CN117335476A - SOC balance method, device and system for network-structured energy storage - Google Patents
SOC balance method, device and system for network-structured energy storage Download PDFInfo
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Classifications
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- 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
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
- H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
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- 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
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0047—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with monitoring or indicating devices or circuits
- H02J7/0048—Detection of remaining charge capacity or state of charge [SOC]
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
- H01M2010/4271—Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
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- 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
- H02J2203/20—Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
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Abstract
The invention relates to a SOC balance method, a device and a system for net-structured energy storage, wherein the method is applied to a net-structured energy storage system, the net-structured energy storage system comprises a plurality of net-structured converters and energy storage equipment connected with the net-structured converters, and the method comprises the following steps: acquiring the real-time SOC of each energy storage device, and calculating to acquire an average SOC; and generating an active power compensation signal for each grid-connected converter based on the difference value between the average SOC and the real-time SOC of the corresponding energy storage device, and controlling the output active power of the grid-connected converter based on the active power compensation signal. Compared with the prior art, the system and the method can realize SOC balance among multiple energy storage devices on the premise of not influencing the supporting capacity of the system power grid, and have the advantages of high reliability and the like.
Description
Technical Field
The invention belongs to the technical field of power electronics, and particularly relates to a SOC (state of charge) balancing method, device and system for network-structured energy storage.
Background
In the existing power system, the proportion of new energy sources such as wind power and photovoltaic power generation is continuously improved. However, these new energy sources are intermittent and unpredictable, and it is difficult to meet smooth supply of electric loads. At the same time, as the power load increases rapidly, the peak-to-valley difference in power demand becomes increasingly apparent. The energy storage converter can effectively buffer the intermittence of the new energy through storing and releasing the new energy, promote the large-scale grid connection of the new energy, realize the flat-top valley filling of the power load, and further improve the reliability and the flexibility of the power grid. In addition, early energy storage systems primarily employed grid-connected converters only for providing power output to the grid. However, as the proportion of the converter in the power grid increases, the requirement of the converter increases, and the converter needs to provide power grid support for the power grid in addition to power output. In order to meet the requirement, a grid-structured converter is provided, and the grid-structured converter realizes power output and active support of a power grid by simulating the port characteristics of a traditional synchronous machine.
The invention patent CN116316768B proposes a network-structured distributed energy storage system, comprising: the battery module, the network-structured power conversion module, the integrated energy storage management module and the medium-voltage transformer can prevent uneven inter-cluster voltage caused by inconsistent battery clusters by arranging the sub-power conversion units corresponding to the batteries one by one, automatically adjust power distribution of each battery cluster, fully utilize the flexibility of distributed energy storage under the condition of actively supporting a power grid, and realize the maximization of energy storage utilization of the batteries. This patent considers only the power balance between the power conversion units, and does not consider the influence of power distribution on the battery SOC. And too low an SOC of the energy storage device can reduce the lifetime of the energy storage device, affecting the efficiency of the system.
The invention patent CN115276069B discloses a virtual networking coordination control method and device of a large-scale energy storage power station. And the PCS of each battery pack in the energy storage system controls the frequency of the supporting power grid based on a Virtual Synchronous Generator (VSG), corrects virtual inertia parameters of each VSG unit based on the proposed control coefficient correction algorithm according to the SOC state of each battery pack of the energy storage system, and accordingly adjusts the power output of the energy storage unit. However, the control strategy modifies control parameters such as virtual inertia, so that inertia characteristics can be influenced, and the supporting capacity of the energy storage system to the power grid can be influenced.
In order to ensure good operation of the power grid, two requirements are set for an energy storage grid-connected system: firstly, the supporting capacity of the energy storage grid-connected system to the power grid can be improved by adopting a grid-structured converter; secondly, the SOC balance among a plurality of energy storage devices is realized, the service life of the energy storage devices can be reduced due to the fact that the SOC of the energy storage devices is too low, and the situation can be avoided due to the SOC balance. However, it is difficult to achieve both of these requirements with the current methods. The partial method ensures the power grid supporting capability of the energy storage grid-connected system, but does not consider SOC balance. The other part of the method ensures the SOC balance, but changes the power grid supporting capacity of the energy storage grid-connected system. Therefore, a new control method of the energy storage grid-connected system needs to be developed, and the SOC balance among multiple energy storage devices is realized on the premise of not affecting the supporting capacity of a system power grid.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide a high-reliability network-structured energy storage SOC balance method, device and system, which can realize SOC balance among multiple energy storage devices on the premise of not influencing the supporting capacity of a system power grid.
