Parallel operation method supporting hot plug and energy storage system

Abstract

The invention provides a hot plug supporting parallel operation method and an energy storage system.The method comprises the steps that if system current is detected, the current type of the system current is confirmed, and a first preset set is controlled to be charged or a second preset set is controlled to be discharged according to the current type of the system current, the first preset set comprises a charging set and a charging waiting set, the second preset set comprises a discharging set and a discharging waiting set, the battery packs in the charging set and the charging waiting set are used for charging, and the battery packs in the discharging set and the discharging waiting set are used for discharging; and if a new battery pack is detected, re-dividing the sets to obtain a new first preset set and a new second preset set. According to the invention, hot plug parallel operation charging and discharging can be supported.

Description

Technical Field

[0001] The present invention relates to the field of charge and discharge technology, and in particular to a hot-swap paralleling method and an energy storage system. Background Art

[0002] At present, when the energy storage system is parallel-connected for capacity expansion, it is necessary to shut down the equipment first, then connect the added battery pack to the energy storage system, restart the energy storage system after the connection is completed, and power the equipment. If the energy storage system is parallel-connected for capacity expansion, it is easy to generate huge circulating currents due to the large voltage difference between different battery packs, causing damage to the battery packs and posing safety hazards. In other words, the current energy storage system does not support hot-swappable parallel connection. Summary of the invention

[0003] The present invention provides a method and an energy storage system supporting hot-swap parallel operation, aiming to solve the problem that the current energy storage system does not support hot-swap parallel operation.

[0004] In a first aspect, the present invention provides a method for supporting hot-swap parallel operation, the method comprising:

[0005] If the system current is detected, confirm the current type of the system current, and control the first preset set to charge or control the second preset set to discharge according to the current type of the system current, wherein the first preset set includes a charging set and a charging waiting set, and the second preset set includes a discharging set and a discharging waiting set, the battery packs in the charging set and the charging waiting set are used for charging, and the battery packs in the discharging set and the discharging waiting set are used for discharging;

[0006] If a new battery pack is detected, the set is re-divided to obtain a new first preset set and a new second preset set.

[0007] In a second aspect, the present invention provides an energy storage system, the energy storage system comprising any one of the hot-swap and parallel support methods described above.

[0008] The present invention discloses a method and energy storage system supporting hot-swap parallel operation, the method comprising: if a system current is detected, confirming the current type of the system current, and controlling the first preset set to charge or the second preset set to discharge according to the current type of the system current, wherein the first preset set includes a charging set and a charging waiting set, and the second preset set includes a discharging set and a discharging waiting set, the battery packs in the charging set and the charging waiting set are used for charging, and the battery packs in the discharging set and the discharging waiting set are used for discharging; if a new battery pack is detected, the set is re-divided to obtain a new first preset set and a new second preset set. In the embodiment of the present invention, when the system current is detected, the first preset set can be controlled to charge or the second preset set can be controlled to discharge according to the current type of the system current, and when a new battery pack is detected, the set is re-divided to obtain a new first preset set and a new second preset set, so that the new battery pack can be connected in parallel while continuing to charge or discharge, thereby supporting hot-swap parallel operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0010] Figure 1 is a flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0011] Figure 2 This is a first sub-flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0012] Figure 3 is a second sub-flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0013] Figure 4 is a third sub-flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0014] Figure 5 is a fourth sub-flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0015] Figure 6 is a fifth sub-flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0016] Figure 7 is a sixth sub-flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0017] Figure 8 is a seventh sub-flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0018] Fig. 9 is an eighth sub-flow chart of a method for supporting hot-swap parallel operation provided by an embodiment of the present invention;

[0019] Fig.10 It is a schematic diagram of charging and discharging of an energy storage system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, operations, elements, components and / or groups thereof.

[0022] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, the singular forms of "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should also be further understood that the term "and / or" used in the specification of the present invention and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0023] In addition, the directional terms mentioned in the present invention, such as "upper", "lower", "front", "back", "left", "right", "inner", "outer", "side", etc., are only for reference to the directions of the attached drawings and the use status of the product. Therefore, the directional terms used are used to illustrate and understand the present invention, but not to limit the present invention. In addition, in the drawings, structures with similar or identical structures are represented by the same reference numerals.

