An electrochemical energy storage power station based on strong adaptability to the power grid

Abstract

The present invention relates to the field of electrochemical energy storage technology, and in particular to an electrochemical energy storage power station based on strong adaptability of a power grid, the power station comprising a battery energy storage system, which comprises a plurality of battery packs for storing and releasing electric energy and a frequency regulation unit for adjusting the charging and discharging power according to the frequency deviation of the power grid to achieve frequency regulation; a bidirectional converter for realizing bidirectional power conversion between the battery energy storage system and the power grid; a battery management unit for real-time detection of parameters such as voltage, current, and temperature of the battery energy storage system and determining the dynamic balance of battery charging and discharging; and a power prediction unit for determining whether the frequency regulation unit turns on a backup battery pack to adjust the frequency deviation of the power grid according to the change amplitude of the operating parameters of the power grid within a preset time; and an adjustment of the working process of the electrochemical energy storage power station according to the response time of the power grid dispatch and the energy efficiency of the electrochemical energy storage power station during operation.

Description

Technical Field

[0001] The present invention relates to the technical field of electrochemical energy storage, and in particular to an electrochemical energy storage power station based on strong adaptability of a power grid. Background Art

[0002] Energy storage technology adds a "storage" link to the "electricity production, transmission, distribution and consumption" of the power system, making the originally almost "rigid" system "flexible". Large-capacity battery energy storage has the characteristics of rapid absorption of energy and timely release, which can realize the time migration of energy and solve the problem of insufficient system power supply caused by the output volatility and uncertainty of new energy power generation. With technological breakthroughs in battery materials, manufacturing processes, system integration, operation and maintenance, the manufacturing and operation costs of energy storage have been greatly reduced, and the development potential of energy storage systems is huge, but the existing energy storage power stations have problems with high operating efficiency and low responsiveness to the power grid.

[0003] Chinese patent application publication number: CN116683500A discloses an active power dispatching method and system for an electrochemical energy storage power station, including the following steps: obtaining the current state of the electrochemical energy storage power station; collecting historical load data of the power system; collecting, sorting and forming power load-related data including weather, seasons, and holidays; combining historical load data and power load-related data to form a power load forecasting curve, and determining the active power output target of the electrochemical energy storage power station; optimizing and adjusting the active power output target; combining external environmental monitoring values ​​of temperature, humidity, and wind speed, first based on model prediction, then based on algorithm optimization, and finally outputting the active power dispatching instructions of the energy storage power station in the current dispatching cycle; adjusting the active power dispatching instructions of the energy storage power station in real time according to the real-time monitoring system for emergencies. The invention provides an active power dispatching method and system for an electrochemical energy storage power station, which can fully take into account various relevant factors, making the active power dispatching of the energy storage power station more reasonable.

[0004] It can be seen that the existing technology has the problem of inaccurate analysis of the operating parameters of the energy storage power station, which leads to low efficiency in adjusting the operating process of the energy storage power station and waste of resources. Summary of the invention

[0005] To this end, the present invention provides an electrochemical energy storage power station based on strong adaptability to the power grid, so as to overcome the problem in the prior art that the analysis of the operating parameters of the energy storage power station is not accurate enough, resulting in low efficiency in adjusting the operating process of the energy storage power station and causing waste of resources.

[0006] To achieve the above object, the present invention provides an electrochemical energy storage power station based on strong adaptability of the power grid, comprising:

[0007] A battery energy storage system, which includes a plurality of battery packs for storing and releasing electric energy and a frequency regulation unit for adjusting the charging and discharging power according to the frequency deviation of the power grid for frequency regulation;

[0008] A power conversion system connected to the battery energy storage system, comprising a bidirectional converter for performing bidirectional power conversion between the battery energy storage system and the power grid;

[0009] An energy management system connected to the power conversion system, comprising a battery management unit for real-time detection of parameters of each battery pack in the battery energy storage system and determination of a dynamic balance evaluation value of battery charging and discharging, and a power prediction unit for determining whether a frequency adjustment unit should start a backup battery pack to adjust a frequency deviation of a power grid according to a variation range of operating parameters of the power grid within a preset time;

[0010] An operation and maintenance management system, which is connected to the energy management system and is used to determine the adjustment amount of the preset dynamic balance evaluation value and the preset change range during the operation of the electrochemical energy storage power station according to the response time of the power grid dispatch and the energy efficiency of the electrochemical energy storage power station during operation;

[0011] The dynamic balance evaluation value is determined according to the parameters of each battery pack, the battery pack adopts a redundant design, and the frequency adjustment unit determines whether to start the backup battery pack according to the prediction result of the power prediction unit.

