A distributed modular energy storage device

Abstract

The present invention relates to the field of energy storage technology, and discloses a distributed modular energy storage device, including: multiple energy storage modules, wherein the energy storage modules include multiple energy storage converters for accessing a power grid, and each energy storage converter is electrically connected to an energy storage unit; a regulating module, which is used to regulate the total output power of all energy storage modules connected to the power grid according to the power required by the power grid, and obtain the regulated total output power; a monitoring module, which is used to monitor the multiple energy storage modules in real time, and determine whether all energy storage modules connected to the power grid meet the set conditions, and obtain monitoring results; a control module, which is used to adjust the energy storage modules connected to the power grid according to the monitoring results obtained by the monitoring module. It is possible to realize adaptive adjustment of the energy storage modules according to the power required by the power grid, and ensure that the required power is provided to the power grid while balancing the work of each energy storage module.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology, and more specifically, to a distributed modular energy storage device. Background Art

[0002] Distributed energy storage devices refer to energy storage devices that are installed in various locations, usually close to power sources. They can convert electrical energy into chemical energy, mechanical energy, internal energy and other forms of energy and store them, and release them when needed to meet energy needs. Distributed energy storage has flexible access locations and mainly connects medium and low voltage distribution networks, microgrids and users' excess electricity to the power supply network.

[0003] In the prior art, in order to meet the needs of the power grid, since there are different power demands in different time periods, in most cases the output power of the energy storage device is adjusted according to the power consumption in the time period. If the number of energy storage units connected to the power grid is not adjusted, it will undoubtedly waste power and reduce the life of the energy storage unit. Therefore, it is necessary to balance the power required by the power grid and the actual working state of the energy storage unit. Therefore, it is necessary to propose a distributed modular energy storage device to at least partially solve the problems existing in the prior art. Summary of the invention

[0004] A series of simplified concepts are introduced in the Summary of the Invention, which will be further described in detail in the Detailed Description of the Invention. The Summary of the Invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0005] In order to at least partially solve the above problems, the present invention provides a distributed modular energy storage device, comprising:

[0006] A plurality of energy storage modules, each of which comprises a plurality of energy storage converters for accessing a power grid, each of which is electrically connected to an energy storage unit;

[0007] A regulating module, used to regulate the total output power of all energy storage modules connected to the grid according to the power required by the grid, to obtain the regulated total output power;

[0008] A monitoring module is used to monitor multiple energy storage modules in real time, determine whether all energy storage modules connected to the power grid meet the set conditions, and obtain monitoring results;

[0009] The control module is used to adjust the energy storage module connected to the power grid according to the monitoring results obtained by the monitoring module.

[0010] Preferably, the adjustment module includes:

[0011] A first acquisition unit, used to acquire a current difference between the power required by the power grid and the total output power of all energy storage modules connected to the power grid within a set time;

[0012] The analysis unit compares the current difference with a preset range to obtain a comparison result, and determines the total power deviation value of all energy storage modules connected to the power grid according to the comparison result;

[0013] The regulating unit regulates the total output power of all energy storage modules connected to the power grid according to the total power deviation value to obtain the regulated total output power.

[0014] Preferably, the analysis unit comprises:

[0015] A comparison subunit, used to compare the current difference value with a preset range to obtain a comparison result;

[0016] The first analysis subunit obtains the total power deviation value of all energy storage modules connected to the power grid according to the current difference if the comparison result is that the current difference exceeds the preset range;

[0017] The total power deviation value is obtained by the following formula:

[0018]

[0019] Where E is the total power deviation value, P D (t) is the power required by the power grid at any time t, P Z (t) is the total output power of all energy storage modules connected to the power grid obtained at any time t, t1 is the first arbitrary time, t2 is the second arbitrary time, and t2>t1;

[0020] The second analysis subunit, if the comparison result is that the current difference is within a preset range, then the total power deviation value of all energy storage modules connected to the power grid is zero.

[0021] Preferably, the monitoring module comprises:

[0022] A collection unit, used to obtain the adjusted total output power of all energy storage modules connected to the power grid and the total remaining capacity of all corresponding energy storage units at the collection time;

[0023] The calculation unit obtains the total remaining working time of all energy storage modules connected to the power grid at the collection time according to the adjusted total output power and the corresponding total remaining capacity obtained by the collection unit at the collection time;

[0024] The total remaining working time is obtained by the following formula:

[0025]

[0026] Among them, Ts is the total remaining working time, Q zs is the total remaining capacity, ΔT is the time interval for collection, P Z ′ (T) is the adjusted total output power obtained at the acquisition time T, T C Any collection time;

[0027] A judgment unit, for judging whether the total remaining working time obtained by the calculation unit at the collection time satisfies a set condition;

[0028] The result output unit outputs the monitoring result that, if the total remaining working time meets the set conditions, all energy storage modules connected to the power grid can continue to work; if the total remaining working time does not meet the set conditions, the monitoring result output is that the number of energy storage modules connected to the power grid needs to be increased.