[0024] See also Figure 1 The present invention provides a method for supporting hot-swap parallel operation, which can be applied to an energy storage system and can support hot-swap parallel operation charging and discharging. The method for supporting hot-swap parallel operation includes S110-S120.

[0025] S110, if the system current is detected, confirm the current type of the system current, and control the charging of the first preset set or the discharging of the second preset set according to the current type of the system current, wherein the first preset set includes a charging set and a charging waiting set, and the second preset set includes a discharging set and a discharging waiting set, the battery packs in the charging set and the charging waiting set are used for charging, and the battery packs in the discharging set and the discharging waiting set are used for discharging.

[0026] In an embodiment of the present invention, the energy storage system may include multiple battery packs, a battery management system, and a switch unit. The battery pack is used to store energy and output energy. The battery pack can be charged to store energy and discharged to output energy. The battery management system is used to monitor external parameters, including but not limited to voltage, current, temperature and other parameters, so that the battery pack status can be detected in real time, providing data support for the use and maintenance of the battery pack.

[0027] When the system current is detected, that is, the energy storage system starts to operate, the type of the system current can be confirmed, and the first preset set can be controlled to charge or the second preset set can be controlled to discharge according to the current type. The current type of the system current can include charging current and discharging current. The charging current indicates that the system is in a charging state, and the discharging current indicates that the system is in a discharging state.

[0028] All battery packs in the system can be divided into sets, that is, two sets can be preset, the two sets are a first preset set and a second preset set, the first preset set includes a charging set and a charging waiting set, the second preset set includes a discharging set and a discharging waiting set, the charging set means that when the system current is a charging current, the battery packs in the charging set can be charged, the charging waiting set refers to the set of battery packs that need to be charged but do not meet the charging conditions, similarly, the discharging set means that when the system current is a discharging current, the battery packs in the discharging set can be discharged, and the discharging waiting set refers to the set of battery packs that can be discharged but do not meet the discharging conditions.

[0029] By presetting the above four sets, the battery packs are classified into corresponding sets. When the energy storage system is running, the battery packs in different sets can be controlled to work according to the operation mode. The operation mode may include a charging mode and a discharging mode. The charging mode corresponds to the charging current, and the discharging mode corresponds to the discharging current. When the system is running in the charging mode, the battery packs in the charging set start to charge, and when the battery packs in the charging waiting set meet the charging conditions, they are incorporated into the charging set. When the system is running in the discharging mode, the battery packs in the discharging set start to discharge, and when the battery packs in the discharging waiting set meet the discharging conditions, they are incorporated into the discharging set. In addition, it should be noted that for a battery pack, it can belong to both the first preset set and the second preset set, and its specific affiliation is determined by the operation mode of the system. For example, for a battery pack, it can belong to the charging set in the charging mode, and it can belong to the discharging waiting set in the discharging mode.

[0030] like Fig.10 As shown, Fig.10 The system includes two groups of battery modules, namely a first battery module and a second battery module. The battery packs in the first battery module are in a charging mode, and the battery packs in the second battery module are in a discharging mode. That is, when the system is in the charging mode, the system charges the battery packs in the first battery module through the charger, and when the system is in the discharging mode, the system supplies power to the load through the battery packs in the second battery module.

[0031] S120: If a new battery pack is detected, re-dividing the set to obtain a new first preset set and a new second preset set.

[0032] In the embodiment of the present invention, it can be known from the above content that the first preset set includes a charging set and a charging waiting set, and the second preset set includes a discharging set and a discharging waiting set. Battery packs that do not meet the charging conditions will be placed in the charging waiting set to avoid affecting the battery packs in the charging set, and battery packs that do not meet the discharging conditions will be placed in the discharging waiting set to avoid affecting the battery packs in the discharging set. When the system is running in any mode, if a new battery pack is added, that is, parallel connection is required, the system can re-traverse all battery packs, and then re-divide the sets according to the voltage of each battery pack to avoid the newly added battery pack from affecting other battery packs.