[0012] Furthermore, the frequency regulation unit determines to adjust the charging and discharging power according to the comparison result that the grid frequency deviation is greater than or equal to the preset frequency deviation, and the adjustment of the charging and discharging power includes increasing or decreasing the charging power, increasing or decreasing the discharging power, and switching between charging and discharging.

[0013] Furthermore, the grid frequency deviation is determined based on the difference between the ratio of the real-time operating parameter to the standard operating parameter and one, the preset frequency deviation is determined based on the historical average value of the grid frequency deviation, and the difference is taken as an absolute value.

[0014] Further, under the condition that the frequency adjustment unit determines to adjust the charging and discharging power, the battery management unit determines that the battery pack is qualified according to the comparison result that the dynamic balance evaluation value of the battery charging and discharging within the preset time is greater than or equal to the preset dynamic balance evaluation value, and the battery management unit determines that the battery pack is unqualified according to the comparison result that the dynamic balance evaluation value of the battery charging and discharging within the preset time is less than the preset dynamic balance evaluation value.

[0015] Furthermore, the dynamic balance evaluation value is determined according to the maximum parameter and the minimum parameter of each battery obtained by periodic measurement, and the preset dynamic balance evaluation value is determined according to the historical average value of the dynamic balance evaluation value of each battery group.

[0016] Furthermore, the power prediction unit determines that the frequency adjustment unit turns on the backup battery pack to adjust the grid frequency deviation based on a comparison result that the change range of the grid operation parameters within a preset time is greater than or equal to a preset change range.

[0017] Furthermore, the preset variation range is determined according to a historical average value of the variation range of the power grid operation parameter.

[0018] Furthermore, the operation and maintenance management system determines an adjustment amount for a preset dynamic balance evaluation value during the operation of the electrochemical energy storage power station based on a comparison result between a response time of the grid dispatch and a preset response time, and the operation and maintenance management system determines an adjustment amount for a preset change amplitude during the operation of the electrochemical energy storage power station based on a comparison result between the energy efficiency of the electrochemical energy storage power station during operation and a preset energy efficiency.

[0019] Furthermore, the response time of the grid dispatch is determined according to the time for the frequency regulation unit to regulate the grid frequency, the preset response time is determined according to the historical average value of the frequency regulation unit's grid regulation time with the same frequency deviation, the energy efficiency of the electrochemical energy storage power station during operation is determined according to the ratio of the output electric energy to the input electric energy, and the preset energy efficiency is determined according to the historical average value of the energy efficiency of the electrochemical energy storage power station.

[0020] Furthermore, the adjustment amount of the preset dynamic balance evaluation value is negatively correlated with the response time of the power grid dispatch, and the adjustment amount of the preset change range is negatively correlated with the energy efficiency of the electrochemical energy storage power station during operation.

[0021] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention determines the adjustment of charging and discharging power according to the comparison result of the grid frequency deviation and the preset frequency deviation. If the grid frequency deviation is greater than or equal to the preset frequency deviation, it means that the actual operating energy of the grid is higher than the standard operating energy. At this time, it is necessary to adjust the battery energy storage system to the charging mode to absorb excess energy. If the grid frequency deviation is less than the preset frequency deviation, it means that the actual operating energy of the grid is lower than the standard operating energy. At this time, it is necessary to adjust the battery energy storage system to the discharging mode to release energy to ensure the normal operation of the grid. The above method improves the accuracy of the analysis of the operating parameters of the electrochemical energy storage power station and thus improves the strong adaptability of the electrochemical energy storage power station.

