Online automatic maintenance method and system for sedimentary flow battery

Abstract

The invention discloses an online automatic maintenance method and system for a sedimentary flow battery, and the method comprises the steps: collecting the state information of a battery array module in real time according to a maintenance instruction of an upper computer, carrying out the analysis of the maintenance discharge operation of the battery array module according to the state information of the battery array module, dividing health levels, and generating operation parameters; and controlling the fault batteries to separate the formation through the operation parameters, and carrying out on-line automatic discharging on the fault batteries by utilizing a discharging load. By means of the method, online automatic maintenance of the sedimentary flow battery energy storage system can be achieved, shutdown is not needed, manual participation is not needed, normal operation of the system is not affected, and the maintenance cost of the system is greatly reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid flow batteries, and in particular relates to an online automatic maintenance method and system for a sedimentation type liquid flow battery. Background Art

[0002] A flow battery is an electrochemical energy storage device that uses two flowable electrolyte solutions to store energy. Unlike traditional batteries with fixed electrodes, the active materials of a flow battery are dissolved in an electrolyte solution, and these solutions can circulate between the storage tank and the battery stack. In the use of existing sedimentation-type flow battery energy storage systems, the health of the battery will decline over time. This is mainly because the chemical reaction of each battery in the system is not complete during the charging and discharging process, resulting in metal deposition on the electrode, making the battery power in the energy storage system unbalanced, the system performance declines, and the capacity decays, which seriously affects the normal use of the system. The current conventional maintenance method is to perform deep charge and discharge cycle control. Deep charge and discharge cycles can help remove deposits inside the battery, restore electrode activity, and improve battery performance and cycle life. However, the existing methods require the system to be shut down for maintenance, and most of them require manual maintenance, which has low maintenance efficiency, high cost, and affects the normal use of the system. Therefore, it is very necessary to perform online and automatic maintenance according to the status of the battery system to reduce the impact of the maintenance process. Summary of the invention

[0003] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a sedimentation type liquid flow battery online automatic maintenance method and system, which collects the status information of the battery array module in real time according to the maintenance instructions of the host computer, analyzes the maintenance and discharge operation of the battery array module according to the status information of the battery array module, divides the health level, and generates operating parameters; controls the separation of the faulty battery from the array through the operating parameters, and uses the discharge load to automatically discharge the faulty battery online. The method of the present invention can realize the online automatic maintenance of the sedimentation type liquid flow battery energy storage system, without the need for shutdown or manual participation, does not affect the normal operation of the system, and greatly reduces the cost of system maintenance.

[0004] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: An online automatic maintenance system for a sedimentation type liquid flow battery, comprising: a liquid flow battery energy storage system, an online bypass device, a discharge load, a SOC and SOH monitoring device, an integrated energy management system and a temporary power supply; The liquid flow battery energy storage system is a battery array module of various formations composed of a number of independent single liquid flow batteries arranged in series or in parallel; The online bypass device includes a single bypass switch corresponding to the number of single liquid flow batteries, each single bypass switch is connected to a single liquid flow battery, and the single liquid flow battery is connected or disconnected from the battery array module by controlling the opening and closing of the single bypass switch to change the array; Discharging load, connecting to the liquid flow battery energy storage system, discharging the single liquid flow battery or battery array module; The SOC and SOH monitoring device is connected to each single liquid flow battery of the liquid flow battery energy storage system, collects battery status information, and calculates the state of charge SOC value and health index value SOH of the single liquid flow battery and battery array module in real time; Temporary power supply, connected to the online bypass device, used to provide short-term power supply to the outside when the liquid flow battery energy storage system fails; The integrated energy management system is connected to the control interfaces of the above-mentioned electrical components through a control bus, and is used to analyze the current operating status of the battery through the state of charge and health index value SOH obtained by the SOC and SOH monitoring devices, realize the discharge maintenance control of the battery array module through the operating parameters, and coordinate the working status of the liquid flow battery energy storage system and the temporary power supply to realize online automatic maintenance.

