Online capacity checking device and method for storage battery

Abstract

The invention provides a storage battery online capacity checking device and method, and relates to the technical field of storage battery capacity checking, bidirectional flow of electric energy can be supported under different working conditions by adding a bidirectional AC / DC converter between a storage battery pack and an alternating current power grid which are connected in series, power can be supplied to a direct current bus from the alternating current power grid, and the storage battery online capacity checking device and method can be applied to storage batteries. In addition, electric energy in a direct-current bus can be fed back to an alternating-current power grid during capacity checking of the battery, the flexibility of the system is improved, hysteresis voltage control is adopted in the discharging process, the output current of the storage battery is kept unchanged, energy of the storage battery can be fully utilized, the capacity checking process is accelerated, and voltage fluctuation of the bus is reduced. Based on the scheme provided by the invention, online capacity checking can be realized, human intervention is reduced, and recycling of discharge electric energy is realized.

Description

Technical Field

[0001] The present application relates to the technical field of battery capacity verification, and in particular to a battery online capacity verification device and method. Background Art

[0002] In the prior art, when the battery capacity in the DC system of the substation is increased, it must be separated from the bus capacity, which requires a lot of manpower and wastes the energy stored in the battery during the increase in capacity. The battery can only be charged from the AC power grid. This one-way charging method limits the flexibility of power dispatching, especially during peak load periods, when the electric energy stored in the battery cannot be fed back to the AC power grid to achieve peak load reduction and valley filling, resulting in a certain amount of electric energy waste. In addition, during the increase in capacity process, the path is not adjusted according to the voltage fluctuation, and the voltage stability is not considered. Summary of the invention

[0003] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0004] To this end, the first purpose of this application is to provide an online battery capacity verification device.

[0005] The second objective of the present application is to provide a method for online capacity verification of a battery.

[0006] The third objective of the present application is to provide an electronic device.

[0007] A fourth objective of the present application is to provide a computer-readable storage medium.

[0008] A fifth object of the present application is to provide a computer program product.

[0009] To achieve the above-mentioned purpose, the first embodiment of the present application proposes a battery online capacity verification device, comprising: A DC bus, used to provide DC power to the load; at least one battery pack connected to the DC bus and used to supply power to the DC bus and loads during the capacity building process; A bidirectional AC / DC module, connected to the battery pack, for realizing bidirectional current conversion between the AC power grid, the battery pack and the DC bus; A first contactor, connected in series between the battery pack and the DC bus, for controlling the connection and disconnection between the battery pack and the DC bus; A second contactor, connected in series in the positive circuit of the battery pack, for controlling the connection between the battery pack and the bidirectional AC / DC module; A third contactor is connected in series in the negative electrode circuit of the battery pack and is used to control the connection between the bidirectional AC / DC module and the AC power grid; A control module is connected to the first contactor, the second contactor and the third contactor, and is used to control the opening and closing states of each contactor according to the voltage of the DC bus and the state of the battery, so as to dynamically adjust the discharge path of the battery pack.

[0010] Optionally, it also includes: a battery monitoring module, which is used to monitor the voltage of the DC bus, the discharge current of the battery pack, the voltage of the single cell in the battery pack, the internal resistance of the single cell and the temperature of the single cell.

[0011] Optionally, the control module is further used for: When the DC bus voltage is normal, controlling the first contactor to close so that the battery pack supplies power to the load alone; When the DC bus voltage is higher than a set maximum threshold, the second contactor and the third contactor are controlled to close, so that the battery pack supplies power to the DC bus and the AC grid at the same time; When the DC bus voltage is lower than a set minimum threshold, the bidirectional AC / DC module is controlled to supplement electric energy for the DC bus from the AC power grid through the third contactor, and supply power to the load together with the battery pack.

[0012] To achieve the above-mentioned purpose, a second aspect of the present application provides a method for online capacity verification of a battery, comprising: When a preset condition is met, the battery pack is started to be discharged to the DC bus at a constant current. Real-time detection of the DC bus voltage, and dynamic adjustment of the discharge path according to the fluctuation range of the DC bus voltage to ensure that the DC bus voltage is within a preset stable range; When the battery pack reaches the discharge capacity termination condition, controlling the battery pack to stop discharging; After the discharge is completed, the battery pack is charged with a constant current and voltage limit from the AC power grid through a bidirectional AC / DC module until the battery pack reaches a charging completion state.