[0033] For example, after the system re-traverses all battery packs, it confirms the voltage of the new battery pack and the current operating mode of the system. If the current operating mode of the system is charging mode, and the voltage of the new battery pack does not meet the charging conditions, the new battery pack can be placed in the charging waiting set. If the voltage of the new battery pack meets the charging conditions, the new battery pack can be placed in the charging set and charged together with the battery pack being charged. If the voltage of the new battery pack is low and much lower than the voltage of other battery packs, the new battery pack can be charged first. At this time, the system needs to exit the parallel mode and charge the new battery pack first. In the discharge mode, if there is a new battery pack that needs to be paralleled, the parallel process can refer to the parallel process in the charging mode. For example, if the new battery pack does not meet the discharge conditions, it is added to the discharge waiting set. If the new battery pack meets the discharge conditions, it is added to the discharge set. If the voltage of the new battery pack is much higher than that of other battery packs, the system exits the parallel mode and discharges the new battery pack first.

[0034] See also Figure 2 In some embodiments, such as in the present embodiment, the method for supporting hot-swap parallel operation may include steps S130-S140.

[0035] S130, calculating the voltages of all battery packs to obtain a first target voltage and a second target voltage, wherein the first target voltage is a minimum voltage value among all the battery packs, and the second target voltage is a maximum voltage value among all the battery packs;

[0036] S140: Divide all the battery packs into groups according to the first target voltage and the second target voltage.

[0037] In the embodiment of the present invention, the first target voltage is the minimum voltage of all battery packs, and the second target voltage is the maximum voltage of all battery packs. For example, there are four battery packs A, B, C, and D, and the voltages of the four battery packs A, B, C, and D decrease in sequence, then the first target voltage is the voltage corresponding to the D battery pack, and the second target voltage is the voltage corresponding to the A battery pack. After determining the first target voltage and the second target voltage, each battery pack can be divided into sets according to the relationship between the voltage of each battery pack and the first target voltage and the second target voltage.

[0038] See also Figure 3 In some embodiments, such as in the present embodiment, the step S140 may include steps S141-S144.

[0039] S141, obtaining one of the battery packs from all the battery packs and setting it as a battery pack to be classified, and confirming the voltage of the battery pack to be classified;

[0040] S142, calculating the difference between the voltage of the battery pack to be classified and the first target voltage to obtain a first difference;

[0041] S143: If the first difference is less than a preset parallel threshold, the battery pack to be classified is merged into the charging set.

[0042] S144: If the first difference is greater than or equal to the preset parallel threshold, the battery pack to be classified is merged into the charging waiting set.

[0043] In the embodiment of the present invention, when dividing the set, the voltage of each battery pack is calculated in turn, and the relationship between the voltage of each battery pack and the first target voltage and the second target voltage is confirmed. For example, any battery pack can be selected from all battery packs to obtain a battery pack to be classified, and then the voltage of the battery pack to be classified is calculated.

[0044] After obtaining the voltage of the battery pack to be classified, the difference between the voltage of the battery pack to be classified and the first target voltage is calculated to obtain the first difference. When the first difference is less than the preset parallel threshold, the battery pack to be classified is incorporated into the charging set. When the first difference is greater than or equal to the preset parallel threshold, the battery pack to be classified is incorporated into the charging waiting set. For example, there are four battery packs A, B, C and D, and the voltages of the four battery packs A, B, C and D decrease in sequence. The first target voltage is the voltage corresponding to the D battery pack. If the difference between the voltage of the C battery pack and the voltage of the D battery pack is less than the preset parallel threshold, the C battery pack is placed in the charging set. If the difference between the voltage of the C battery pack and the voltage of the D battery pack is greater than or equal to the preset parallel threshold, the C battery pack is placed in the charging waiting set.

[0045] See also Figure 4 In some embodiments, such as in the present embodiment, the step S140 may include steps S145-S147.

[0046] S145, calculating the difference between the second target voltage and the voltage of the battery pack to be classified to obtain a second difference;

[0047] S146: If the second difference is less than the preset parallel threshold, the battery pack to be classified is incorporated into the discharge set.

[0048] S147: If the second difference is greater than or equal to the preset parallel threshold, the battery pack to be classified is incorporated into the discharge waiting set.