[0005] The integrated energy management system comprises: The state acquisition module is used to collect the state detection information of the battery array module; connect to the SOC and SOH monitoring devices to collect the state of charge and health index value SOH; connect to the voltage detection channel of the discharge load to collect the voltage state information and discharge current state information of the battery array module; connect to the temperature sensor preset in the heat exchange device to read the electrolyte temperature state information; connect to the flow meter to collect the electrolyte flow rate; An analysis module is used to analyze the current operating state of the battery through the state of charge and health index value SOH obtained by the SOC and SOH monitoring device, and generate a discharge maintenance strategy; An operating parameter control module, configured to output operating parameters according to the discharge maintenance strategy to implement at least one of a plurality of discharge maintenance strategies of the battery array module; the plurality of discharge maintenance strategies include a sub-healthy discharge maintenance strategy, an unhealthy discharge maintenance strategy, and an extremely unhealthy discharge maintenance strategy; The communication module is used to send the status detection information of the battery array module and the operating parameters in the operating parameter control module to the host computer.

[0006] A method for online automatic maintenance of a sedimentation type liquid flow battery comprises the following steps: S1. The integrated energy management system receives maintenance instructions from the host computer and collects the state of charge (SOC) value and health index (SOH) value of the battery array module; S2. Perform online maintenance analysis of the flow battery array module according to the state of charge and health index value SOH of the battery array module, divide the health level, and generate discharge maintenance strategies corresponding to different health levels; the discharge maintenance strategies of different health levels include sub-healthy discharge maintenance strategy, unhealthy discharge maintenance strategy, and extremely unhealthy discharge maintenance strategy; S3. Controlling the online bypass device through operating parameters to change the formation of the battery array module, executing at least one of the discharge maintenance strategies with different health levels, and implementing the corresponding discharge maintenance process for the single liquid flow battery or the battery array module to the discharge load.

[0007] The online maintenance analysis of the battery array module includes: dividing the health level, obtaining the results of the discharge maintenance strategy corresponding to the different health levels, and generating the operating parameters of the corresponding discharge maintenance strategy.

[0008] The health level classification is a health level classified according to the percentage of the health index value SOH detected in real time by the SOC and SOH monitoring device, and is used to determine the discharge maintenance strategy belonging to a certain health level.

[0009] Furthermore, the sub-healthy discharge maintenance strategy is: When the battery is not working and is in a sub-healthy state, and the state of charge (SOC) value falls within the preset ratio range of the rated charge, it is judged to have entered a maintainable state; Output operating parameters and perform discharge maintenance process under maintainable state for sub-healthy batteries.

[0010] Furthermore, the unhealthy discharge maintenance strategy is: Intervene and limit the working status of the battery system so that it can reach a maintainable state in a shorter time; Control the battery to execute intervention mode. The integrated energy management system dispatches and controls the battery system to reduce charging or increase discharge, gradually entering a maintainable state. Output operating parameters and execute the discharge maintenance process in a maintainable state for unhealthy batteries.

[0011] Furthermore, the extremely unhealthy discharge maintenance strategy is: When the battery health is extremely unhealthy, execute the emergency maintenance state discharge maintenance process: The faulty liquid flow battery is separated through an online bypass device, and a temporary power source is connected to the working circuit to supply power externally; Output operating parameters, execute the discharge maintenance process in a maintainable state for extremely unhealthy batteries, and discharge the batteries rapidly at the maximum discharge current during the discharge process; After completing the deep discharge, the battery is connected to the array, the temporary power supply is separated, and normal charging and discharging work is resumed.

[0012] Furthermore, the discharge maintenance process in the maintainable state includes: The battery is disconnected from the overall formation by controlling the opening and closing of the single bypass switch in the online bypass device, so as to perform separate maintenance on it; Use a discharge load to deeply discharge the battery; When the discharge maintenance is completed and the battery system is in a state to be charged, it is connected to the battery array module through the single cell bypass switch in the online bypass device.

[0013] The present invention has the following beneficial effects and advantages:

[0014] 1. The present invention uses SOH and SOC as monitoring variables, and divides each battery into different health levels by judging the relationship between SOH and the health threshold, and then adopts different maintenance methods in a targeted manner.

[0015] 2. The present invention is combined with an online bypass device to separate the battery that needs maintenance from the system, so as not to affect the working status of the entire system and other batteries, thereby ensuring the safe and reliable operation of the entire system.

[0016] 3. Compared with the existing methods, the method of the present invention can realize online automatic maintenance of the sedimentation type liquid flow battery energy storage system, without stopping the system or manual participation, without affecting the normal operation of the system, and greatly reducing the cost of system maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a system framework diagram of the present invention.