[0029] Preferably, the setting condition is that the total remaining working time of the energy storage module is greater than the preset working time.

[0030] Preferably, the preset working time is m times the set remaining working time, and the value range of m is: m is greater than 0 and less than or equal to 1.

[0031] Preferably, the control module comprises:

[0032] A second acquisition unit, when the monitoring result of the monitoring module indicates that the number of energy storage modules connected to the power grid needs to be adjusted, acquires the power required by the power grid, the remaining capacity of each energy storage unit and the corresponding working status;

[0033] Determine the unit, and determine the number of energy storage modules connected to the grid based on the power required by the grid and the working status of each energy storage unit;

[0034] The control unit controls a corresponding number of energy storage modules to connect to the power grid according to the remaining capacity of each energy storage unit.

[0035] Preferably, the determining unit includes:

[0036] A first determination subunit determines, according to the working state of each energy storage unit, a set remaining capacity range corresponding to its optimal working state;

[0037] The second determination subunit determines the number of energy storage modules connected to the power grid according to the set remaining capacity range of each energy storage unit and the power required by the power grid.

[0038] Preferably, the working state includes: a charging working state and a discharging working state.

[0039] The working state represents the relationship between the remaining capacity of the energy storage unit and the charging efficiency and discharging efficiency under different charging and discharging voltages.

[0040] Preferably, the number of energy storage modules connected to the power grid is: the ratio of the power required by the power grid to the power of the energy storage modules when operating at maximum efficiency.

[0041] Compared with the prior art, the present invention has at least the following beneficial effects:

[0042] The distributed modular energy storage device of the present invention can realize adaptive adjustment of the energy storage module according to the power required by the power grid, ensuring that the required power is provided to the power grid while balancing the work of each energy storage module;

[0043] The distributed modular energy storage device described in the present invention can adjust the energy storage modules. After the adjustment, the total remaining working time of all energy storage modules connected to the power grid meets the set conditions, and all energy storage modules can discharge efficiently, thereby improving the discharge efficiency, saving electric energy, and balancing the power required by the power grid with the total output power of all energy storage modules connected to the power grid.

[0044] The distributed modular energy storage device described in the present invention, other advantages, objectives and features of the present invention will be reflected in part through the following description, and in part will be understood by technicians in this field through research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0046] Figure 1 A block diagram of the distributed modular energy storage device of the present invention;

[0047] Figure 2 A block diagram of a regulating module in a distributed modular energy storage device according to the present invention;

[0048] Figure 3 A block diagram of an analysis unit in a distributed modular energy storage device according to the present invention;

[0049] Figure 4 A block diagram of a monitoring module in a distributed modular energy storage device according to the present invention;

[0050] Figure 5 A block diagram of a control module in the distributed modular energy storage device of the present invention;

[0051] Figure 6 A block diagram of a determination unit in the distributed modular energy storage device described in the present invention. DETAILED DESCRIPTION

[0052] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments so that those skilled in the art can implement the invention with reference to the description.

[0053] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0054] like Figure 1 As shown, the present invention provides a distributed modular energy storage device, comprising:

[0055] A plurality of energy storage modules, each of which comprises a plurality of energy storage converters for accessing a power grid, each of which is electrically connected to an energy storage unit;

[0056] A regulating module, used to regulate the total output power of all energy storage modules connected to the grid according to the power required by the grid, to obtain the regulated total output power;

[0057] A monitoring module is used to monitor multiple energy storage modules in real time, determine whether all energy storage modules connected to the power grid meet the set conditions, and obtain monitoring results;

[0058] The control module is used to adjust the energy storage module connected to the power grid according to the monitoring results obtained by the monitoring module.

[0059] The present invention sets the energy storage device in a modular way, so that each energy storage unit is equipped with an energy storage converter and connected to the power grid through the energy storage converter; the number of energy storage modules connected to the power grid can be set according to the power required by the power grid, and not all energy storage modules need to participate in power output;

[0060] Since the power required by the grid will fluctuate when supplying power to the grid, the adjustment module can adjust the total output power of all energy storage modules connected to the grid according to the power required by the grid to ensure the stability of providing the power required by the grid; and the monitoring module can monitor the working conditions of multiple energy storage modules in real time to determine whether all energy storage modules connected to the grid meet the set conditions, thereby obtaining the monitoring results, and then the control module can adjust the energy storage modules connected to the grid according to the monitoring results. The adjustment can be only a quantitative adjustment, or it can be an adjustment of the energy storage modules switching in and out of the grid; the energy storage modules can be adaptively adjusted according to the power required by the grid to ensure that the required power is provided to the grid while balancing the work of each energy storage module.