[0049] In an embodiment of the present invention, after obtaining the voltage of the battery pack to be classified, the difference between the second target voltage and the voltage of the battery pack to be classified is calculated to obtain the second difference. When the second difference is less than the preset parallel threshold, the battery pack to be classified is incorporated into the discharge set. When the second difference is greater than or equal to the preset parallel threshold, the battery pack to be classified is incorporated into the discharge waiting set. For example, there are four battery packs A, B, C and D, and the voltages of the four battery packs A, B, C and D decrease in sequence. The second target voltage is the voltage corresponding to the A battery pack. If the difference between the voltage of the A battery pack and the voltage of the C battery pack is less than the preset parallel threshold, the C battery pack is placed in the discharge set. If the difference between the voltage of the A battery pack and the voltage of the C battery pack is greater than or equal to the preset parallel threshold, the C battery pack is placed in the discharge waiting set.

[0050] See also Figure 5 In some embodiments, such as in this embodiment, the step S110 may include steps S111-S112.

[0051] S111, if the current type is a charging current, controlling the charging set to charge, and confirming whether there is a battery pack in the charging waiting set whose voltage satisfies a first preset condition;

[0052] S112: If there is a battery pack in the charging waiting set whose voltage satisfies the first preset condition, the battery pack that satisfies the first preset condition is incorporated into the charging set.

[0053] In an embodiment of the present invention, the operation mode of the system may include a charging mode and a discharging mode. The charging mode corresponds to the charging current. When the system operates in the charging mode, the charging circuit of the charging set is turned on. While charging the battery packs in the charging set, the system will also confirm in real time whether there is a battery pack in the charging waiting set whose voltage meets the first preset condition. When there is a battery pack in the charging waiting set whose voltage meets the first preset condition, the battery pack that meets the first preset condition is placed in the charging set. The first preset condition may be a condition when dividing the set, that is, the voltage of the battery pack in the charging waiting set is calculated. When the difference between the voltage of the battery pack in the charging waiting set and the first target voltage is less than the preset parallel threshold, the battery pack in the charging waiting set is merged into the charging set.

[0054] See also Figure 6 In some embodiments, such as in the present embodiment, the step S110 may include steps S113-S114.

[0055] S113, if the current type is a discharge current, controlling the discharge set to discharge, and confirming whether there is a battery pack in the discharge waiting set whose voltage satisfies a second preset condition;

[0056] S114: If there is a battery pack in the discharge waiting set whose voltage satisfies the second preset condition, the battery pack that satisfies the second preset condition is incorporated into the discharge set.

[0057] In the embodiment of the present invention, the operation mode of the system may include a charging mode and a discharging mode. The discharging mode corresponds to the discharging current. When the system operates in the discharging mode, the discharging circuit of the discharging set is turned on. While discharging the battery packs in the discharging set, the system will also confirm in real time whether there is a battery pack in the discharging waiting set whose voltage meets the second preset condition. When there is a battery pack in the discharging waiting set whose voltage meets the second preset condition, the battery pack meeting the second preset condition is placed in the discharging set. The second preset condition may be a condition when dividing the set, that is, the voltage of the battery pack in the discharging waiting set is calculated. When the difference between the second target voltage and the voltage of the battery pack in the discharging waiting set is less than the preset parallel threshold, the battery pack in the discharging waiting set is merged into the discharging set.

[0058] See also Figure 7 In some embodiments, such as in the present embodiment, the method for supporting hot-swap parallel operation may include steps S150-S170.

[0059] S150, acquiring a set of battery packs connected in parallel last time to obtain a first set, and calculating an intersection of the first set and the discharge set or the charge set to obtain a second set;

[0060] S160, calculating a difference between the first set and the discharging set or the charging set to obtain a third set;

[0061] S170: Calculate a difference between the discharge set or the charge set and the first set to obtain a fourth set.

[0062] In an embodiment of the present invention, the first set is the set of battery packs at the time of the last parallel connection, and the second set is the intersection of the first set and the discharge set or the charge set, that is, the second set can be the intersection of the first set and the discharge set, or the intersection of the first set and the charge set, depending on whether the system operates in the discharge mode or the charge mode.

[0063] The third set is the difference between the first set and the discharge set or the charge set, that is, the third set can be the difference between the first set and the discharge set, or the difference between the first set and the charge set, depending on whether the system operates in the discharge mode or the charge mode.

[0064] The fourth set is a difference set between the discharge set or the charge set and the first set, that is, the fourth set can be a difference set between the discharge set and the first set, or a difference set between the charge set and the first set, depending on whether the system operates in the discharge mode or the charge mode.