[0018] Figure 2 This is a flow chart of online automatic maintenance of a sedimentation flow battery according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation method of the present invention is described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the invention, so the present invention is not limited to the specific implementation disclosed below. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0020] The embodiment of the present invention provides an online automatic maintenance method and system for sedimentation type liquid flow batteries, which collects the status information of the battery array module in real time according to the maintenance instructions of the host computer, analyzes the maintenance and discharge operation of the battery array module according to the status information of the battery array module, divides the health level, and generates operation parameters; controls the separation of the faulty battery from the array through the operation parameters, and uses the discharge load to automatically discharge the faulty battery online. The method of the present invention can realize the online automatic maintenance of the sedimentation type liquid flow battery energy storage system, without the need for shutdown or manual participation, without affecting the normal operation of the system, and greatly reducing the cost of system maintenance.

[0021] In the first aspect, an embodiment of the present invention provides an online automatic maintenance system for a sedimentation type liquid flow battery, the system mainly includes a liquid flow battery energy storage system, an online bypass device, a discharge load, a SOC and SOH monitoring device, an integrated energy management system and a temporary power supply, such as Figure 1 shown.

[0022] Liquid flow battery energy storage system is a battery array module with various formations composed of several independent single liquid flow batteries arranged in series or in parallel.

[0023] The online bypass device includes a single bypass switch corresponding to the number of single liquid flow batteries. Each single liquid flow battery is provided with a set of single bypass switches. By controlling the on and off of the single bypass switch, the single liquid flow battery can be freely removed from or reconnected to the battery array module.

[0024] Discharge load is used to achieve deep discharge of single liquid flow battery or battery array module.

[0025] The SOC and SOH monitoring device is connected to each single liquid flow battery in the liquid flow battery energy storage system, collects battery status information, and calculates the state of charge SOC value and health index value SOH of the single liquid flow battery and battery array module in real time.

[0026] The integrated energy management system is connected to the control interfaces of the above-mentioned electrical components through a control bus, and is used to analyze the current operating status of the battery through the state of charge and health index value SOH obtained by the SOC and SOH monitoring devices, realize the discharge maintenance control of the liquid flow battery energy storage system through operating parameters, and coordinate the working status of the liquid flow battery energy storage system and the temporary power supply to realize online automatic maintenance.

[0027] Temporary power supply, connected to the online bypass device, is used to provide short-term power supply to the outside when the liquid flow battery energy storage system fails.

[0028] Among them, in the integrated energy management system, the controller is controlled by PLC, or it can be controlled by a microprocessor (ARM or FPGA). The system mainly includes ARM microcontroller, storage chip, communication chip, AD sampling chip, clock chip and power management chip to realize the hardware circuit.

[0029] The status acquisition module is used to collect the status detection information of the battery array module; including: connecting to the SOC and SOH monitoring devices to collect the state of charge and health index value SOH; connecting to the voltage detection channel of the discharge load to collect the voltage status information and discharge current status information of the battery array module; connecting to the temperature sensor preset in the heat exchange device to read the electrolyte temperature status information; connecting to the flow meter to collect the electrolyte flow rate.

[0030] The analysis module is used to analyze the current operating state of the battery through the state of charge and health index value SOH obtained by the SOC and SOH monitoring device, and generate a discharge maintenance strategy and operating parameters.

[0031] The operating parameter control module is used to output operating parameters according to the discharge maintenance strategy to implement at least one of the multiple discharge maintenance strategies of the battery array module. The multiple discharge maintenance strategies include sub-healthy discharge maintenance strategy, unhealthy discharge maintenance strategy, and extremely unhealthy discharge maintenance strategy.

[0032] The communication module is used to send the status detection information of the battery array module and the operating parameters in the operating parameter control module to the host computer.

[0033] On the other hand, the embodiment of the present invention also provides an online automatic maintenance method for a sedimentation type liquid flow battery. The specific maintenance method is as follows: Figure 2 shown.

[0034] Step 1: Use the SOC and SOH monitoring device to collect the SOC (state of charge) and SOH (health) of the flow battery module in real time.