[0061] like Figure 2 As shown, in one embodiment, the adjustment module includes:

[0062] A first acquisition unit, used to acquire a current difference between the power required by the power grid and the total output power of all energy storage modules connected to the power grid within a set time;

[0063] The analysis unit compares the current difference with a preset range to obtain a comparison result, and determines the total power deviation value of all energy storage modules connected to the power grid according to the comparison result;

[0064] The regulating unit regulates the total output power of all energy storage modules connected to the power grid according to the total power deviation value to obtain the regulated total output power.

[0065] The current difference can be positive (the power required by the grid is greater than the total output power of all energy storage modules connected to the grid) or negative (the power required by the grid is less than the total output power of all energy storage modules connected to the grid). The preset range can be set to (-A, A), where A is a positive number.

[0066] In order to ensure that all energy storage modules connected to the grid can stably provide the required power to the grid, the power required by the grid and the total output power of all energy storage modules connected to the grid are obtained in real time, and the current difference between the two is obtained; then the current difference is analyzed to determine the total power deviation value of all energy storage modules connected to the grid. The total output power can be adjusted according to the total power deviation value to ensure the stability of providing the required power to the grid.

[0067] like Figure 3 As shown, further, the analysis unit includes:

[0068] A comparison subunit, used to compare the current difference value with a preset range to obtain a comparison result;

[0069] The comparison results include: the current difference value exceeds the preset range, and the current difference value is within the preset range;

[0070] The first analysis subunit obtains the total power deviation value of all energy storage modules connected to the power grid according to the current difference if the comparison result is that the current difference exceeds the preset range;

[0071] The total power deviation value is obtained by the following formula:

[0072]

[0073] Where E is the total power deviation value, P D (t) is the power required by the power grid at any time t, P Z (t) is the total output power of all energy storage modules connected to the power grid obtained at any time t, t1 is the first arbitrary time, t2 is the second arbitrary time, t2>t1; t1 and t2 can be the start time and end time of the set time;

[0074] The second analysis subunit, if the comparison result is that the current difference is within a preset range, then the total power deviation value of all energy storage modules connected to the power grid is zero.

[0075] When the current difference is within the preset range, it indicates that the total output power and the power required by the grid have reached a balanced state. At this time, there is no need to adjust the total output power of all energy storage modules connected to the grid, so the total power deviation value is recorded as zero; when the current difference exceeds the preset range, it indicates that the total output power and the power required by the grid are in an unbalanced state, which may easily cause unstable power supply or waste of electric energy in the grid, and the total output power needs to be adjusted through the total power deviation value. The specific adjustment can be achieved by adjusting the output power of the energy storage module or reducing the number of energy storage modules.

[0076] Through the above scheme, the total output power of the energy storage module can be effectively adjusted by combining the power required by the power grid and the total output power of the energy storage module to ensure that the total output power is balanced with the power required by the power grid, while preventing the waste of electric energy caused by the total output power being greater than the power required by the power grid.

[0077] like Figure 4 As shown, in one embodiment, the monitoring module includes:

[0078] A collection unit, used to obtain the adjusted total output power of all energy storage modules connected to the power grid and the total remaining capacity of all corresponding energy storage units at the collection time;

[0079] The calculation unit obtains the total remaining working time of all energy storage modules connected to the power grid at the collection time according to the adjusted total output power and the corresponding total remaining capacity obtained by the collection unit at the collection time;

[0080] The total remaining working time is obtained by the following formula:

[0081]

[0082] Among them, T s is the total remaining working time, Q zs is the total remaining capacity, ΔT is the time interval for collection (the time interval for calculating the total remaining working time), P Z ′ (T) is the adjusted total output power obtained at the acquisition time T, T C Any collection time;

[0083] A judgment unit, for judging whether the total remaining working time obtained by the calculation unit at the collection time satisfies a set condition;

[0084] The result output unit outputs the monitoring result that, if the total remaining working time meets the set conditions, all energy storage modules connected to the power grid can continue to work;

[0085] It shows that the total output power after adjustment by the adjustment module can provide the power required by the grid, and there is no need to adjust the number of energy storage modules in a short time;

[0086] If the total remaining working time does not meet the set conditions, the monitoring result output is: the number of energy storage modules connected to the grid needs to be increased;

[0087] This indicates that the total output power after adjustment by the adjustment module has a risk of power supply duration, and the number of energy storage modules connected to the grid needs to be increased.