[0013] Optionally, starting the battery pack capacity verification process when a preset condition is met includes: When the time from the last capacity check exceeds a preset period and the battery pack is in a normal state, the capacity check process of the battery pack is started.

[0014] Optionally, the real-time detection of the DC bus voltage and the dynamic adjustment of the discharge path according to the fluctuation range of the DC bus voltage to ensure that the DC bus voltage is within a preset stable range include: When the DC bus voltage Higher than the preset maximum threshold When the battery pack is controlled to discharge to the DC bus, the surplus electric energy is fed back to the AC grid through the bidirectional AC / DC module; When the DC bus voltage In When the current discharge path is kept unchanged, the battery pack is controlled to continue to supply power to the DC bus, but no power is fed back to the AC grid, wherein: is the hysteresis voltage; When the DC bus voltage exist When the battery pack is within the range, the battery pack is controlled to supply power only to the load; When the DC bus voltage Below the preset minimum threshold When the AC / DC module is in operation, the bidirectional AC / DC module is controlled to supply power from the AC power grid to the DC bus, and the bidirectional AC / DC module and the battery pack together supply power to the load.

[0015] Optionally, when the storage battery pack reaches a discharge capacity termination condition, controlling the storage battery pack to stop discharging includes: During the capacity verification process, the voltage of each single battery in the battery pack is monitored in real time. When the voltage of any single battery reaches a preset termination voltage, the contactor connected in parallel to the single battery is controlled to close to avoid over-discharge of the battery. When all the single cells in the battery pack reach the preset termination voltage, the discharge process is stopped and the discharge ends.

[0016] Optionally, the performing constant current and voltage-limited charging from the AC power grid to the battery pack through the bidirectional AC / DC module until the battery pack reaches a charging completion state includes: Converting the alternating current into direct current using a bidirectional AC / DC module to start charging the battery pack; During the charging process, the charging state of the battery pack is continuously monitored, and if the charging state is abnormal, the charging process is paused or exited; If the charging state is normal, check whether the battery pack meets the charging cut-off condition. When it is detected that the charging cut-off condition is met, stop the charging process and the charging process is completed.

[0017] To achieve the above-mentioned purpose, the third aspect of the present application provides an electronic device, including: a processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method as described in any one of the second aspects.

[0018] To achieve the above-mentioned purpose, the fourth aspect embodiment of the present application proposes a computer-readable storage medium, in which computer-readable storage medium is stored computer execution instructions, and when the computer execution instructions are executed by a processor, they are used to implement the method as described in any one of the second aspects.

[0019] To achieve the above-mentioned purpose, the fifth aspect of the present application proposes a computer program product, which implements any method in the second aspect when executed by a processor.

[0020] The technical solution provided by the embodiments of the present application brings at least the following beneficial effects: Through hysteresis voltage control, the device can cope with fluctuations in bus voltage and automatically adjust the discharge path to keep the bus voltage within a reasonable range, thereby avoiding frequent equipment switching and ensuring the stability of the device during the capacity-adding process; the use of bidirectional AC / DC modules not only meets the charging and discharging needs, but also simplifies the design of the control and communication systems, reduces the cost of system design and control, and achieves more flexible switching of charging and discharging paths; during the capacity-adding process, the device maintains a constant discharge current of the battery, and can maintain the accuracy of the capacity-adding process regardless of how the discharge path changes, avoiding the capacity-adding interruption problem caused by bus voltage loss, thereby significantly shortening the capacity-adding time and improving the capacity-adding efficiency.

[0021] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 A structural diagram of a battery online capacity verification device provided in an embodiment of the present application; Figure 2 A schematic diagram of a flow chart of a battery online capacity verification method provided in an embodiment of the present application; Figure 3 A schematic diagram of a method for online battery capacity verification provided in an embodiment of the present application Figure 4 A current diagram when the battery pack only supplies power to the load provided in the embodiment of the present application; Figure 5 A schematic diagram of current when the battery pack provides power to the load and the AC grid at the same time, as provided in an embodiment of the present application; Figure 6 A schematic diagram of current when a battery pack and an AC power grid jointly supply power to a load, provided in an embodiment of the present application; Figure 7A schematic diagram of the process of charging a battery pack provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0024] Traditional substation battery pack capacity test equipment and modes are time-consuming, high in labor costs, and cumbersome in process. The battery pack needs to be disconnected from the DC bus to be capacity checked, and an external discharge load is required when checking the battery pack capacity.