[0065] The second set represents the set of battery packs that can continue to be connected in parallel, the third set represents the set of battery packs that need to be disconnected from the parallel connection, and the fourth set represents the set of battery packs that need to be connected in parallel.

[0066] See also Figure 8 In some embodiments, such as in the present embodiment, the method for supporting hot-swap parallel operation may include steps S180-S183.

[0067] S180, confirming whether the second set is an empty set;

[0068] S181, if the second set is an empty set, disconnecting the charging circuit of the third set and connecting the charging and discharging circuit of the fourth set;

[0069] S182, disconnecting the discharge circuit of the third set and confirming whether a new battery pack is added;

[0070] S183: If the second set is a non-empty set, disconnect the charge-discharge circuit of the third set, and connect the charge-discharge circuit of the fourth set.

[0071] In an embodiment of the present invention, steps S180-S183 are the discharge process when the system is in the discharge mode. In the discharge mode, the system confirms whether the second set is an empty set. If the second set is an empty set, the charging circuit of the third set is disconnected to prevent the battery packs in the fourth set from charging the battery packs in the third set after the charging and discharging circuit is turned on, so as to avoid the generation of circulating current. At this time, the discharge circuit of the battery packs in the third set is in the on state and can continuously supply power to the load. Then, the charging and discharging circuit of the fourth set is turned on, and the battery packs in the fourth set are added to the parallel queue. At this time, the battery packs in the fourth set and the third set supply power to the load at the same time. Then, the discharge circuit of the third set is disconnected, and it is confirmed whether a new battery pack has been added to the system. If so, all battery packs are re-divided into sets.

[0072] When the second set is not empty, that is, there are battery packs in the second set, the charge and discharge circuit of the third set is directly disconnected, and the second set supplies power to the load. Then the charge and discharge circuit of the fourth set is turned on, and the second and fourth sets supply power to the load at the same time. During the above discharge process, it is also continuously determined whether there are battery packs that meet the discharge conditions in the discharge waiting set. If there are, they are incorporated into the discharge set until the discharge waiting set is empty and the discharge ends.

[0073] See also Fig. 9 In some embodiments, such as in the present embodiment, the method for supporting hot-swap parallel operation may include steps S184-S187.

[0074] S184, confirming whether the second set is an empty set;

[0075] S185, if the second set is an empty set, disconnecting the discharge circuit of the third set and connecting the charge and discharge circuit of the fourth set;

[0076] S186, disconnecting the charging circuit of the third set and confirming whether a new battery pack is added;

[0077] S187: If the second set is a non-empty set, disconnect the charge-discharge circuit of the third set, and connect the charge-discharge circuit of the fourth set.

[0078] In an embodiment of the present invention, the process of the charging process is similar to the process of the discharging process, except that the battery packs in the set are not used to supply power to the load but are charged. In the charging mode, the system confirms whether the second set is an empty set. If the second set is an empty set, the discharge circuit of the third set is disconnected to prevent the battery packs in the third set from discharging the battery packs in the fourth set after the charging and discharging circuits of the battery packs in the fourth set are opened, thereby avoiding the generation of circulating currents. At this time, the charging circuit of the battery packs in the third set is in a conducting state, and charging can be continued. The charger will not have an abnormal no-load situation, and the charging efficiency can be improved. After that, the charging and discharging circuit of the fourth set is turned on, and the battery packs in the fourth set are added to the parallel queue. At this time, the battery packs in the fourth set and the third set are in a charging state. Then, the charging circuit of the third set is disconnected, and it is confirmed whether a new battery pack has been added to the system. If so, all battery packs are re-divided into sets.

[0079] When the second set is not empty, that is, there are battery packs in the second set, the charge-discharge circuit of the third set is directly disconnected, and the battery packs in the second set are in a charging state. Then the charge-discharge circuit of the fourth set is turned on, and the battery packs in the second and fourth sets are in a charging state at the same time. During the above charging process, it is also continuously determined whether there are battery packs that meet the charging conditions in the charging waiting set. If there are, they are incorporated into the charging set until the charging waiting set is empty and charging is completed.

[0080] The present invention further provides an energy storage system, which includes the hot-swap parallel support method described in any one of the above embodiments.