[0088] Furthermore, the setting condition is that the total remaining working time of the energy storage module is greater than the preset working time.

[0089] Furthermore, the preset working time is m times the set remaining working time, and the value range of m is: m is greater than 0 and less than or equal to 1; the value of m can be set according to actual conditions so that the preset working time is greater than ΔT.

[0090] Since the power required by the power grid in each time period is different, the number of energy storage modules connected to the power grid is different. In order to ensure the accuracy of the regulation module in regulating the total output power of all energy storage modules, the regulated total output power and the corresponding total remaining capacity are monitored by the monitoring module, and the total remaining working time of all energy storage modules connected to the power grid is obtained. The total remaining working time is calculated with the power consumption within ΔT time as the collection time interval. The above calculation method can reduce the calculation error, improve the calculation accuracy of the total remaining working time, and make the judgment of the total remaining working time more accurate.

[0091] like Figure 5 As shown, in one embodiment, the control module includes:

[0092] The second acquisition unit acquires the power required by the power grid, the remaining capacity of each energy storage unit (including the remaining capacity of each energy storage unit connected to the power grid and the remaining capacity of each energy storage unit not connected to the power grid), and the corresponding working state (including the working state of each energy storage unit connected to the power grid and the working state of each energy storage unit not connected to the power grid) when the monitoring result of the monitoring module indicates that the number of energy storage modules connected to the power grid needs to be adjusted (here mainly refers to when the number of energy storage modules needs to be increased);

[0093] Determine the unit, and determine the number of energy storage modules connected to the grid based on the power required by the grid and the working status of each energy storage unit;

[0094] A control unit controls a corresponding number of energy storage modules to be connected to the power grid according to the remaining capacity of each energy storage unit;

[0095] Wherein, the working state includes: charging working state and discharging working state; here it refers to the discharging working state;

[0096] The working state indicates the relationship between the remaining capacity of the energy storage unit and the charging efficiency and the discharging efficiency under different charging and discharging voltages, and here it mainly indicates the relationship between the remaining capacity of the energy storage unit and the discharging efficiency under different discharging voltages.

[0097] When the monitoring result of the monitoring module is that the number of energy storage modules connected to the power grid needs to be adjusted, it indicates that the number of energy storage modules currently connected to the power grid and the total remaining capacity cannot support the power required by the power grid for a long time. In order to reduce the number of adjustments to the number of energy storage modules and improve the utilization rate of the energy storage units, through the above scheme, the number of energy storage modules connected to the power grid can be determined according to the working state of each energy storage unit and the corresponding remaining capacity, so as to improve the utilization efficiency of the energy storage units and save the use of electric energy. This is because the discharge efficiency of the energy storage unit varies under different remaining capacities. Generally, when the remaining capacity is about half of the total capacity, the discharge efficiency is the highest and the utilization efficiency of electric energy is the best. Therefore, the working states of multiple energy storage units can be selected to determine the number of energy storage modules connected to the power grid.

[0098] like Figure 6 As shown, further, the determining unit includes:

[0099] A first determination subunit determines, according to the working state of each energy storage unit, a set remaining capacity range corresponding to its optimal working state;

[0100] The second determination subunit determines the number of energy storage modules connected to the power grid according to the set remaining capacity range of each energy storage unit and the power required by the power grid.

[0101] Furthermore, the number of energy storage modules connected to the grid is: the ratio of the power required by the grid to the power of the energy storage modules when they are working in an optimal working state.

[0102] The optimal working state is when the charging efficiency or discharging efficiency of each energy storage unit is the maximum, and the corresponding remaining capacity at this time forms a set remaining capacity range. Therefore, according to the set remaining capacity range corresponding to the optimal working state of each energy storage unit and the current remaining capacity of this energy storage unit, multiple energy storage units can be screened (including each energy storage unit connected to the power grid and each energy storage unit not connected to the power grid), and the energy storage units that meet the optimal working state are screened out, and then sorted from large to small according to the remaining capacity;

[0103] Then, the number of energy storage modules connected to the grid is determined first. Assuming that the number of energy storage modules that need to be connected to the grid is n, and the number of energy storage units that can work in the optimal working state is N (N is greater than n), the N energy storage units are sorted from large to small according to the remaining capacity, and then the energy storage modules corresponding to the first n energy storage units are selected from the N to be connected to the grid (of course, these n energy storage modules may include energy storage modules that have been connected to the grid and energy storage modules that have not been connected to the grid), so as to adjust the energy storage modules. After the adjustment, the total remaining working time of all energy storage modules connected to the grid meets the set conditions, and all energy storage modules can discharge efficiently, thereby improving the discharge efficiency, saving electric energy, and balancing the power required by the grid with the total output power of all energy storage modules connected to the grid.

