by each module is as follows:
when the criterion (7) is satisfied, the module k is present1、k2…kN-1The output reactive power can not meet the requirement of the system, and the module kNReactive power needs to be output. In order to ensure the balance of the system, the apparent power of the N modules is also required to be ensured to be equal when distributing the reactive power, and the S is setref。SrefThe value of (c) can be obtained by equation (9), and the reactive power required to be output by each module can be obtained from the calculation result:
the invention can distribute the reactive power under the condition of ensuring the balance of each module of the system as much as possible when the system needs to inject the reactive power so as to eliminate the problems of overmodulation and the like.
Claims (2)
1. Reactive power distribution method suitable for problem of power imbalance among modules in photovoltaic power generationMethod, characterized in that the active power P emitted by each module is known for a photovoltaic power generation system using a cascade-type converterk1、Pk2…PkNAnd total reactive power Q of system required outputgUnder the condition of (1), the reactive power Q distributed to each modulekmCalculated according to the following formula:
wherein N is the number of modules cascaded in the system; sequencing the modules from small to large according to the active power sent by the modules, wherein the sequenced module is a module k1、k2…kNSatisfy active power Pk1≤Pk2≤…≤PkN;kmIndicating the kth in the systemmM is more than or equal to 1 and less than or equal to N, QkmRepresents its reactive power; pgRepresenting the total active power, V, output by the modules in the systemgRepresenting the grid voltage, VmaxIndicating the maximum voltage, S, allowed to be output by each moduleequIs determined by the following formula:
x is the number of modules which need to output reactive power when the power is not used; srefThe apparent power of the modules is the apparent power of the N modules at the moment; srefIs determined by the following formula:
wherein P isiRepresenting the active power of the ith module in the system.
2. The reactive power distribution method suitable for the problem of power imbalance among modules in photovoltaic power generation according to claim 1, wherein the reactive power distribution method specifically comprises:
1) when discriminant
When the system meets the requirement, the system does not need to perform reactive power control;
2) when discriminant
When satisfied, only module k1Reactive power needs to be output, then the module k is at this time1Satisfies the following conditions:
at this time, the situation of the reactive power output by each module is as follows:
when discriminant
When satisfied, module k2Reactive power output is also required initially and module k needs to be guaranteed1、k2Is equal, then it needs to be satisfied that:
at this time, the situation of the reactive power output by each module is as follows:
by analogy, when the discriminant
When satisfied, module kxAlso, there is an initial need to output reactive power, x<N, and the module k needs to be guaranteed1、k2…kxIs equal, then it needs to be satisfied that:
at this time, the situation of the reactive power output by each module is as follows:
3) when discriminant
When satisfied, module k at this time1、k2…kN-1The output reactive power can not meet the requirement of the system, and the module kNReactive power also needs to be output; at this time, in order to ensure the balance of the system, the apparent power of the N modules is ensured to be equal when distributing the reactive power, and the balance is ensured according to SrefThe value of (2) is used for solving the reactive power required to be output by each module:
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110620791.8A CN113315180B (en) | 2021-06-03 | 2021-06-03 | Reactive power distribution method suitable for problem of power imbalance among modules in photovoltaic power generation |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110620791.8A CN113315180B (en) | 2021-06-03 | 2021-06-03 | Reactive power distribution method suitable for problem of power imbalance among modules in photovoltaic power generation |
Publications (2)
Publication Number | Publication Date |
---|---|
CN113315180A CN113315180A (en) | 2021-08-27 |
CN113315180B true CN113315180B (en) | 2022-03-18 |
Family
ID=77377240
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202110620791.8A Active CN113315180B (en) | 2021-06-03 | 2021-06-03 | Reactive power distribution method suitable for problem of power imbalance among modules in photovoltaic power generation |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN113315180B (en) |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7230837B1 (en) * | 2006-03-27 | 2007-06-12 | North Carolina State University | Method and circuit for cascaded pulse width modulation |