[0025] In order to solve this problem, the embodiment of the present application provides a battery online capacity-reducing device. By adding a bidirectional AC / DC converter between the series-connected battery group and the AC power grid, it can support the bidirectional flow of electric energy under different working conditions. It can not only supply power from the AC power grid to the DC bus, but also feed back the electric energy in the DC bus to the AC power grid when the battery is recharged, which increases the flexibility of the system. In the discharge process, hysteresis voltage control is adopted to keep the battery output current unchanged, so that the energy of the battery can be fully utilized, the capacity-reducing process is accelerated, and the bus voltage fluctuation is reduced. Based on the scheme proposed in this application, online capacity-reducing can be achieved, human intervention can be reduced, and the reuse of discharged electric energy can be realized.

[0026] Figure 1 This is a structural diagram of a battery online capacity verification device provided in an embodiment of the present application. Figure 1 As shown, the device includes: a DC bus, a battery pack, a bidirectional AC / DC module, a first contactor, a second contactor, a third contactor, a control module and a battery monitoring module.

[0027] In an embodiment of the present application, a DC bus is used to provide a DC power supply to a load; multiple battery packs are connected to the DC bus to supply power to the DC bus and the load during the core capacity process; a first contactor is connected in series between the battery pack and the DC bus to control the connection and disconnection of the battery pack and the DC bus; a second contactor is connected in series in the positive pole circuit of the battery pack to control the connection between the battery pack and the bidirectional AC / DC module; a third contactor is connected in series in the negative pole circuit of the battery pack to control the connection between the bidirectional AC / DC module and the AC power grid; the bidirectional AC / DC module is connected to the battery pack to realize bidirectional current conversion between the AC power grid, the battery pack and the DC bus.

[0028] In practical applications, multiple battery packs may be required according to load requirements, and the present application does not specifically limit the number of battery packs. Figure 1 In the illustrated embodiment, there are two battery packs in the device, namely, battery pack B1 and battery pack B2, which are used to supply power to the DC bus and the load during the core capacity process.

[0029] It is understandable that when there are multiple battery packs, there are also multiple corresponding bidirectional AC / DC modules. Figure 1 As shown, different bidirectional AC / DC modules are connected to battery pack B1 and battery pack B2 to realize bidirectional current conversion between the AC grid and the battery and DC bus, so as to feed the battery power back to the AC grid when the bus voltage is too high, or to supplement the DC bus with power from the AC grid when the bus voltage is too low.

[0030] Similarly, refer to Figure 1 The first contactors K21 and K22 are respectively connected in series between the battery group B1 and the battery group B2 and the DC bus, and are used to control the connection and disconnection of the battery group and the DC bus. The second contactors K31 and K32 are respectively connected in series in the positive circuits of the battery group B1 and the battery group B2, and are used to control the connection between the battery group and the bidirectional AC / DC module. The third contactors K41 and K42 are respectively connected in series in the negative circuits of the battery group B1 and the battery group B2, and are used to control the connection between the bidirectional AC / DC module and the AC power grid.

[0031] In addition, the device proposed in this application also includes a control module and a battery monitoring module.

[0032] Specifically, the control module is connected to contactors K21, K22, K31, K32, K41 and K42, and is used to control the opening and closing states of each contactor according to the voltage of the DC bus and the state of the battery, so as to dynamically adjust the discharge path of the battery and realize different power supply modes according to different bus voltage ranges.

[0033] In the embodiment of the present application, the control module has the following functions: When the DC bus voltage is normal, the contactor K21 or K22 is controlled to be closed, so that the battery pack supplies power to the load alone; when the DC bus voltage is higher than the set maximum threshold, the contactors K31 and K41 or the contactors K32 and K42 are controlled to be closed, so that the battery pack supplies power to the DC bus and the AC power grid at the same time; when the DC bus voltage is lower than the set minimum threshold, the bidirectional AC / DC module is controlled to supplement the DC bus with power from the AC power grid through the contactor K41 or K42, and supply power to the load together with the battery pack.