[0104] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A distributed modular energy storage device, characterized in that: include: A plurality of energy storage modules, each of which comprises a plurality of energy storage converters for accessing a power grid, each of which is electrically connected to an energy storage unit; A regulating module, used to regulate the total output power of all energy storage modules connected to the grid according to the power required by the grid, to obtain the regulated total output power; A monitoring module is used to monitor multiple energy storage modules in real time, determine whether all energy storage modules connected to the power grid meet the set conditions, and obtain monitoring results; A control module, used to adjust the energy storage module connected to the power grid according to the monitoring results obtained by the monitoring module; The adjustment module comprises: A first acquisition unit, used to acquire a current difference between the power required by the power grid and the total output power of all energy storage modules connected to the power grid within a set time; The analysis unit compares the current difference with a preset range to obtain a comparison result, and determines the total power deviation value of all energy storage modules connected to the power grid according to the comparison result; The regulating unit regulates the total output power of all energy storage modules connected to the power grid according to the total power deviation value to obtain the regulated total output power; The analysis unit comprises: A comparison subunit, used to compare the current difference value with a preset range to obtain a comparison result; The first analysis subunit obtains the total power deviation value of all energy storage modules connected to the power grid according to the current difference if the comparison result is that the current difference exceeds the preset range; The total power deviation value is obtained by the following formula: Where E is the total power deviation value, P D (t) is the power required by the power grid at any time t, P Z (t) is the total output power of all energy storage modules connected to the power grid obtained at any time t, t1 is the first arbitrary time, t2 is the second arbitrary time, and t2>t1; The second analysis subunit, if the comparison result is that the current difference is within a preset range, then the total power deviation value of all energy storage modules connected to the power grid is zero; The monitoring module comprises: A collection unit, used to obtain the adjusted total output power of all energy storage modules connected to the power grid and the total remaining capacity of all corresponding energy storage units at the collection time; The calculation unit obtains the total remaining working time of all energy storage modules connected to the power grid at the collection time according to the adjusted total output power and the corresponding total remaining capacity obtained by the collection unit at the collection time; The total remaining working time is obtained by the following formula: Among them, T s is the total remaining working time, Q zs is the total remaining capacity, ΔT is the time interval for collection (the time interval for calculating the total remaining working time), P Z ′ (T) is the adjusted total output power obtained at the acquisition time T, T C Any collection time; A judgment unit, for judging whether the total remaining working time obtained by the calculation unit at the collection time satisfies a set condition; The result output unit outputs the monitoring result that, if the total remaining working time meets the set conditions, all energy storage modules connected to the power grid can continue to work; if the total remaining working time does not meet the set conditions, the monitoring result output is that the number of energy storage modules connected to the power grid needs to be increased.

2. The distributed modular energy storage device according to claim 1, characterized in that: The setting condition is: the total remaining working time of the energy storage module is greater than the preset working time.

3. The distributed modular energy storage device according to claim 2, characterized in that: The preset working time is m times the set remaining working time, and the value range of m is: m is greater than 0 and less than or equal to 1.

4. The distributed modular energy storage device according to claim 1, characterized in that: The control module comprises: A second acquisition unit, when the monitoring result of the monitoring module indicates that the number of energy storage modules connected to the power grid needs to be adjusted, acquires the power required by the power grid, the remaining capacity of each energy storage unit and the corresponding working status; Determine the unit, and determine the number of energy storage modules connected to the grid based on the power required by the grid and the working status of each energy storage unit; The control unit controls a corresponding number of energy storage modules to connect to the power grid according to the remaining capacity of each energy storage unit.

5. The distributed modular energy storage device according to claim 4, characterized in that: The determining unit comprises: A first determination subunit determines, according to the working state of each energy storage unit, a set remaining capacity range corresponding to its optimal working state; The second determination subunit determines the number of energy storage modules connected to the power grid according to the set remaining capacity range of each energy storage unit and the power required by the power grid.

6. The distributed modular energy storage device according to claim 4, characterized in that: The working state includes: a charging working state and a discharging working state.

7. The distributed modular energy storage device according to claim 5, characterized in that: The number of energy storage modules connected to the power grid is: the ratio of the power required by the power grid to the power of the energy storage modules when working in the optimal working state.

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