[0035] Step 2: According to the health index value SOH, the health level is divided into D level: SOH < 60%, extremely unhealthy; C level: 60% ≤ SOH < 80%, unhealthy; B level: 80% ≤ SOH < 90%, sub-healthy; A level: SOH ≥ 90%, healthy.

[0036] Step 3: Determine the health level based on the real-time SOH value and formulate the corresponding discharge maintenance strategy to be adopted.

[0037] Step 3-1: When it is detected that it belongs to Class A, the health level is determined to be healthy and no maintenance is required.

[0038] Step 3-2: When the condition is detected as Class B, the health level is judged to be sub-healthy and maintenance is required.

[0039] Step 3-3: When it is detected that it belongs to Class C, the health level is judged to be unhealthy and maintenance is required.

[0040] Step 3-4: When it is detected that it belongs to Class D, the health level is judged to be extremely unhealthy and maintenance is required.

[0041] Step 4: When the health level is detected as sub-healthy, the system needs to be maintained at an appropriate time.

[0042] Step 4-1: The timing of maintenance needs to be determined in combination with the SOC and the operating status of the flow battery energy storage system. When the SOC is at a low value, that is, SOC ≤ 30%, and the flow battery energy storage system is in a non-working state (neither charging nor discharging), it is judged to be in a maintainable state.

[0043] Step 4-2: The sub-healthy monomer flow battery is removed from the entire system by controlling the on / off of the monomer bypass switch in the online bypass device, and is maintained separately.

[0044] Step 4-3: Deeply discharge the sub-healthy single-cell liquid flow battery using a discharge load.

[0045] Step 4-4: When the maintenance is completed and the liquid flow battery energy storage system is in a state of waiting to be charged, it is connected back to the system through the single cell bypass switch in the online bypass device, so as not to affect the overall operation of the liquid flow battery energy storage system.

[0046] Step 5: When the health level is detected to be unhealthy, it is necessary to intervene and restrict the working state of the flow battery energy storage system so that it can reach a maintainable state in a shorter time.

[0047] Step 5-1: The battery enters the intervention mode. The integrated energy management system dispatches and controls the overall working status of the flow battery energy storage system, reduces the charging time and current of the flow battery energy storage system, or increases the discharge time and current, so that the flow battery energy storage system enters a maintainable state.

[0048] Step 5-2: Execute the process steps from step 4-2 to step 4-4 to remove the unhealthy single flow battery from the flow battery energy storage system, deeply discharge it, and reconnect it.

[0049] Step 6: When the health level is detected to be extremely unhealthy, the flow battery energy storage system needs to enter emergency maintenance status.

[0050] Step 6-1: Immediately supply power to the outside using a temporary power supply system through the integrated energy management system.

[0051] Step 6-2: Stop the operation of the flow battery energy storage system at the same time.

[0052] Step 6-3: By controlling the on and off of the single cell bypass switch in the online bypass device, the extremely unhealthy single cell flow battery is removed from the system, and by controlling the discharge load, the extremely unhealthy single cell flow battery is rapidly deeply discharged using the maximum discharge current.

[0053] Step 6-4: After the deep discharge is completed, the single cell bypass switch in the online bypass device is controlled to be connected back, and the temporary power supply is waited for to be finished. When the liquid flow battery energy storage system is about to enter the charging state, the liquid flow battery energy storage system is used to replace the temporary power supply and restore the normal working state.

[0054] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. An online automatic maintenance system for a sedimentation type liquid flow battery, characterized in that: include: Liquid flow battery energy storage system, online bypass device, discharge load, SOC and SOH monitoring device, integrated energy management system and temporary power supply; The liquid flow battery energy storage system is a battery array module of various formations composed of a number of independent single liquid flow batteries arranged in series or in parallel; The online bypass device includes a single bypass switch corresponding to the number of single liquid flow batteries, each single bypass switch is connected to a single liquid flow battery, and the single liquid flow battery is connected or disconnected from the battery array module by controlling the opening and closing of the single bypass switch to change the array; Discharging load, connecting to the liquid flow battery energy storage system, discharging the single liquid flow battery or battery array module; The SOC and SOH monitoring device is connected to each single liquid flow battery of the liquid flow battery energy storage system, collects battery status information, and calculates the state of charge SOC value and health index value SOH of the single liquid flow battery and battery array module in real time; Temporary power supply, connected to the online bypass device, used to provide short-term power supply to the outside when the liquid flow battery energy storage system fails; The integrated energy management system is connected to the control interfaces of the above-mentioned electrical components through a control bus, and is used to analyze the current operating status of the battery through the state of charge and health index value SOH obtained by the SOC and SOH monitoring devices, realize the discharge maintenance control of the liquid flow battery energy storage system through operating parameters, and coordinate the working status of the liquid flow battery energy storage system and the temporary power supply to realize online automatic maintenance.