[0022] Furthermore, the present invention calculates a dynamic balance evaluation value of the battery pack based on the maximum and minimum parameters of each battery obtained through periodic measurement. If the dynamic balance evaluation value is greater than or equal to a preset dynamic balance evaluation value, it indicates that there are unqualified batteries in the battery pack, and the battery pack needs to be adjusted. If the dynamic balance evaluation value is less than the preset dynamic balance evaluation value, it indicates that there are no unqualified batteries in the battery pack, and the cause of the deviation frequency of the power grid is further analyzed. The above method improves the accuracy of the analysis of the operating parameters of the energy storage power station and thus improves the efficiency of adjusting the operating process of the energy storage power station to reduce resource waste.

[0023] Furthermore, the present invention determines whether the frequency regulation unit turns on the backup battery pack to adjust the grid frequency deviation according to the change amplitude of the grid operation parameters within a preset time. If the change amplitude is greater than or equal to the preset change amplitude, it means that the power demand of the grid will change greatly due to external reasons. At this time, the grid needs to dispatch the power in the battery energy storage system. The frequency regulation unit turns on the backup battery pack to quickly respond to grid dispatch. The above method improves the accuracy of the grid operation parameter analysis and thus improves the response time to grid dispatch, thereby improving the adaptability of the electrochemical energy storage power station.

[0024] Furthermore, the present invention determines the adjustment of the preset dynamic balance evaluation value during the operation of the electrochemical energy storage power station according to the comparison result between the response time of the battery energy storage system during the operation of the electrochemical energy storage power station and the preset response time. If the response time is greater than or equal to the preset response time, it means that the battery energy storage system has a long response time to the grid dispatch due to the unqualified battery pack. At this time, it is necessary to adjust the judgment parameter for judging whether the battery pack is qualified. If the response time is less than the preset response time, it is necessary to analyze the energy efficiency of the electrochemical energy storage power station to determine the amount of resource waste during the operation of the electrochemical energy storage power station. If the energy efficiency is greater than or equal to the preset energy efficiency, it means that the energy loss during the operation of the electrochemical energy storage power station is small. If the energy efficiency is less than the preset energy efficiency, it means that the battery energy storage system cannot timely retain the required energy due to the huge reduction in the power required by the grid during the operation of the electrochemical energy storage power station, resulting in a large amount of energy loss during the grid adjustment. At this time, it is necessary to adjust the judgment parameter of whether the frequency adjustment unit turns on the backup battery pack to adjust the grid frequency deviation. The above method improves the accuracy of the analysis of the operation process of the electrochemical energy storage power station and thus improves the resource utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of an electrochemical energy storage power station based on strong adaptability to the power grid according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of an electrochemical energy storage power station energy management system based on strong grid adaptability according to an embodiment of the present invention;

[0027] Figure 3 This is a flowchart of a process for determining whether a battery pack is qualified based on an electrochemical energy storage power station with strong grid adaptability according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0030] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0031] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] See also Figure 1-Figure 3 As shown, Figure 1 This is a schematic diagram of the structure of an electrochemical energy storage power station based on strong adaptability to the power grid according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of an electrochemical energy storage power station energy management system based on strong grid adaptability according to an embodiment of the present invention; Figure 3 This is a flowchart of a process for determining whether a battery pack is qualified based on an electrochemical energy storage power station with strong grid adaptability according to an embodiment of the present invention.

[0033] The electrochemical energy storage power station of the embodiment of the present invention is based on strong adaptability of the power grid, including:

[0034] A battery energy storage system, which includes a plurality of battery packs for storing and releasing electric energy and a frequency regulation unit for adjusting the charging and discharging power according to the frequency deviation of the power grid to achieve frequency regulation;

[0035] a power conversion system connected to the electrothermal energy storage system, comprising a bidirectional converter for realizing bidirectional power conversion between the battery energy storage system and the power grid;

[0036] An energy management system connected to the power conversion system, comprising a battery management unit for real-time detection of parameters of each battery pack in the battery energy storage system and determination of a dynamic balance of battery charge and discharge, and a power prediction unit for determining whether a frequency adjustment unit should activate a backup battery pack to adjust a frequency deviation of a power grid according to a variation of operating parameters of the power grid within a preset time;

[0037] An operation and maintenance management system, which is connected to the energy management system and is used to determine the adjustment amount of the preset dynamic balance evaluation value and the preset change range during the operation of the electrochemical energy storage power station according to the response time of the power grid dispatch and the energy efficiency of the electrochemical energy storage power station during operation;

[0038] The battery pack adopts a redundant design, and the frequency adjustment unit determines whether to start the backup battery pack according to the prediction result of the power prediction unit.

