CN114268116A - State space modeling method of master-slave alternating-current micro-grid considering communication time delay - Google Patents
State space modeling method of master-slave alternating-current micro-grid considering communication time delay Download PDFInfo
- Publication number
- CN114268116A CN114268116A CN202111206841.4A CN202111206841A CN114268116A CN 114268116 A CN114268116 A CN 114268116A CN 202111206841 A CN202111206841 A CN 202111206841A CN 114268116 A CN114268116 A CN 114268116A
- Authority
- CN
- China
- Prior art keywords
- slave
- state space
- master
- current
- voltage
- 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
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention discloses a master-slave alternating current micro-grid state space modeling method considering communication time delay, which is characterized in that a master-slave control parallel alternating current micro-grid structure is formed by a plurality of energy storage converters. Aiming at the technical problem of communication delay existing when the host transmits a current instruction to the slave through low-bandwidth communication, the invention carries out modeling adjustment on system control parameters influencing the stability according to communication parameters of actual engineering, improves the stability of the system and further improves the productivity.
Description
Technical Field
The invention relates to the field of electric power, in particular to a stability analysis technology for a state space of a master-slave alternating-current micro-grid of communication delay in the field of electric power.
Background
In an independent alternating current micro-grid, the energy storage system can provide stable voltage and frequency for loads and other distributed power supplies, the stability and reliability of the micro-grid are enhanced, and the consumption level of renewable energy sources such as wind and light is improved. As a mainstream form of energy storage, electrochemical energy storage is mainly composed of a battery body, a battery management system, and a power conversion system. The parallel operation of the energy storage converters can effectively improve the reliability of the system, and the flexible configuration of the system capacity and the fine management of the battery units are realized. The master-slave control is used as a simple multi-machine parallel coordination control method, voltage with constant amplitude and frequency can be provided for a load, and the influence of line impedance on the steady-state power distribution among the converters is small. However, the number of the alternating current microgrid converters in a master-slave control mode is large, and multiple time scale coupling exists among all links of the control system, so that factors influencing the stability of the system are complex.
How to effectively and reasonably model the alternating-current microgrid in a master-slave control mode is the basis of stability analysis work. Based on effective and reasonable modeling, the influence of system parameters and control parameters on the stability of the master-slave alternating-current micro-grid under each time scale of the system is analyzed, and the key for improving the stability of the system is realized.
Around master-slave control, the master-slave architecture relies on low bandwidth communicationThe slave machine current instruction is issued, and interaction between low-bandwidth communication and a control system exists, so that the system stability is influenced. Such as the document [1 ]]Stability analysis in Lixia, Guo Li, Wang Chengshan, microgrid Master Slave control mode [ J]Electrotechnical journal, 2014, 29 (02): 24-34, establishing a discrete time state space model of the master-slave structure microgrid system, and discussing the influence of key control parameters, the number of power supplies and load change on the stability of the system; such as the document [2 ]]Liu Z.,Liu J.,Hou X.,et al.Output Impedance Modeling and Stability Prediction of Three-Phase Paralleled Inverters With Master-Slave Sharing Scheme Based on Terminal Characteristics of Individual Inverters[J]IEEE Transactions on Power Electronics,2016, 31(7): 5306-; such as document [3 ]]Mortezaei A.,
M.G., Savaghebi M.,et al.Cooperative Control of Multi-Master–Slave Islanded Microgrid With Power Quality Enhancement Based on Conservative Power Theory[J]IEEE Transactions on Smart Grid, 2018,9(4): 2964-; such as document [4 ]]Chen J.,Hou S.,Chen J.Seamless mode transfer control for master–slave microgrid[J]IET Power Electronics, 2019,12(12): 3158-; such as document [5 ]]Li D.,Man Ho C.N.,A Delay-Tolerable Master–Slave Current-Sharing Control Scheme for Parallel-Operated Interfacing Inverters with Low-Bandwidth Communication[J].IEEE Transactions on Industry Applications 2020, 56(2):1575-1586. an alternating current and direct current side multi-machine parallel system running around grid connection discusses the influence of communication time delay on system stability when the direct current load is equally divided by adopting master-slave control, and a method of current instruction low-pass filtering and direct current voltage feedforward is adopted in slave control to improve the stability margin of the system.