The aim of the invention can be achieved by the following technical scheme:
the SOC balance method for the grid-structured energy storage is applied to a grid-structured energy storage system, and the grid-structured energy storage system comprises a plurality of grid-structured converters and energy storage equipment connected with the grid-structured converters, and comprises the following steps:
acquiring the real-time SOC of each energy storage device, and calculating to acquire an average SOC;
and generating an active power compensation signal for each grid-connected converter based on the difference value between the average SOC and the real-time SOC of the corresponding energy storage device, and controlling the output active power of the grid-connected converter based on the active power compensation signal.
Further, the active power compensation signal is obtained based on a PI controller, a repetitive controller, or a model predictive controller.
Further, the calculation formula of the active power compensation signal is as follows:
wherein ΔP is an active power compensation signal, K p,SOC 、K i,SOC Proportional and integral coefficients, SOC, of the PI controller, respectively ave Is the average SOC, SOC i Is the real-time SOC of the ith energy storage device.
Further, the active power compensation signal of each of the grid-connected converters is independently generated.
Further, the controlling the output active power of the grid-structured converter specifically includes:
acquiring voltage and current information at a public connection point of the grid-connected transformer in real time, and calculating and obtaining corresponding real-time active power based on the voltage and current information;
generating a voltage phase control signal based on the real-time active power and the active power compensation signal;
and generating a control instruction based on the voltage phase control signal to control the output active power of the grid-connected converter.
Further, after the voltage and current information is collected, corresponding real-time reactive power is obtained through calculation based on the voltage and current information, a voltage amplitude control signal is generated, and a control instruction is generated based on the voltage amplitude control signal so as to control the output reactive power of the grid-built converter.
The invention also provides a SOC balance device for the network-structured energy storage, which is applied to the network-structured energy storage system, wherein the network-structured energy storage system comprises a plurality of network-structured converters and energy storage equipment connected with the network-structured converters, and comprises:
the acquisition processing module is connected with each energy storage device and used for acquiring the real-time SOC of the energy storage device and calculating to acquire an average SOC;
and the plurality of single-converter control modules are respectively and correspondingly connected with each grid-formed converter, are connected with the acquisition processing module, generate active power compensation signals based on the difference value of the average SOC and the real-time SOC of the corresponding energy storage equipment, and control the output active power of the corresponding grid-formed converter based on the active power compensation signals.
Further, the single converter control module includes:
the SOC balance control unit is used for generating the active power compensation signal;
and the network-structured control unit is used for generating a control instruction for controlling the output power of the corresponding network-structured converter through active power control and reactive power control, and performing compensation processing based on the active power compensation signal in the active power control.
Further, the active power compensation signal is obtained based on a PI controller, a repetitive controller, or a model predictive controller.
Further, the calculation formula of the active power compensation signal is as follows:
wherein ΔP is an active power compensation signal, K p,SOC 、K i,SOC Proportional and integral coefficients, SOC, of the PI controller, respectively ave Is the average SOC, SOC i And (3) the real-time SOC value of the energy storage equipment connected with the ith grid-connected converter.
Further, in the network configuration control unit, the active power control specifically includes:
acquiring voltage and current information at a public connection point of the grid-connected transformer in real time, and calculating and obtaining corresponding real-time active power based on the voltage and current information;
generating a voltage phase control signal based on the real-time active power and the active power compensation signal;
and generating a control instruction based on the voltage phase control signal so as to control the output power of the corresponding grid-connected converter.
Further, in the network-structured control unit, the reactive power control specifically includes:
and calculating and obtaining corresponding real-time reactive power based on the voltage and current information, generating a voltage amplitude control signal, and generating a control instruction based on the voltage amplitude control signal so as to control the output reactive power of the grid-structured converter.
The invention also provides a net-structured energy storage system, which comprises the SOC balance device for net-structured energy storage.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the invention, on the premise of ensuring the power grid supporting capability of the grid-structured converter, the active power compensation signal is generated according to the real-time SOC, and the parameters of grid-structured control are dynamically adjusted, so that the output power of the grid-structured converter is adjusted, SOC balance among a plurality of energy storage devices is realized, the condition that the SOC of part of the energy storage devices is too low is ensured not to occur, the service life of an energy storage system is prolonged, and the good operation of the system is ensured.
2. The control strategy of the invention does not modify the original control parameters, and ensures the same inertia characteristics.
3. The invention can independently control each network-structured converter, can be realized in the local control of each network-structured converter, and improves the reliability of the system.
