Start control system and control method of iron-chromium flow battery and storage medium

Abstract

The invention belongs to the technical field of flow batteries, and particularly relates to a start control system and control method of an iron-chromium flow battery and a storage medium, the start control system comprises an iron-chromium flow battery unit, a storage battery, a storage battery management and control module, a storage battery circuit breaker and a DC-DC converter, the iron-chromium flow battery unit comprises a battery stack, and the battery stack is connected with the storage battery management and control module. The storage battery management and control module is used for management and control of the storage battery and is also used for on-off control of the storage battery circuit breaker, the storage battery circuit breaker is arranged between the storage battery and the DC-DC converter, and the output end of the DC-DC converter is electrically connected with the battery stack. By combining the external storage battery and the DC-DC converter, 0V starting of the iron-chromium flow battery can be realized, and it is ensured that the battery stack can be smoothly started and reaches a working state in a state without initial voltage.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid flow batteries, and in particular relates to a start-up control system, a control method and a storage medium of an iron-chromium liquid flow battery. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] As global energy demand continues to grow and environmental awareness increases, the development of clean, efficient and reliable energy storage technologies has become the forefront of scientific and technological development. Iron-chromium flow batteries are a new type of large-scale energy storage technology that uses chemical reactions between iron and chromium ions in an electrolyte to store and release energy. This technology has significant advantages in providing environmental protection and cost-effectiveness, and is particularly suitable for application scenarios such as grid regulation, renewable energy storage, and emergency power backup. Existing technologies such as lithium-ion batteries have problems such as short life and safety hazards, and it is difficult to meet the needs of future power systems. Liquid flow batteries, with their unique advantages, have become a strong competitor to solve this problem.

[0004] However, the iron-chromium flow battery needs to be pre-charged in multiple stages when there is no voltage in the battery stack to ensure that the flow battery stack reaches the optimal working state. The traditional startup method usually requires a bidirectional DC-DC converter to be connected in series between the PCS (energy storage converter) and the flow battery to pre-charge the battery to achieve the initial startup of the battery. Nevertheless, this traditional method has obvious limitations, especially in terms of system configuration and economic benefits.

[0005] When the battery stack voltage of the iron-chromium flow battery is higher than the preset minimum voltage, the use of a bidirectional DC-DC converter not only increases the complexity and cost of the system, but also after the battery is started, this device is usually no longer needed, which undoubtedly causes a waste of resources. In addition, in the long run, this pre-charging method may increase system losses and failure rates, affecting the operating efficiency and life of the battery. Therefore, although the bidirectional DC-DC converter can complete the pre-charging task, its single function and subsequent uselessness make it not the most economical or effective choice in certain application scenarios. In view of the above-mentioned defects, the present invention has made improvements. Summary of the invention

[0006] In order to overcome the shortcomings of the background technology, the present invention provides a starting control system, a control method and a storage medium for an iron-chromium liquid flow battery. The system can achieve 0V starting of the iron-chromium liquid flow battery by combining an external battery and a DC-DC converter, ensuring that the battery stack can be started smoothly and reach a working state without an initial voltage.

[0007] The technical solution adopted by the present invention is: a start-up control system for an iron-chromium liquid flow battery, comprising an iron-chromium liquid flow battery unit, a battery, a battery management and control module, a battery circuit breaker and a DC-DC converter. The iron-chromium liquid flow battery unit comprises a battery stack. The battery management and control module is used for the management and control of the battery and is also used for the on-off control of the battery circuit breaker. The battery circuit breaker is arranged between the battery and the DC-DC converter, and the output end of the DC-DC converter is electrically connected to the battery stack.

[0008] Further,

[0009] The battery circuit breaker arranged between the battery and the DC-DC converter includes a circuit breaker S1 and a circuit breaker S2, one end of the circuit breaker S1 is electrically connected to the battery, and the other end is electrically connected to one end of the circuit breaker S2, and the other end of the circuit breaker S2 is electrically connected to the input end of the DC-DC converter.