The research literature of the master-slave micro-grid takes less consideration of the influence of low-bandwidth communication delay on system stability, and a few researches take the influence into consideration, but a general modeling method is lacked in analysis, so that comprehensive and accurate stability analysis is difficult to perform.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to solve the problems that: the method is used for analyzing the stability of the independent alternating current micro-grid adopting a master-slave structure and assisting in system parameter design, thereby solving the problem of the stability of the system caused by communication delay.
Aiming at the problems, the invention provides a state space model of an independent alternating current micro-grid under a master-slave structure considering communication time delay, a zero-order retainer is adopted to model low-bandwidth communication time delay, second-order Pade approximation is carried out, and the dynamics of master-slave control, converter power and load are fully considered in the model.
A master-slave alternating current micro-grid state space modeling method considering communication time delay is characterized in that a master-slave control parallel alternating current micro-grid structure is formed by a plurality of energy storage converters, the direct current side of each energy storage converter is independently connected to a battery unit, the alternating current side of each energy storage converter is connected to a common coupling point through an LCL filter and supplies power to a load through an isolation transformer, and a voltage and current controller realizes coordinated starting, stopping and protection of the plurality of energy storage converters.
In the technical scheme, the method comprises the following steps: the method comprises the following steps: establishing a host state space model under a dq coordinate system, selecting an energy storage converter as a host, and establishing and maintaining the voltage and the frequency of the microgrid system by adopting constant voltage and constant frequency control through a central controller; step two: establishing a slave state space model under a dq coordinate system, taking the rest energy storage converters as slaves, obtaining the amplitude and the phase of the voltage of the microgrid through a phase-locked loop by a central controller, obtaining the output current of a host in real time through low-bandwidth communication as a reference, and performing current source type control to realize power sharing of the master and the slave; step three: establishing a load state space model under a dq coordinate system; step four: and establishing an independent alternating current microgrid state space model.
In the first step, a state space model of the host computer under a dq coordinate system is established. The state space model of the LCL filter is:
wherein u isinv_dqComponent of converter port voltage in dq axis, uPCC_dqIs the component of the PCC voltage on the dq axis.
In the first step, the state space model of the voltage current controller is:
wherein x isu_dqIntegrator output, x, representing the outer loop of the host dq-axis voltagei_dqThe integrator output represents the inner loop of the host dq-axis current.
In the first step, the host state space model of sampling and modulation delay is:
wherein T issThe switching period is expressed as a first-order lag element 1/(1.5T)s+1)。
In step one, a state variable x is selectedmaster＝[iL1_d,iL1_q,uC_d,uC_q,iL2_d,iL2_q,xu_d,xu_q,xi_d,xi_q, uinv_d,uinv_q]TInput variable umaster＝[uPCC_d,uPCC_q,ud_ref,uq_ref]The state space model of the host is:
in the second step, a state space model of the slave machine under the dq coordinate system is established, the LCL filter state space model is consistent with that of the master machine, a zero-order retainer is adopted to carry out low-bandwidth communication time delay, and second-order Pade approximation is carried out, wherein the method comprises the following steps:
wherein, TLBCAnd representing a low-bandwidth communication cycle, converting the transfer expression into a state space energy control standard model, and comprising the following steps:
wherein x isLBC、uLBCAnd yLBCState variables, input variables and output variables representing low bandwidth communication delays, respectively.
The input variable is the host L1Current iL1_dq_mThen the model is:
and (3) the state space of the slave machine current instruction low-pass filtering link is modeled as follows:
selecting a state variable xslave＝[iL1_d,iL1_q,uC_d,uC_q,iL2_d,iL2_q,xi_d_LBC_1,xi_q_LBC_1,xi_d_LBC_2, xi_q_LBC_2,id_ref,iq_ref,xi_d,xi_q,uinv_d,uinv_q]TInput variable uslave＝[uPCC_d,uPCC_q,iL1_d,iL1_q]Then, the state space model of the slave is:
in the third step, when the load is a resistive load, the load state space model of the PCC voltage is:
where n represents the number of slaves operating in parallel.