Drawings
FIG. 1 is a schematic diagram of a grid-formation energy storage system according to the present invention;
FIG. 2 is a diagram of an SOC balance strategy architecture according to the present invention;
FIG. 3 is a schematic diagram of a DC-DC converter DC voltage controller;
FIG. 4 shows the results of the active power and SOC simulation for the same initial SOC under the control of the present invention, wherein (4 a) is the active power and (4 b) is the SOC;
fig. 5 shows the active power and SOC simulation results for different initial SOCs under the control of the present invention, where (5 a) is the active power and (5 b) is the SOC.
Detailed Description
The invention will now be described in detail with reference to the drawings and specific examples. The present embodiment is implemented on the premise of the technical scheme of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following examples.
Example 1
The embodiment provides an SOC balancing method for grid-formed energy storage, which is applied to a grid-formed energy storage system, as shown in fig. 1, and the grid-formed energy storage system includes a plurality of grid-formed converters and energy storage devices connected with the grid-formed converters, and the SOC balancing method includes the following steps: acquiring a real-time SOC value of energy storage equipment connected with each grid-connected converter, and calculating to obtain an average SOC; for a certain grid-type converter, an active power compensation signal is generated based on the difference value between the average SOC and the real-time SOC value of the grid-type converter, and the output active power of the corresponding grid-type converter is controlled based on the active power compensation signal. The SOC balance method can carry out SOC balance control on a plurality of energy storage grid-connected converters controlled by a grid structure, ensures that the SOC of part of energy storage equipment is not too low, prolongs the service life of an energy storage system, and ensures the good operation of the system.
In a specific embodiment, the active power compensation signal may be obtained based on a PI controller, a repetitive controller, a model predictive controller, or the like. The calculation formula of the active power compensation signal by adopting the PI controller in the embodiment is as follows:
wherein ΔP is an active power compensation signal, K p,SOC 、K i,SOC Proportional and integral coefficients, SOC, of the PI controller, respectively ave Is the average SOC, SOC i And (3) the real-time SOC value of the energy storage equipment connected with the ith grid-connected converter.
Through the PI controller, an active power compensation signal can be conveniently obtained, so that the output power of the grid-connected converters is further controlled, and the SOC balance among the grid-connected converters is ensured.
The effectiveness of the scheme is verified through the following two simulation experiments, a simulation platform is adopted to build a system simulation model, and the model comprises an energy storage battery, a grid-structured converter, line impedance, a large power grid model and the like.
Simulation experiment 1:
two network-structured converters are adopted, and control parameters of the two network-structured converters, such as virtual inertia, virtual damping and the like, are different. The two grid-connected converters are respectively connected with two groups of batteries, and the capacities of the two groups of batteries are the same.
The initial capacities of the two groups of batteries are the same, and the SOC balance strategy and the network construction control work normally. The output active power and SOC states of the two converters are shown in fig. 4. It can be seen that the output active power of the two grid-connected converters is significantly different in the start-up state, because the grid-connected control parameters of the two grid-connected converters are different. However, after entering a stable state, the SOC balance strategy enables the output active power of the two converters to be always the same. Because the capacities of the two sets of batteries are the same, all the same active power output keeps the SOC of the two sets of batteries the same all the time.
Simulation experiment 2:
two network-structured converters are adopted, and control parameters of the two network-structured converters, such as virtual inertia, virtual damping and the like, are different. The two grid-connected converters are respectively connected with two groups of batteries, and the capacities of the two groups of batteries are the same.
The initial capacities of the two groups of batteries are different, the network formation control always works, and the SOC balance strategy starts to work after 7 s. The output active power and SOC states of the two converters are shown in fig. 5. It can be seen that, because the grid control parameters of the two grid-connected converters are different, the output active power of the two grid-connected converters is obviously different before 7s, and the initial SOC of the two groups of batteries is different, so that the SOC of the two groups of batteries is always different. After 7s, the SOC balance strategy starts to work, and the output active power of the two converters changes, so that the corresponding SOCs of the two groups of batteries also change. It can be seen that the output active power of the two converters tends to be the same, while the SOC of the two sets of batteries also changes from different values to the same value.
The above-described method, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.
Example 2
The embodiment provides a network-structured energy storage SOC balancing device, which can be applied to a network-structured energy storage system as shown in fig. 1, wherein the network-structured energy storage system comprises a plurality of energy storage devices and corresponding network-structured converters. The energy storage device is connected to the grid-connected converter through a DC-DC converter, and the DC-DC converter is used for adjusting the direct current voltage of the grid-connected converter. The DC-DC converter is typically a BOOST converter. The topological structure of the grid-structured converter adopts a typical two-level topology, the filter structure adopts an LCL filter, the filter structure is connected with an alternating current power grid through a line, and the impedance of the line is not negligible.