CN105790302A (en) * | 2016-04-11 | 2016-07-20 | 阳光电源股份有限公司 | Cascade type photovoltaic grid-connected inverter and control method thereof and control device thereof |
CN108448589A (en) * | 2018-05-09 | 2018-08-24 | 国网上海市电力公司 | A kind of photovoltaic generating system low voltage crossing powerless control method |
CN109390962A (en) * | 2018-11-20 | 2019-02-26 | 浙江大学 | A kind of imbalance power adaptive optimization distribution method of the soft lineal system of multiterminal |
-
2021
- 2021-06-03 CN CN202110620791.8A patent/CN113315180B/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7230837B1 (en) * | 2006-03-27 | 2007-06-12 | North Carolina State University | Method and circuit for cascaded pulse width modulation |
CN105790302A (en) * | 2016-04-11 | 2016-07-20 | 阳光电源股份有限公司 | Cascade type photovoltaic grid-connected inverter and control method thereof and control device thereof |
CN108448589A (en) * | 2018-05-09 | 2018-08-24 | 国网上海市电力公司 | A kind of photovoltaic generating system low voltage crossing powerless control method |
CN109390962A (en) * | 2018-11-20 | 2019-02-26 | 浙江大学 | A kind of imbalance power adaptive optimization distribution method of the soft lineal system of multiterminal |
Non-Patent Citations (3)
Title |
---|
A Magnetic Integration Structure for the Buck-Cascaded Half-Bridge DC-DC Converter;Yi Chen;《2008 IEEE Power Electronics Spencialists Conference》;20080808;第264-268页 * |
Enhanced Active Power Balancing Capability of Grid-Connected Solar PV Fed Cascaded H-Bridge Converter;Rahul Sharma;《IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS》;20191231;第2281-2291页 * |
基于无功补偿的级联H桥光伏逆变器功率不平衡控制策略;赵涛;《中国电机工程学报》;20170905;第5076-5085页 * |
Also Published As
Publication number | Publication date |
---|---|
CN113315180A (en) | 2021-08-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN109842142B (en) | Hybrid three-terminal high-voltage direct-current power transmission system and direct-current fault rapid current limiting method thereof | |
CN108631357B (en) | Medium-high voltage energy conversion system | |
US9825470B2 (en) | Multi-source power converter | |
CN105281355A (en) | Multi-level power converter | |
CN109687499B (en) | Voltage balance control method for series connection converter valve of flexible direct current converter station | |
Foureaux et al. | Cascaded multilevel SST medium voltage converter for solar applications | |
EP2536018B1 (en) | DC-AC converter with a plurality of inverters connected in parallel, and method | |
CN113315180B (en) | Reactive power distribution method suitable for problem of power imbalance among modules in photovoltaic power generation | |
Ma et al. | A control scheme of three phase solid state transformer for PV generation based on improved voltage-tracking method of DC links | |
Feng et al. | Combined DC voltage control scheme for three-port energy router based on instantaneous energy balance | |
CN110970934B (en) | Grid-connected pre-synchronization control device for AC-DC bidirectional power converter in hybrid micro-grid | |
Vavilapalli et al. | A buck-chopper based energy storage system for the cascaded H-bridge inverters in PV applications | |
CN112994090B (en) | Photovoltaic medium-voltage cascade converter control method suitable for power imbalance among modules | |
CN106556762B (en) | Control method for aging test of cascaded high-voltage frequency converter | |
Yu et al. | A three-port input-series and output-parallel dc-dc converter with distributed control for medium-voltage dc distribution system | |
Liu et al. | Start-up scheme for dual-active-bridge based 10KV power electronics transformer in PV application | |
Wang et al. | A reactive power control optimization scheme for the power imbalance of cascaded photovoltaic converter | |
CN109361206B (en) | Energy control method of ship medium-voltage power grid structure based on multi-terminal DC-DC converter | |
Wang et al. | Electronic power transformer to secure the power supply of a mission critical microgrid | |
EP3424119B1 (en) | Fuel cell power plant with real and reactive power modes | |
Gorla et al. | Solid state transformer control aspects for various smart grid scenarios | |
CN111600335B (en) | Miniature intelligent power station circuit topological structure and energy management strategy thereof | |
Korhonen et al. | Feedforward control of isolating photovoltaic DC-DC converter to reduce grid-side DC link voltage fluctuation | |
Cao et al. | A Triple Active Bridge (TAB) Based Solid-State Transformer (SST) for DC Fast Charging Systems: Architecture and Control Strategy | |
Gao et al. | Multi-level cascaded medium frequency isolated power conversion system based on dual active bridge |
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 |