In the fourth step, the state space models of the host, the slave and the load are integrated, and the state space model under the condition of multi-machine parallel connection is as follows:
compared with the prior art, the invention has the following advantages: (1) a master-slave alternating-current microgrid state space modeling method considering communication time delay is provided, and communication delay existing when a master machine transmits a current instruction to a slave machine through low-bandwidth communication is considered. The method is beneficial to analyzing the influence of communication time delay on the stability of the micro-grid system, and is convenient for flexibly adjusting the system control parameters according to the communication parameters in the actual engineering so as to improve the stability of the system. (2) The model can be flexibly expanded according to the number of the actual energy storage converters, and is convenient for quick modeling when the system structure changes, so that the productivity is improved.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention, are not to be construed as unduly limiting the invention. The terminology in the drawings is for the purpose of describing and explaining the invention only and is not to be construed as any additional limitation.
FIG. 1 is a diagram of an AC microgrid junction in a master-slave configuration.
Fig. 2 is a master-slave control block diagram.
FIG. 3 is a first distribution diagram of system feature roots when parameters change.
FIG. 4 is a second distribution diagram of the system feature root during parameter variation.
FIG. 5 is a third distribution diagram of the system feature root when the parameters are changed.
FIG. 6 is a distribution diagram of the system feature root during parameter variation.
FIG. 7 is a fifth distribution diagram of system feature root during parameter variation.
Fig. 8 is a first experimental waveform diagram.
Fig. 9 is a second experimental waveform.
Detailed Description
The invention will be further described with reference to the accompanying drawings and specific embodiments so that the invention may be more clearly and intuitively understood.
Example (b): as shown in a master-slave structure alternating-current microgrid structure diagram in fig. 1, the invention relates to a state space modeling method of a master-slave alternating-current microgrid considering communication delay. The direct current side of each energy storage converter is independently connected to the battery unit, and the alternating current side of each energy storage converter is connected to a common coupling point through the LCL filter and supplies power to the load through the isolation transformer. Selecting a converter as a host, and adopting constant voltage and constant frequency control to establish and maintain the voltage and frequency of the system; and the other converters are used as slaves, the amplitude and the phase of the voltage of the microgrid are obtained through a phase-locked loop, and the output current of the host is obtained in real time through low-bandwidth communication to be used as a reference to realize current source type control, so that the aim of power sharing of the master and the slave is fulfilled. Although the master-slave control only needs data interaction between the master and the slave, in the actual micro-grid project, the voltage and current controller is an indispensable important link for realizing the coordinated starting, stopping and protection of a plurality of converters.
As shown in the master-slave control block diagram of fig. 2, where each variable is suffixed_mIndicating host-related variables, adding suffixes_sRepresenting slave dependent variables. The host being referenced u by a voltaged_refAnd uq_refAnd constant voltage and constant frequency control is realized. Wherein G isu_mFor the main machine voltage outer loop controller, proportional-integral control (k) is adoptedpu，kiu)；Gi_mFor the main machine current inner loop controller, PI control (k) is adoptedpi， kii). The slave computer obtains the d-axis component i of the actual output current by sampling the master computer through low bandwidth communicationL1_d_mAnd q-axis component iL1_q_mThrough a low-pass filtering step GLPF_i_refThen d-axis current reference i is obtained respectivelyd_ref_sAnd q-axis current reference iq_ref_sAnd further realize constant current control through the current loop. Gi_sFor slave current inner loop controller, PI control (k) is adoptedpi，kii)；GLPF_i_refThe method is a low-pass filtering link for the current instruction of the slave machine. i.e. iL1_dq_s(_m)Is L1Value of the current in dq coordinate system, iL2_dq_s(_m)Is L2Value of the current in dq coordinate system, edq_s(_m)For the values of the modulation reference in the dq coordinate system, eαβ_s(_m)For values of the modulation reference in the α β coordinate system, ω is the system angular frequency.
The method is used for further building an independent alternating current micro-grid state space model formed by three energy storage converters in parallel operation under a master-slave structure so as to verify the accuracy of the provided master-slave alternating current micro-grid state space modeling method. The reference data are shown in table 1 below. Table 1:
when analyzing the influence of each parameter on the system stability, the reference parameters are the parameters shown in table 1 except for special descriptions.
On the basis of the above, the system characteristic root distribution when each parameter changes is as follows, as shown in the first system characteristic root distribution diagram when the parameter changes in fig. 3, the outer ring scale factor k follows the host voltagepu_mFrom 0.1, by increasing steps 1 to 8, the characteristic values eig.1 and eig.2 are gradually shifted towards the imaginary axis,the damping ratio decreases.