[0039] The operating parameters of the power grid in the embodiment of the present invention include but are not limited to "voltage, current and power", and the preset time is set to 500 milliseconds.

[0040] Specifically, the frequency adjustment unit determines to adjust the charging and discharging power, including determining to adjust the charging and discharging power according to a comparison result of the grid frequency deviation D and the preset frequency deviation D0;

[0041] If D≥D0, the frequency adjustment unit determines that the charging and discharging power needs to be adjusted;

[0042] If D<D0, the frequency adjustment unit determines that there is no need to adjust the charging and discharging power;

[0043] The value of the preset frequency deviation D0 is the historical average value of the grid frequency deviation, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0044] In the embodiment of the present invention, the grid frequency deviation is based on the absolute value of the difference between the ratio of the real-time operating parameter and the standard operating parameter and one. The adjustment of the charging and discharging power includes increasing or decreasing the charging power, increasing or decreasing the discharging power, and switching between charging and discharging. The value range of the preset frequency deviation is set to 0 Hz to 0.2 Hz, and the value of the preset frequency deviation is preferably 0.18 Hz, but the above value is not limited to this. Those skilled in the art can also adjust the value according to actual needs.

[0045] The present invention determines the adjustment of charging and discharging power according to the comparison result of the grid frequency deviation and the preset frequency deviation. If the grid frequency deviation is greater than or equal to the preset frequency deviation, it means that the actual operating energy of the grid is higher than the standard operating energy. At this time, it is necessary to adjust the battery energy storage system to the charging mode to absorb excess energy. If the grid frequency deviation is less than the preset frequency deviation, it means that the actual operating energy of the grid is lower than the standard operating energy. At this time, it is necessary to adjust the battery energy storage system to the discharging mode to release energy to ensure the normal operation of the grid. The above method improves the accuracy of the analysis of the operating parameters of the electrochemical energy storage power station and thus improves the strong adaptability of the electrochemical energy storage power station.

[0046] Specifically, the frequency adjustment unit determines whether the battery pack is qualified according to the comparison result between the dynamic balance evaluation value P of the battery charge and discharge within a preset time and the preset dynamic balance evaluation value P0 under the condition that the charge and discharge power is adjusted;

[0047] If P≥P0, the battery management unit determines that the battery pack is unqualified;

[0048] If P<P0, the battery management unit determines that the battery pack is qualified;

[0049] Among them, the value of the preset dynamic balance evaluation value P0 is the historical average value of the dynamic balance evaluation value of the battery pack. The value range of the preset dynamic balance evaluation value is set to 0 to 0.4, and the value of the preset dynamic balance evaluation value is preferably 0.3, but the above value is not limited to this. Those skilled in the art can also adjust the value according to actual needs.

[0050] Specifically, the dynamic balance evaluation value P is calculated by the following formula:

[0051]

[0052] Wherein, N represents the number of each battery parameter measured periodically during the operation of the battery pack, Mmaxi represents the parameter of the i-th battery among the five maximum battery parameters, and Mminj represents the parameter of the j-th battery among the five minimum battery parameters.

[0053] The parameters of the battery described in the embodiment of the present invention include but are not limited to "input voltage, input current, output voltage and output current". The dynamic balance evaluation values ​​are calculated using the above parameters respectively, and then the average value of the dynamic balance evaluation values ​​of the above parameters is used as the parameter for judging whether the battery is qualified. For example, the dynamic balance evaluation value calculated using the input voltage parameter is 0.31, the dynamic balance evaluation value calculated using the input current parameter is 0.42, the dynamic balance evaluation value calculated using the output voltage parameter is 0.35, and the dynamic balance evaluation value calculated using the output current parameter is 0.25. The average value of the above dynamic balance evaluation values, 0.3325, is used as the judgment parameter for judging whether the battery pack is qualified.

[0054] Specifically, under the condition that the battery management unit determines that the battery pack is unqualified, the battery management unit determines to repair or replace the battery pack.