[0034] In the embodiment of the present application, the battery monitoring module is used to monitor the voltage of the DC bus, the discharge current of the battery pack, the voltage of the single cell in the battery pack, the internal resistance of the single cell and the temperature of the single cell.

[0035] Based on the battery online capacity verification device, this embodiment also provides a battery online capacity verification method. Figure 2 The flowchart of a battery online capacity verification method provided by the embodiment of the present application is as follows. Figure 2 As shown, the method may include the following steps: Step 101, when a preset condition is met, the battery pack capacity increase process is started, and the battery pack is controlled to discharge to the DC bus at a constant current.

[0036] In the embodiment of the present application, when the time from the last capacity check exceeds a preset period and the battery pack is in a normal state, the capacity check process of the battery pack is started.

[0037] Step 102 , detecting the DC bus voltage in real time, and dynamically adjusting the discharge path according to the fluctuation range of the DC bus voltage to ensure that the DC bus voltage is within a preset stable range.

[0038] In the present application, refer to Figure 2 When the capacity is increased, the control module controls the battery to discharge to the DC bus at a constant current and dynamically adjusts the discharge path according to the bus voltage fluctuation. , execute the following control strategy: 1. When the voltage is too high: When the DC bus voltage Higher than the preset maximum threshold When the power is off, the control module closes the second contactor and the third contactor, controlling the battery pack to not only discharge to the DC bus, but also feed back the excess electric energy to the AC grid through the bidirectional AC / DC module, so that the bus voltage drops to a stable range.

[0039] 2. When the voltage is close to the upper limit: When the DC bus voltage In When the current discharge path is kept unchanged, the battery pack is controlled to continue to supply power to the DC bus, but no power is fed back to the AC grid. is the hysteresis voltage.

[0040] 3. When the voltage is in the medium range: When the DC bus voltage exist When the voltage is within the specified range, the battery pack is controlled to supply power to the load only, keeping the DC bus voltage within a reasonable range while avoiding feeding power back to the AC grid.

[0041] 4. When the voltage is too low: When the DC bus voltage Below the preset minimum threshold When the AC / DC module is in a low voltage state, it controls the bidirectional AC / DC module to supply power from the AC grid to the DC bus, and together with the battery pack, supplies power to the load to compensate for the insufficient bus voltage and maintain a stable output.

[0042] It is understandable that It can be adjusted appropriately according to the actual operation conditions, which is related to the power of the load and the stability of the AC power grid. If the equipment is switched frequently, it can be appropriately increased. .and, and It can also be set according to the allowable fluctuation range of the busbar, and this application does not make any specific limitation on this.

[0043] It should be noted that when the battery pack is discharging, the current relationship of each branch will also change due to the change of the discharge path. , the current direction is Figure 4 As shown in the figure; when the DC bus voltage is high, the battery pack supplies power to the load and the AC grid at the same time. , the current direction is Figure 5 As shown in the figure; when the DC bus voltage is low, the battery and the AC grid jointly supply power to the load. , the current direction is Figure 6 shown.

[0044] Step 103, when the battery pack reaches the discharge capacity termination condition, the battery pack is controlled to stop discharging.

[0045] In the embodiment of the present application, a single battery cell of the series-connected battery pack is connected in parallel with a contactor.

[0046] During the capacity verification process, the voltage of each single cell in the battery pack is monitored in real time. When the voltage of any single cell reaches the preset termination voltage, the contactor connected in parallel to the single cell is controlled to close to avoid excessive discharge of the battery and to prevent premature discharge due to battery imbalance.

[0047] Finally, when all cells in the battery pack reach the preset termination voltage, the discharge process stops and the discharge ends.

[0048] Step 104, after the discharge is completed, the battery pack is charged with a constant current and voltage limit from the AC grid through the bidirectional AC / DC module until the battery pack reaches a charging completion state.