2. The on-line automatic maintenance system for a sedimentation flow battery according to claim 1, characterized in that: The integrated energy management system comprises: The state acquisition module is used to collect the state detection information of the battery array module; including: connecting to the SOC and SOH monitoring devices to collect the state of charge and health index value SOH; connecting to the voltage detection channel of the discharge load to collect the voltage state information and discharge current state information of the battery array module; connecting to the temperature sensor preset in the heat exchange device to read the electrolyte temperature state information; connecting to the flow meter to collect the electrolyte flow rate; An analysis module is used to analyze the current operating state of the battery through the state of charge and health index value SOH obtained by the SOC and SOH monitoring device, and generate a discharge maintenance strategy; An operating parameter control module, configured to output operating parameters according to the discharge maintenance strategy to implement at least one of a plurality of discharge maintenance strategies of the battery array module; the plurality of discharge maintenance strategies include a sub-healthy discharge maintenance strategy, an unhealthy discharge maintenance strategy, and an extremely unhealthy discharge maintenance strategy; The communication module is used to send the status detection information of the battery array module and the operating parameters in the operating parameter control module to the host computer.

3. A method for online automatic maintenance of a sedimentation flow battery, characterized in that: The following steps are involved: S1. The integrated energy management system receives maintenance instructions from the host computer and collects the state of charge (SOC) value and health index (SOH) value of the battery array module; S2. Perform online maintenance analysis of the battery array module according to the state of charge and health index value SOH of the battery array module, divide the health level, and generate discharge maintenance strategies corresponding to different health levels; the discharge maintenance strategies of different health levels include sub-healthy discharge maintenance strategy, unhealthy discharge maintenance strategy, and extremely unhealthy discharge maintenance strategy; S3. Controlling the online bypass device through operating parameters to change the formation of the battery array module, executing at least one of the discharge maintenance strategies of different health levels, and realizing the corresponding discharge maintenance process of the single liquid flow battery or the battery array module to the discharge load.

4. The method for online automatic maintenance of a sedimentation flow battery according to claim 3, characterized in that: The online maintenance analysis of the battery array module includes: dividing the health level, obtaining the results of the discharge maintenance strategy corresponding to the different health levels, and generating the operating parameters of the corresponding discharge maintenance strategy.

5. The method for online automatic maintenance of a sedimentation flow battery according to claim 4, characterized in that: The health level classification is a health level classified according to the percentage of the health index value SOH detected in real time by the SOC and SOH monitoring device, and is used to determine the discharge maintenance strategy belonging to a certain health level.

6. The method for online automatic maintenance of a sedimentation flow battery according to claim 3, characterized in that: The sub-healthy discharge maintenance strategy is: When the battery is not working and is in a sub-healthy state, and the state of charge (SOC) value falls within the preset ratio range of the rated charge, it is judged to have entered a maintainable state; Output operating parameters and perform discharge maintenance process under maintainable state for sub-healthy batteries.

7. The method for online automatic maintenance of a sedimentation flow battery according to claim 3, characterized in that: The unhealthy discharge maintenance strategy is: Control the battery to execute intervention mode and gradually enter a maintainable state; Output operating parameters and execute the discharge maintenance process in a maintainable state for unhealthy batteries.

8. The method for online automatic maintenance of a sedimentation flow battery according to claim 3, characterized in that: The extremely unhealthy discharge maintenance strategy is: Separate the faulty flow battery and connect the temporary power supply to the working circuit to supply power to the outside, entering the emergency maintenance state; Perform emergency maintenance status discharge maintenance process.

9. An online automatic maintenance method for a sedimentation flow battery according to any one of claims 6 to 7, characterized in that: The discharge maintenance process in the maintainable state includes: The faulty battery is separated from the battery array module array and deeply discharged. After the discharge maintenance is completed, it is connected to the grid of the battery array module.

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