[0055] The present invention calculates the dynamic balance evaluation value of the battery pack according to the maximum and minimum parameters of each battery obtained by periodic measurement. If the dynamic balance evaluation value is greater than or equal to the preset dynamic balance evaluation value, it means that there are unqualified batteries in the battery pack, and the battery pack needs to be adjusted. If the dynamic balance evaluation value is less than the preset dynamic balance evaluation value, it means that there are no unqualified batteries in the battery pack. At this time, the further analysis of the cause of the deviation frequency of the power grid is carried out. The above method improves the accuracy of the analysis of the operating parameters of the energy storage power station and thus improves the efficiency of adjusting the operating process of the energy storage power station to reduce resource waste.

[0056] Specifically, under the condition that the battery management unit determines that the battery group is qualified, the power prediction unit determines whether the frequency adjustment unit turns on the backup battery group to adjust the grid frequency deviation according to the comparison result of the change amplitude B of the operating parameters of the grid within the preset time and the preset change amplitude B0;

[0057] If B≥B0, the power prediction unit determines that the frequency adjustment unit turns on the backup battery pack to adjust the grid frequency deviation;

[0058] If B<B0, the power prediction unit determines that the frequency adjustment unit does not start the backup battery group to adjust the grid frequency deviation;

[0059] Among them, the preset change amplitude B0 is 5% of the nominal voltage. For example, the nominal voltage of the power grid is 220 kV, and the preset change amplitude is 11 kV. However, the above value is not limited to this. Technical personnel in this field can also adjust the value according to actual needs.

[0060] In the embodiment of the present invention, the variation range of the operating voltage of the power grid within the preset time is the variation amount of the operating voltage within the preset time.

[0061] The present invention determines whether the frequency regulation unit turns on the backup battery pack to adjust the grid frequency deviation according to the change amplitude of the grid operation parameters within a preset time. If the change amplitude is greater than or equal to the preset change amplitude, it means that the power demand of the grid will change greatly due to external reasons. At this time, the grid needs to dispatch the power in the battery energy storage system. The frequency regulation unit turns on the backup battery pack to quickly respond to the grid dispatch. The above method improves the accuracy of the grid operation parameter analysis and thus improves the response time to the grid dispatch and thus improves the strong adaptability of the electrochemical energy storage power station.

[0062] Specifically, the operation and maintenance management system determines that the operation process adjustment of the electrochemical energy storage power station includes:

[0063] The operation and maintenance management system determines an adjustment amount of a preset dynamic balance evaluation value during the operation of the electrochemical energy storage power station according to a first comparison result of a response time S of the grid dispatch and a preset response time S0;

[0064] The operation and maintenance management system determines an adjustment amount for a preset change range during the operation of the electrochemical energy storage power station based on a second comparison result of a response time S of a power grid dispatch and a preset response time S0 and a first comparison result of an energy efficiency H of an electrochemical energy storage power station during operation and a preset energy efficiency H0.

[0065] In a specific embodiment, it is set that:

[0066] S≥S0 is the first comparison result between the response time of the power grid dispatch and the preset response time;

[0067] S<S0 is a second comparison result between the response time of the power grid dispatch and the preset response time;

[0068] H<H0 is the first comparison result between the energy efficiency of the electrochemical energy storage power station during operation and the preset energy efficiency;

[0069] H≥H0 is a second comparison result between the energy efficiency of the electrochemical energy storage power station during operation and the preset energy efficiency.

[0070] The response time of the grid dispatch in the embodiment of the present invention is determined according to the time for the frequency regulation unit to regulate the grid frequency, the preset response time is determined according to the historical average value of the frequency regulation unit's grid regulation time with the same frequency deviation, the energy efficiency of the electrochemical energy storage power station during operation is determined according to the ratio of the output electric energy to the input electric energy, the preset energy efficiency is determined according to the historical average value of the energy efficiency of the electrochemical energy storage power station, the value range of the preset energy efficiency is set to 70% to 90%, and the value of the preset energy efficiency is preferably 80%, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0071] In a specific embodiment, it is set that: if S≥S0, the operation and maintenance management system determines to adjust the preset dynamic balance evaluation value during the operation of the electrochemical energy storage power station;

[0072] If S<S0, the operation and maintenance management system determines to make a secondary determination on the adjustment of the operation process of the electrochemical energy storage power station.