[0049] In the embodiment of the present application, after the battery has completed the core capacity discharge, it enters the charging stage. Reference Figure 7 ,First, start the charging process, use the bidirectional AC / DC module to convert AC power into DC power, and start charging the battery.

[0050] During the charging process, the system will continuously monitor the charging status to ensure that the charging is normal. If the charging status is normal, the system will continue to charge; if the charging status is abnormal (such as overheating, overcurrent, etc.), the system will pause or exit the charging process to avoid battery damage.

[0051] In addition, during the charging process, the system will continuously check whether the charging cut-off conditions are met. If the charging cut-off conditions are not met, the system will continue to charge and cycle detection. When it is detected that the charging cut-off conditions are met, the system stops the charging process, the charging process is completed, and the battery pack enters the floating charge or standby state.

[0052] In one embodiment of the present application, the charging cut-off conditions include the charging voltage or current reaching a set threshold, the battery state reaching a preset full charge state, etc., which are not specifically limited in the present application.

[0053] Based on the method proposed in this application, during the discharge process of the battery, although the discharge path may be adjusted with the bus voltage fluctuation, the output current always remains constant. This design ensures the continuity of the capacity testing process, avoids the interruption or repeated testing of the capacity testing caused by current fluctuations, and thus improves the accuracy of the capacity testing.

[0054] In order to verify the effect of the present application, a discharge test is also designed in the embodiment of the present application, and it is required to reach 80% of the rated capacity to be qualified.

[0055] The nuclear capacity test of traditional batteries is usually carried out at a rate of 10 hours. That is, if 80% full is used as the qualified judgment standard, the traditional 10-hour rate usually takes about 8 hours to complete the nuclear capacity test. However, the nuclear capacity method proposed in this application adopts a 3-hour rate, that is, if 80% full is used as the qualified judgment standard, it only takes 2.4 hours to complete the nuclear capacity test. Therefore, compared with the traditional method, the nuclear capacity test method of this application greatly shortens the test time, improves the test efficiency, and can reflect the technical effect of shortening the time.

[0056] In order to implement the above embodiments, the present application also proposes an electronic device, comprising: a processor, and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method provided by the above embodiments.

[0057] In order to implement the above embodiments, the present application also proposes a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the methods provided by the above embodiments.

[0058] In order to implement the above embodiments, the present application also proposes a computer program product, including a computer program, which implements the methods provided by the above embodiments when executed by a processor.

[0059] The collection, storage, use, processing, transmission, provision and disclosure of user personal information involved in this application are in compliance with relevant laws and regulations and do not violate public order and good morals.

[0060] It should be noted that personal information from users should be collected for legitimate and reasonable purposes and should not be shared or sold outside of these legitimate uses. In addition, such collection / sharing should be carried out after receiving the user's informed consent, including but not limited to notifying the user to read the user agreement / user notice and sign the agreement / authorization including authorization of relevant user information before the user uses the function. In addition, any necessary steps should be taken to protect and safeguard access to such personal information data and ensure that others who have access to personal information data comply with its privacy policy and procedures.

[0061] The present application is expected to provide an implementation scheme for users to selectively block the use or access of personal information data. That is, the present disclosure is expected to provide hardware and / or software to prevent or block access to such personal information data. Once the personal information data is no longer needed, the risk can be minimized by limiting data collection and deleting the data. In addition, when applicable, such personal information is de-identified to protect the privacy of the user.

[0062] In the description of the aforementioned embodiments, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they contradict each other.

[0063] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0064] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0065] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0066] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0067] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0068] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0069] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

[0070] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this application can be executed in parallel, sequentially or in different orders, as long as the expected results of the technical solution of this application can be achieved, and this document is not limited here.

[0071] The above specific implementations do not constitute a limitation on the protection scope of this application. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application should be included in the protection scope of this application.

Claims

1. A battery online capacity verification device, characterized in that: include: A DC bus, used to provide DC power to the load; at least one battery pack connected to the DC bus and used to supply power to the DC bus and loads during the capacity building process; A bidirectional AC / DC module, connected to the battery pack, for realizing bidirectional current conversion between the AC power grid, the battery pack and the DC bus; A first contactor, connected in series between the battery pack and the DC bus, for controlling the connection and disconnection between the battery pack and the DC bus; A second contactor, connected in series in the positive circuit of the battery pack, for controlling the connection between the battery pack and the bidirectional AC / DC module; A third contactor is connected in series in the negative electrode circuit of the battery pack and is used to control the connection between the bidirectional AC / DC module and the AC power grid; A control module is connected to the first contactor, the second contactor and the third contactor, and is used to control the opening and closing states of each contactor according to the voltage of the DC bus and the state of the battery, so as to dynamically adjust the discharge path of the battery pack.