As shown in the second distribution diagram of the system characteristic root when the parameters of FIG. 4 change, the inner ring proportionality coefficient k follows the current of the hostpi_mFrom 1, increasing by step 1 to 8, the characteristic values eig.1 and eig.2 gradually move towards the imaginary axis and the damping ratio decreases.
As shown in the third distribution diagram of the system characteristic root when the parameters of FIG. 5 change, the proportionality coefficient k of the inner ring along with the current of the slave machinepi_sIncreasing from 1 to 5 in steps of 1, the dominant feature roots eig.3 and eig.4 decrease in damping ratio.
As shown in the system characteristic root distribution diagram IV when the parameters of the figure 6 are changed, the time constant T is low-pass filtered according to the current instruction of the slave machineLPF_i_refChanging from 0.008s to 0.001s in steps of 0.001s, the characteristic values eig.5 and eig.6 damp the oscillation frequency increase and the damping ratio decreases.
As shown in the root distribution diagram of system characteristics when the parameters of fig. 7 are changed, the communication period T is changed along with the low bandwidthLBCWhen the characteristic value Eig.6 is shifted from 0.001s to 0.01s in steps of 0.001s, the damping ratio between the characteristic values Eig.7 and Eig.8 is decreased, and the damping oscillation frequency is increased and then decreased.
On the basis, three energy storage converter parallel operation systems adopting master-slave structures are built to verify the relevant conclusion of the master-slave structure multi-energy storage converter parallel system stability analysis, and the experimental result is as follows.
As shown in the experimental waveform diagram I of FIG. 8, a parameter T is set in the modelLPF_i_refIs 0.001, t1An active power load is put into the system at any moment, the output current between the master machine and the slave machine oscillates, the oscillation period is about 2ms, and the theoretical analysis is close to the theoretical analysis.
As shown in the experimental waveform chart II of FIG. 9, a parameter T is set in the modelLPF_i_ref＝0.01，t1The active power load is put into use at any moment and is 18kW, and the system stability is improved.
Also, the model provided by the above-mentioned embodiments can be flexibly expanded according to the number of the actual energy storage converters, so that the model can be quickly modeled when the system structure changes.
As described in the above embodiments, by fully considering the dynamic characteristics of the master-slave machine control, the converter power part and the load, and the dynamic characteristics of each time scale, the zero-order keeper is adopted to model the communication delay existing during the low-bandwidth communication transmission current instruction, and the control coefficient is flexibly adjusted according to the communication parameters in the actual engineering, so that the stability of the energy storage system is greatly improved, and the power consumption requirement of the user is ensured.
In addition to the above embodiments, the technical features of the present invention can be reselected and modified in steps to form new embodiments within the scope of the claims and the specification of the present invention, which can be realized by those skilled in the art without creative efforts, so that the embodiments of the present invention not described in detail should be regarded as specific embodiments of the present invention and are within the protection scope of the present invention.
Claims (9)
1. A master-slave alternating current micro-grid state space modeling method considering communication time delay is characterized in that a master-slave control parallel alternating current micro-grid structure is formed by a plurality of energy storage converters, the direct current side of each energy storage converter is independently connected to a battery unit, the alternating current side of each energy storage converter is connected to a common coupling point through an LCL filter and supplies power to a load through an isolation transformer, and a voltage and current controller realizes the coordinated starting, stopping and protection of the plurality of energy storage converters and comprises the following steps:
s1: establishing a host state space model under a dq coordinate system, selecting an energy storage converter as a host, and establishing and maintaining the voltage and the frequency of the microgrid system by adopting constant voltage and constant frequency control through a central controller;
s2: establishing a slave state space model under a dq coordinate system, taking the rest energy storage converters as slaves, obtaining the amplitude and the phase of the voltage of the microgrid through a phase-locked loop by a central controller, obtaining the output current of a host in real time through low-bandwidth communication as a reference, and performing current source type control to realize power sharing of the master and the slave;
s3: establishing a load state space model under a dq coordinate system;
s4: and establishing an independent alternating current microgrid state space model.
2. The method for modeling the state space of the master-slave alternating-current microgrid considering communication delay of claim 1, wherein the state space model of the LCL filter is as follows:
wherein u isinv_dqComponent of converter port voltage in dq axis, uPCC_dqIs the component of the PCC voltage on the dq axis.