[0073] Specifically, under the condition that the operation and maintenance management system determines to make a secondary judgment on the adjustment of the operation process of the electrochemical energy storage power station, the operation and maintenance management system determines to adjust the operation process of the electrochemical energy storage power station according to the comparison result of the energy efficiency H of the electrochemical energy storage power station and the preset energy efficiency H0;

[0074] If H<H0, the operation and maintenance management system determines to adjust the preset change range during the operation of the electrochemical energy storage power station;

[0075] If H≥H0, the operation and maintenance management system determines not to adjust the operation process of the electrochemical energy storage power station.

[0076] Specifically, the operation and maintenance management system determines to adjust the preset dynamic balance evaluation value during the operation of the electrochemical energy storage power station by a first adjustment coefficient K1;

[0077] Under the condition that the preset change range is adjusted during the operation of the electrochemical energy storage power station, the operation and maintenance management system determines to adjust the preset change range with a second adjustment coefficient K2.

[0078] Specifically, the first adjustment coefficient K1 is calculated and set by the following formula:

[0079]

[0080] The second adjustment coefficient K2 is calculated and set by the following formula:

[0081] K2 = log2(H0-H+1.75);

[0082] The adjusted preset dynamic balance evaluation value P0' is set to P0'=K1×P0;

[0083] The adjusted preset variation range B0' is set to B0'=K2×B0.

[0084] The present invention determines the adjustment of the preset dynamic balance evaluation value during the operation of the electrochemical energy storage power station according to the comparison result between the response time of the battery energy storage system and the preset response time during the operation of the electrochemical energy storage power station. If the response time is greater than or equal to the preset response time, it means that the battery energy storage system has a long response time to the grid dispatch due to an unqualified battery pack. At this time, it is necessary to adjust the judgment parameter for judging whether the battery pack is qualified. If the response time is less than the preset response time, it is necessary to analyze the energy efficiency of the electrochemical energy storage power station to determine the amount of resource waste during the operation of the electrochemical energy storage power station. If the energy efficiency is greater than or equal to the preset energy efficiency, it means that the energy loss during the operation of the electrochemical energy storage power station is small. If the energy efficiency is less than the preset energy efficiency, it means that the battery energy storage system cannot timely retain the required energy due to the huge reduction in the power required by the grid during the operation of the electrochemical energy storage power station, resulting in a large amount of energy loss during the grid adjustment. At this time, it is necessary to adjust the judgment parameter of whether the frequency adjustment unit turns on the backup battery pack to adjust the grid frequency deviation. The above method improves the accuracy of the analysis of the operation process of the electrochemical energy storage power station and thus improves the resource utilization rate.

[0085] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0086] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An electrochemical energy storage power station based on strong adaptability to the power grid, characterized in that: include: A battery energy storage system, which includes a plurality of battery packs for storing and releasing electric energy and a frequency regulation unit for adjusting the charging and discharging power according to the frequency deviation of the power grid for frequency regulation; A power conversion system connected to the battery energy storage system, comprising a bidirectional converter for performing bidirectional power conversion between the battery energy storage system and the power grid; An energy management system connected to the power conversion system, comprising a battery management unit for real-time detection of parameters of each battery pack in the battery energy storage system and determination of a dynamic balance evaluation value of battery charging and discharging, and a power prediction unit for determining whether a frequency adjustment unit should start a backup battery pack to adjust a frequency deviation of a power grid according to a variation range of operating parameters of the power grid within a preset time; An operation and maintenance management system, which is connected to the energy management system and is used to determine the adjustment amount of the preset dynamic balance evaluation value and the preset change range during the operation of the electrochemical energy storage power station according to the response time of the power grid dispatch and the energy efficiency of the electrochemical energy storage power station during operation; If the response time of the grid dispatch is greater than or equal to the preset response time, the operation and maintenance management system determines to adjust the preset dynamic balance evaluation value during the operation of the electrochemical energy storage power station with a first adjustment coefficient; If the response time of the grid dispatch is less than the preset response time and the energy efficiency of the electrochemical energy storage power station is less than the preset energy efficiency, the operation and maintenance management system determines to adjust the preset change amplitude during the operation of the electrochemical energy storage power station with a second adjustment coefficient; The variation range of the operating parameters of the power grid within the preset time is the variation of the operating voltage within the preset time; the dynamic balance evaluation value is determined according to the parameters of each battery pack, the battery pack adopts a redundant design, and the frequency adjustment unit determines whether to start the backup battery pack according to the prediction result of the power prediction unit; The dynamic balance evaluation value is calculated by the following formula and is set: ； Wherein, P represents the dynamic balance evaluation value, N represents the number of each battery parameter measured periodically during the operation of the battery pack, Mmaxi represents the parameter of the i-th battery among the five maximum battery parameters, and Mminj represents the parameter of the j-th battery among the five minimum battery parameters.