[0081] The hot-swappable parallel method and energy storage system disclosed in the present invention, when the system current is detected, controls the charging of the first preset set or controls the discharging of the second preset set according to the current type of the system current, and when a new battery pack is detected, re-divides the set to obtain a new first preset set and a new second preset set, so that the new battery pack can be connected in parallel while continuing to charge or discharge, thereby supporting hot-swappable parallel operation.

[0082] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for supporting hot-swap parallel operation, characterized in that: The method comprises: If the system current is detected, confirm the current type of the system current, and control the first preset set to charge or control the second preset set to discharge according to the current type of the system current, wherein the first preset set includes a charging set and a charging waiting set, and the second preset set includes a discharging set and a discharging waiting set, the battery packs in the charging set and the charging waiting set are used for charging, and the battery packs in the discharging set and the discharging waiting set are used for discharging; If a new battery pack is detected, the set is re-divided to obtain a new first preset set and a new second preset set.

2. The method according to claim 1, characterized in that The method further comprises: Calculating the voltages of all the battery packs to obtain a first target voltage and a second target voltage, wherein the first target voltage is a minimum voltage value among all the battery packs, and the second target voltage is a maximum voltage value among all the battery packs; All the battery packs are grouped and divided according to the first target voltage and the second target voltage.

3. The method according to claim 2, characterized in that The step of grouping all the battery packs according to the first target voltage and the second target voltage includes: Obtaining one of the battery packs from all the battery packs and setting it as a battery pack to be classified, and confirming the voltage of the battery pack to be classified; calculating a difference between the voltage of the battery pack to be classified and the first target voltage to obtain a first difference; If the first difference is less than a preset parallel threshold, the battery pack to be classified is merged into the charging set; If the first difference is greater than or equal to the preset parallel threshold, the battery pack to be classified is incorporated into the charging waiting set.

4. The method according to claim 3, characterized in that After the step of confirming the voltage of the battery pack to be classified, the method further includes: calculating a difference between the second target voltage and the voltage of the battery pack to be classified to obtain a second difference; If the second difference is less than the preset parallel threshold, the battery pack to be classified is merged into the discharge set; If the second difference is greater than or equal to the preset parallel threshold, the battery pack to be classified is incorporated into the discharge waiting set.

5. The method according to claim 1, characterized in that The step of controlling the charging of the first preset set according to the current type of the system current comprises: If the current type is a charging current, controlling the charging set to charge, and confirming whether there is a battery pack in the charging waiting set whose voltage meets a first preset condition; If there is a battery pack in the charging waiting set whose voltage meets the first preset condition, the battery pack meeting the first preset condition is incorporated into the charging set.

6. The method according to claim 1, characterized in that The step of controlling the discharge of the second preset set according to the current type of the system current comprises: If the current type is a discharge current, controlling the discharge set to discharge, and confirming whether there is a battery pack in the discharge waiting set whose voltage meets a second preset condition; If there is a battery pack in the discharge waiting set whose voltage satisfies the second preset condition, the battery pack that satisfies the second preset condition is incorporated into the discharge set.

7. The method according to claim 1, characterized in that The method further comprises: Acquire a set of battery packs connected in parallel last time to obtain a first set, and calculate an intersection of the first set and the discharge set or the charge set to obtain a second set; calculating a difference between the first set and the discharge set or the charge set to obtain a third set; A difference set between the discharge set or the charge set and the first set is calculated to obtain a fourth set.

8. The method according to claim 7, characterized in that The method further comprises: Determining whether the second set is an empty set; If the second set is an empty set, disconnecting the charging circuit of the third set and connecting the charging and discharging circuit of the fourth set; Disconnecting the discharge circuit of the third set and confirming whether a new battery pack is added; If the second set is a non-empty set, the charge-discharge loop of the third set is disconnected, and the charge-discharge loop of the fourth set is turned on.

9. The method according to claim 7, characterized in that The method further comprises: Determining whether the second set is an empty set; If the second set is an empty set, disconnecting the discharge circuit of the third set and connecting the charge and discharge circuit of the fourth set; Disconnect the charging circuit of the third set and confirm whether a new battery pack is added; If the second set is a non-empty set, the charge-discharge loop of the third set is disconnected, and the charge-discharge loop of the fourth set is turned on.

10. An energy storage system, characterized in that: The invention comprises a hot-swap parallel supporting method as described in any one of claims 1 to 9.

Images