3. The state space modeling method of the master-slave alternating current micro grid considering the communication delay as claimed in claim 2, wherein the state space model of the voltage current controller is:
wherein x isu_dqIntegrator output, x, representing the outer loop of the host dq-axis voltagei_dqThe integrator output represents the inner loop of the host dq-axis current.
4. The state space modeling method of the master-slave alternating current micro-grid considering the communication delay as claimed in claim 3, wherein the host state space model of the sampling and modulation delay is:
wherein T issThe switching period is expressed as a first-order lag element 1/(1.5T)s+1)。
5. The method as claimed in claim 4, wherein the method comprises a master-slave AC microgrid state space modeling method taking communication delay into accountIn that a state variable x is selectedmaster＝[iL1_d,iL1_q,uC_d,uC_q,iL2_d,iL2_q,xu_d,xu_q,xi_d,xi_q,uinv_d,uinv_q]TInput variable umaster＝[uPCC_d,uPCC_q,ud_ref,uq_ref]The state space model of the host is:
6. the state space modeling method of the master-slave alternating current micro-grid considering the communication delay as claimed in claim 2, wherein a zero-order keeper is adopted to perform low bandwidth communication delay, and a second-order Pade approximation is performed, as follows:
wherein, TLBCAnd representing a low-bandwidth communication cycle, converting the transfer expression into a state space energy control standard model, and comprising the following steps:
wherein x isLBC、uLBCAnd yLBCState variables, input variables and output variables representing low bandwidth communication delays, respectively.
7. The method for modeling the state space of the master-slave alternating-current micro-grid considering the communication delay as claimed in claim 6, wherein the input variable is the master L1Current iL1_dq_mThen the model is:
and (3) the state space of the slave machine current instruction low-pass filtering link is modeled as follows:
selecting a state variable xslave＝[iL1_d,iL1_q,uC_d,uC_q,iL2_d,iL2_q,xi_d_LBC_1,xi_q_LBC_1,xi_d_LBC_2,xi_q_LBC_2,id_ref,iq_ref,xi_d,xi_q,uinv_d,uinv_q]TInput variable uslave＝[uPCC_d,uPCC_q,iL1_d,iL1_q]Then, the state space model of the slave is:
8. the state space modeling method of the master-slave alternating current micro-grid considering the communication delay according to claim 1, wherein when the load is a resistive load, the load state space model of the PCC voltage is:
where n represents the number of slaves operating in parallel.
9. The state space modeling method of the master-slave alternating current micro-grid considering the communication delay as claimed in claim 1, wherein the state space model under the condition of multi-machine parallel connection is:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111206841.4A CN114268116B (en) | 2021-10-18 | 2021-10-18 | State space modeling method of master-slave alternating-current micro-grid considering communication time delay |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111206841.4A CN114268116B (en) | 2021-10-18 | 2021-10-18 | State space modeling method of master-slave alternating-current micro-grid considering communication time delay |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114268116A true CN114268116A (en) | 2022-04-01 |
| CN114268116B CN114268116B (en) | 2023-09-15 |
Family
ID=80824846
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111206841.4A Active CN114268116B (en) | 2021-10-18 | 2021-10-18 | State space modeling method of master-slave alternating-current micro-grid considering communication time delay |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114268116B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116388283A (en) * | 2023-06-06 | 2023-07-04 | 国网上海能源互联网研究院有限公司 | Off-grid parallel operation control method and device for multi-mobile energy storage system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150127425A1 (en) * | 2013-11-07 | 2015-05-07 | Palo Alto Research Center Incorporated | Strategic modeling for economic optimization of grid-tied energy assets |
| CN109327043A (en) * | 2018-10-24 | 2019-02-12 | 中国电力科学研究院有限公司 | A kind of voltage source converter grid-connected system inner loop control parsing transfer function modeling method and system |
| CN110165709A (en) * | 2019-07-01 | 2019-08-23 | 湖南大学 | Consider the virtual synchronous machine grid-connected inverting system stability method for improving of sampling time delay |
| CN110212575A (en) * | 2019-06-11 | 2019-09-06 | 贵州电网有限责任公司 | The small signal stability modal analysis method of double-fed blower one machine infinity bus system |