Referring to fig. 2, the SOC balancing apparatus provided in this embodiment includes an acquisition processing module and a plurality of single-converter control modules, where the acquisition processing module is connected to an energy storage device connected to each grid-configured converter, and is configured to obtain a real-time SOC value of the energy storage device, and calculate to obtain an average SOC; the plurality of single converter control modules are respectively connected with each grid-formed converter correspondingly and are connected with the acquisition processing module, active power compensation signals are generated based on the difference value between the average SOC of the energy storage equipment and the real-time SOC value of the connected grid-formed converter, and the output active power of the corresponding grid-formed converter is controlled based on the active power compensation signals of the energy storage equipment. The single-converter control module independently controls one network-structured converter.
In a specific embodiment, as shown in fig. 2, the control modules of the single converters all adopt a control architecture of SOC balance+grid-formation control, wherein an SOC balance strategy is responsible for realizing SOC balance among the plurality of converters, and a grid-formation control strategy is responsible for realizing grid support. Specifically, the single converter control module comprises an SOC balance control unit and a grid-formed control unit, wherein the SOC balance control unit is used for generating the active power compensation signal; the grid-formation control unit is used for generating a control instruction for controlling the output power of the corresponding grid-formation converter through active power control and reactive power control, and in the active power control, compensation processing is performed based on the active power compensation signal.
In this embodiment, the network-structured control unit may implement active power control, reactive power control, and voltage control, where the active power control system is used to adjust the phase of the output voltage, and the reactive power control is used to adjust the amplitude of the output voltage. In general, active power control and reactive power control are as shown in (2) and (3).
V＝V 0 -K Q (Q g -Q 0 ) (3)
Wherein J and D p Is simulated inertia and stator damping, P 0 ，ω 0 ，Q 0 ，V 0 Which are respectively the reference values of the active power, frequency, reactive power and voltage amplitude.
A grid-formed converter has a plurality of different control parameters in the system, which control parameters affect the output power of the converter. The state of charge (SOC) of the energy storage device is dependent on the output active power of the grid-formed converter. Therefore, the SOC of the battery can be adjusted by only changing the output active power of the grid-type converter.
In order to improve the SOC balance of a plurality of network-structured converters without changing control parameters, the embodiment adds an SOC balance control unit on the basis of a network-structured control unit. Assuming that the number of grid-connected converters connected to the battery is n, each grid-connected converter adopts SOC balance control to keep the SOC of each battery the same. In this embodiment, the energy storage device is a battery, and all the network devices are configuredThe converters are mutually communicated through the acquisition and processing module to acquire the SOC information of all the batteries. The acquisition processing module is also used for calculating the average SOC (SOC) of all the batteries ave ) And SOC is taken ave To all of the grid-connected converters. To achieve SOC balance, the SOC of a single networked converter should be equal to the average SOC. Under the condition, the embodiment obtains an active power compensation signal through the PI controller to realize SOC balance control, thereby realizing zero static error, wherein the expression of the active power compensation signal is as follows:
wherein K is p,SOC 、K i,SOC The proportional and integral coefficients of the PI controller, respectively.
The output delta P of the PI controller is used as compensation to be sent to the active power control of the network-structured control unit, and the active power control scheme with compensation is rewritten as follows:
wherein Δp is the power-given compensation signal calculated by the SOC balance strategy.
In this embodiment, as shown in fig. 3, the control system of the DC-DC converter is used to regulate the output voltage of the DC-DC converter, i.e., the DC voltage of the grid-connected converter. A proportional-integral (PI) controller is employed to achieve zero steady-state error. The computational expression is:
wherein V is dc，ref Given as DC voltage, V dc For the actual DC voltage value, K p，dc 、K i，dc The proportional and integral coefficients of the PI controller, respectively.
Example 3
The embodiment provides a grid-type energy storage system, which comprises a plurality of grid-type converters, energy storage devices connected with the grid-type converters and the SOC balance device for grid-type energy storage as described in embodiment 2, wherein the SOC balance device is correspondingly arranged with each grid-type converter and each energy storage device, and each grid-type converter is independently controlled to realize SOC balance among all the energy storage devices of the whole grid-type energy storage system.
The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.