2. The electrochemical energy storage power station based on strong grid adaptability according to claim 1 is characterized in that: The frequency adjustment unit determines to adjust the charging and discharging power according to the comparison result that the grid frequency deviation is greater than or equal to the preset frequency deviation, and the adjustment of the charging and discharging power includes increasing or decreasing the charging power, increasing or decreasing the discharging power, and switching between charging and discharging.

3. The electrochemical energy storage power station based on strong grid adaptability according to claim 2 is characterized in that: The grid frequency deviation is determined based on the difference between the ratio of the real-time operating parameter to the standard operating parameter and one, and the preset frequency deviation is determined based on the historical average value of the grid frequency deviation, and the difference is taken as an absolute value.

4. The electrochemical energy storage power station based on strong grid adaptability according to claim 3 is characterized in that: The frequency adjustment unit determines under the condition of adjusting the charging and discharging power that the battery management unit determines that the battery pack is qualified according to the comparison result that the dynamic balance evaluation value of the battery charging and discharging within the preset time is greater than or equal to the preset dynamic balance evaluation value, and the battery management unit determines that the battery pack is unqualified according to the comparison result that the dynamic balance evaluation value of the battery charging and discharging within the preset time is less than the preset dynamic balance evaluation value.

5. The electrochemical energy storage power station based on strong grid adaptability according to claim 4 is characterized in that: The dynamic balance evaluation value is determined according to the maximum parameter and the minimum parameter of each battery obtained by periodic measurement, and the preset dynamic balance evaluation value is determined according to the historical average value of the dynamic balance evaluation value of each battery group.

6. The electrochemical energy storage power station based on strong grid adaptability according to claim 5 is characterized in that: The power prediction unit determines that the frequency adjustment unit turns on the backup battery pack to adjust the grid frequency deviation based on the comparison result that the change range of the grid operation parameter within the preset time is greater than or equal to the preset change range.

7. The electrochemical energy storage power station based on strong grid adaptability according to claim 6 is characterized in that: The preset variation range is determined according to the historical average value of the variation range of the power grid operation parameter.

8. The electrochemical energy storage power station based on strong grid adaptability according to claim 7 is characterized in that: The operation and maintenance management system determines the adjustment amount of the preset dynamic balance evaluation value during the operation of the electrochemical energy storage power station based on the comparison result of the response time of the power grid dispatch and the preset response time. The operation and maintenance management system determines the adjustment amount of the preset change amplitude during the operation of the electrochemical energy storage power station based on the comparison result of the energy efficiency of the electrochemical energy storage power station during operation and the preset energy efficiency.

9. The electrochemical energy storage power station based on strong grid adaptability according to claim 8 is characterized in that: The response time of the grid dispatch is determined according to the time for the frequency regulation unit to regulate the grid frequency, the preset response time is determined according to the historical average value of the frequency regulation unit's grid regulation time with the same frequency deviation, the energy efficiency of the electrochemical energy storage power station during operation is determined according to the ratio of the output electric energy to the input electric energy, and the preset energy efficiency is determined according to the historical average value of the energy efficiency of the electrochemical energy storage power station.

10. The electrochemical energy storage power station based on strong grid adaptability according to claim 9, characterized in that: The adjustment amount of the preset dynamic balance evaluation value is negatively correlated with the response time of the power grid dispatch, and the adjustment amount of the preset change amplitude is negatively correlated with the energy efficiency of the electrochemical energy storage power station during operation.

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