| WO2020186688A1 (en) * | 2019-03-20 | 2020-09-24 | 中车青岛四方车辆研究所有限公司 | Parallel control method and system for single-phase inverter, and inverter |
-
2021
- 2021-10-18 CN CN202111206841.4A patent/CN114268116B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150127425A1 (en) * | 2013-11-07 | 2015-05-07 | Palo Alto Research Center Incorporated | Strategic modeling for economic optimization of grid-tied energy assets |
| CN109327043A (en) * | 2018-10-24 | 2019-02-12 | 中国电力科学研究院有限公司 | A kind of voltage source converter grid-connected system inner loop control parsing transfer function modeling method and system |
| WO2020186688A1 (en) * | 2019-03-20 | 2020-09-24 | 中车青岛四方车辆研究所有限公司 | Parallel control method and system for single-phase inverter, and inverter |
| CN110212575A (en) * | 2019-06-11 | 2019-09-06 | 贵州电网有限责任公司 | The small signal stability modal analysis method of double-fed blower one machine infinity bus system |
| CN110165709A (en) * | 2019-07-01 | 2019-08-23 | 湖南大学 | Consider the virtual synchronous machine grid-connected inverting system stability method for improving of sampling time delay |
Non-Patent Citations (2)
| Title |
|---|
| 熊雄;孙庆凯;井天军;孙可;王坤;: "基于多分段P/f特性曲线的独立微电网协调控制策略", 电力建设, no. 04 * |
| 马添翼;金新民;黄杏;: "含多变流器的微电网建模与稳定性分析", 电力系统自动化, no. 06 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116388283A (en) * | 2023-06-06 | 2023-07-04 | 国网上海能源互联网研究院有限公司 | Off-grid parallel operation control method and device for multi-mobile energy storage system |
| CN116388283B (en) * | 2023-06-06 | 2023-08-04 | 国网上海能源互联网研究院有限公司 | Off-grid parallel operation control method and device for multi-mobile energy storage system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114268116B (en) | 2023-09-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108363306B (en) | Micro-grid distributed controller parameter determination method based on linear quadratic optimization | |
| Ziouani et al. | Hierarchical control for flexible microgrid based on three-phase voltage source inverters operated in parallel | |
| Lu et al. | SoC-based dynamic power sharing method with AC-bus voltage restoration for microgrid applications | |
| Shuai et al. | A maximum power loading factor (MPLF) control strategy for distributed secondary frequency regulation of islanded microgrid | |
| CN110011296B (en) | Direct-current micro-grid distributed droop control method based on active disturbance rejection control technology | |
| Lenka et al. | PV integrated multifunctional off-board EV charger with improved grid power quality | |
| Monesha et al. | Microgrid energy management and control: Technical review | |
| Zeng et al. | Hierarchical cooperative control strategy for battery storage system in islanded DC microgrid | |
| CN110137971B (en) | Voltage stability control method for three-phase alternating current power spring | |
| Liu et al. | Comprehensive control scheme for an interlinking converter in a hybrid AC/DC microgrid | |
| CN111817326A (en) | Distributed energy storage SOC control and integration method under alternating current micro-grid island mode | |
| Zhu et al. | Coordination control strategy for battery-ultracapacitor hybrid energy storage system in microgrids with unbalanced and nonlinear loads | |
| CN109888829A (en) | Photovoltaic microgrid system based on the sagging control of improvement perception is from grid-connected seamless switch-over system | |
| Li et al. | Analysis of multi-agent-based adaptive droop-controlled AC microgrids with PSCAD: modeling and simulation | |
| Prabaharan et al. | An overview of control techniques and technical challenge for inverters in micro grid | |
| CN103904654A (en) | Combined three-phase inverter circuit parallel operation control method | |
| CN115864520A (en) | Control method and system for accessing hybrid power grid based on high-proportion photovoltaic energy | |
| Malik et al. | Cost-based droop scheme for converters in interconnected hybrid microgrids | |
| CN117410963A (en) | Smooth switching control method for optical storage micro-grid system | |
| CN110797902A (en) | Improved master-slave control method for direct-current power distribution network | |
| CN114268116B (en) | State space modeling method of master-slave alternating-current micro-grid considering communication time delay | |
| CN110061504A (en) | A kind of slave power control method based on quasi- ratio resonance complex controll | |
| Wang et al. | A unified droop control of AC microgrids under different line impedances: Revisiting droop control and virtual impedance method | |
| Monesha et al. | Microgrid: recent trends and control | |
| CN116316912B (en) | Electric energy router power control method based on double-degree-of-freedom multi-constraint relation |
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 |