Claims (13)
1. The SOC balance method for the grid-structured energy storage is applied to a grid-structured energy storage system, and the grid-structured energy storage system comprises a plurality of grid-structured converters and energy storage equipment connected with the grid-structured converters, and is characterized by comprising the following steps:
acquiring the real-time SOC of each energy storage device, and calculating to acquire an average SOC;
and generating an active power compensation signal for each grid-connected converter based on the difference value between the average SOC and the real-time SOC of the corresponding energy storage device, and controlling the output active power of the grid-connected converter based on the active power compensation signal.
2. The method of claim 1, wherein the active power compensation signal is obtained based on a PI controller, a repetitive controller, or a model predictive controller.
3. The method of SOC balancing of a net-structured energy storage of claim 2, wherein the active power compensation signal has a calculation formula:
wherein ΔP is an active power compensation signal, K p,SOC 、K i,SOC Proportional and integral coefficients, SOC, of the PI controller, respectively ave Is the average SOC, SOC i Is the real-time SOC of the ith energy storage device.
4. The method of claim 1, wherein the active power compensation signal of each of the grid-connected inverters is generated independently.
5. The method for SOC balancing of a grid-tied energy storage according to claim 1, wherein the controlling the output active power of the grid-tied converter specifically comprises:
acquiring voltage and current information at a public connection point of the grid-connected transformer in real time, and calculating and obtaining corresponding real-time active power based on the voltage and current information;
generating a voltage phase control signal based on the real-time active power and the active power compensation signal;
and generating a control instruction based on the voltage phase control signal to control the output active power of the grid-connected converter.
6. The method of claim 5, further comprising calculating the voltage and current information to obtain a real-time reactive power based on the voltage and current information after the voltage and current information is collected, generating a voltage amplitude control signal, and generating a control command based on the voltage amplitude control signal to control the output reactive power of the grid-connected converter.
7. The utility model provides a network-structured type energy storage's SOC balancing unit is applied to network-structured type energy storage system, this network-structured type energy storage system includes a plurality of network-structured converters and the energy storage equipment who links to each other rather than, its characterized in that includes:
the acquisition processing module is connected with each energy storage device and used for acquiring the real-time SOC of the energy storage device and calculating to acquire an average SOC;
and the plurality of single-converter control modules are respectively and correspondingly connected with each grid-formed converter, are connected with the acquisition processing module, generate active power compensation signals based on the difference value of the average SOC and the real-time SOC of the corresponding energy storage equipment, and control the output active power of the corresponding grid-formed converter based on the active power compensation signals.
8. The network-structured energy storage SOC balancing apparatus of claim 7, wherein the single converter control module comprises:
the SOC balance control unit is used for generating the active power compensation signal;
and the network-structured control unit is used for generating a control instruction for controlling the output power of the corresponding network-structured converter through active power control and reactive power control, and performing compensation processing based on the active power compensation signal in the active power control.
9. The network-structured energy storage SOC balancing apparatus of claim 7 or 8, wherein the active power compensation signal is obtained based on a PI controller, a repetitive controller, or a model predictive controller.
10. The network-structured energy-storage SOC balancing apparatus of claim 9, wherein the active power compensation signal has a calculation formula:
wherein ΔP is an active power compensation signal, K p,SOC 、K i,SOC Proportional and integral coefficients, SOC, of the PI controller, respectively ave Is the average SOC, SOC i And (3) the real-time SOC value of the energy storage equipment connected with the ith grid-connected converter.
11. The network-structured energy storage SOC balancing apparatus of claim 8, wherein in the network-structured control unit, the active power control specifically includes:
acquiring voltage and current information at a public connection point of the grid-connected transformer in real time, and calculating and obtaining corresponding real-time active power based on the voltage and current information;
generating a voltage phase control signal based on the real-time active power and the active power compensation signal;
and generating a control instruction based on the voltage phase control signal so as to control the output power of the corresponding grid-connected converter.
12. The network-structured energy storage SOC balancing apparatus according to claim 11, wherein in the network-structured control unit, the reactive power control specifically includes:
and calculating and obtaining corresponding real-time reactive power based on the voltage and current information, generating a voltage amplitude control signal, and generating a control instruction based on the voltage amplitude control signal so as to control the output reactive power of the grid-structured converter.
13. A grid-type energy storage system comprising a SOC balancing device of the grid-type energy storage of any of claims 7-12.
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| CN118017576A (en) * | 2024-04-09 | 2024-05-10 | 江苏谷峰电力科技股份有限公司 | Net-structured string-type energy storage converter |
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2023
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118017576A (en) * | 2024-04-09 | 2024-05-10 | 江苏谷峰电力科技股份有限公司 | Net-structured string-type energy storage converter |
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