2. The device according to claim 1, characterized in that Also includes: The battery monitoring module is used to monitor the voltage of the DC bus, the discharge current of the battery pack, the voltage of the single cell in the battery pack, the internal resistance of the single cell and the temperature of the single cell.

3. The device according to claim 1, characterized in that The control module is also used for: When the DC bus voltage is normal, controlling the first contactor to close so that the battery pack supplies power to the load alone; When the DC bus voltage is higher than a set maximum threshold, the second contactor and the third contactor are controlled to close, so that the battery pack supplies power to the DC bus and the AC grid at the same time; When the DC bus voltage is lower than a set minimum threshold, the bidirectional AC / DC module is controlled to supplement electric energy for the DC bus from the AC power grid through the third contactor, and supply power to the load together with the battery pack.

4. A method for online capacity checking of a battery, applied to the online capacity checking device of a battery as claimed in any one of claims 1 to 3, characterized in that: The following steps are involved: When a preset condition is met, the battery pack is started to be discharged to the DC bus at a constant current. Real-time detection of the DC bus voltage, and dynamic adjustment of the discharge path according to the fluctuation range of the DC bus voltage to ensure that the DC bus voltage is within a preset stable range; When the battery pack reaches the discharge capacity termination condition, controlling the battery pack to stop discharging; After the discharge is completed, the battery pack is charged with a constant current and voltage limit from the AC power grid through a bidirectional AC / DC module until the battery pack reaches a charging completion state.

5. The method according to claim 4, characterized in that The process of starting the battery pack capacity check when the preset conditions are met includes: When the time from the last capacity check exceeds a preset period and the battery pack is in a normal state, the capacity check process of the battery pack is started.

6. The method according to claim 5, characterized in that The real-time detection of the DC bus voltage and the dynamic adjustment of the discharge path according to the fluctuation range of the DC bus voltage to ensure that the DC bus voltage is within a preset stable range include: When the DC bus voltage Higher than the preset maximum threshold When the battery pack is controlled to discharge to the DC bus, the surplus electric energy is fed back to the AC grid through the bidirectional AC / DC module; When the DC bus voltage In When the current discharge path is kept unchanged, the battery pack is controlled to continue to supply power to the DC bus, but no power is fed back to the AC grid, wherein: is the hysteresis voltage; When the DC bus voltage exist When the battery pack is within the range, the battery pack is controlled to supply power only to the load; When the DC bus voltage Below the preset minimum threshold When the AC / DC module is in operation, the bidirectional AC / DC module is controlled to supply power from the AC power grid to the DC bus, and the bidirectional AC / DC module and the battery pack together supply power to the load.

7. The method according to claim 6, characterized in that When the storage battery pack reaches the discharge capacity termination condition, controlling the storage battery pack to stop discharging includes: During the capacity verification process, the voltage of each single battery in the battery pack is monitored in real time. When the voltage of any single battery reaches a preset termination voltage, the contactor connected in parallel to the single battery is controlled to close to avoid over-discharge of the battery. When all the single cells in the battery pack reach the preset termination voltage, the discharge process is stopped and the discharge ends.

8. The method according to claim 7, characterized in that The method of charging the battery pack with a constant current and voltage limit from the AC power grid through the bidirectional AC / DC module until the battery pack reaches a charging completion state includes: Converting the alternating current into direct current using a bidirectional AC / DC module to start charging the battery pack; During the charging process, the charging state of the battery pack is continuously monitored, and if the charging state is abnormal, the charging process is paused or exited; If the charging state is normal, check whether the battery pack meets the charging cut-off condition. When it is detected that the charging cut-off condition is met, stop the charging process and the charging process is completed.

9. An electronic device, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 4 to 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 4 to 8 when executed by a processor.

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