[0010] Further,

[0011] It also includes a DC-AC converter, and the iron-chromium liquid flow battery unit also includes a frequency converter and an electrolyte circulation pump. The battery circuit breaker is arranged between the battery and the DC-DC converter, and the battery circuit breaker includes a circuit breaker S3 and the circuit breaker S1. One end of the circuit breaker S3 is electrically connected between the circuit breaker S1 and the circuit breaker S2, and the other end is electrically connected to the input end of the DC-AC converter. The output end of the DC-AC converter is electrically connected to the input end of the frequency converter, and the output end of the frequency converter is electrically connected to the electrolyte circulation pump.

[0012] Further,

[0013] The output end of the battery stack is electrically connected to the input end of the inverter through a system line.

[0014] Further,

[0015] The output end of the DC-AC converter is connected to a filter, and the output end of the filter is electrically connected to the input end of the frequency converter.

[0016] Further,

[0017] It also includes an AC-DC converter, the battery circuit breaker is arranged between the battery and the AC-DC converter, and the battery circuit breaker includes a circuit breaker S4, the input end of the AC-DC converter is electrically connected to an external power supply, the output end of the AC-DC converter is electrically connected to one end of the circuit breaker S4, and the other end of the circuit breaker S4 is electrically connected to the battery.

[0018] The present invention also provides a 0V start-up control method for an iron-chromium liquid flow battery. Based on the above-mentioned start-up control system for the iron-chromium liquid flow battery, the method comprises:

[0019] Determine whether the conditions for 0V startup are met;

[0020] If the conditions for 0V startup are met, open the battery circuit breaker between the battery and the DC-DC converter and set the device parameters of the DC-DC converter;

[0021] Starting the DC-DC converter to perform 0V start-up charging on the battery stack of the iron-chromium liquid flow battery unit;

[0022] Check whether the battery stack voltage has completed 0V startup;

[0023] If it is detected that the battery stack voltage has completed 0V startup, the battery circuit breaker between the battery and the DC-DC converter is disconnected, otherwise charging continues.

[0024] The present invention also provides a black start control method for an iron-chromium liquid flow battery. Based on the above-mentioned start control system of the iron-chromium liquid flow battery, the method comprises:

[0025] Determine whether the conditions for black start are met;

[0026] If the conditions for black start are met, open the battery circuit breaker between the battery and the DC-AC converter and set the device parameters of the DC-AC converter;

[0027] The DC-AC converter is started to supply power to the inverter of the iron-chromium liquid flow battery unit, and the inverter is used to drive the electrolyte circulation pump of the iron-chromium liquid flow battery unit. The electrolyte circulation pump transports the positive and negative electrolytes to the battery stack through the pipeline to generate electricity.

[0028] Gradually increase the pumping frequency of the electrolyte circulation pump until it reaches the normal operating frequency;

[0029] When the pumping frequency of the electrolyte circulation pump reaches the normal operating frequency, the battery circuit breaker between the battery and the DC-AC converter is disconnected.

[0030] The present invention also provides a battery charging control method, based on the aforementioned iron-chromium liquid flow battery startup control system, the method comprising:

[0031] Determine whether the battery needs to be charged;

[0032] If the battery needs to be charged, set the device parameters of the AC-DC converter and open the battery circuit breaker between the AC-DC converter and the battery to start charging;

[0033] Check whether the battery is fully charged;

[0034] If it is detected that the battery charging is completed, the battery circuit breaker between the AC-DC converter and the battery is disconnected, otherwise charging continues.

[0035] The present invention also provides a computer-readable storage medium storing one or more programs, characterized in that when the one or more programs are executed, the aforementioned 0V startup control method of the iron-chromium liquid flow battery, or the aforementioned black start control method of the iron-chromium liquid flow battery, or the aforementioned battery charging control method can be implemented.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. It overcomes the limitations and shortcomings of the existing technology and provides a more efficient, economical and versatile 0V starting solution for the liquid flow battery system. By combining an external battery and a DC-DC converter, it can achieve 0V starting of the iron-chromium liquid flow battery, ensuring that the battery stack can be started smoothly and reach the working state without an initial voltage.

[0038] 2. By integrating the DC-AC converter, it not only supports the black start function of the iron-chromium flow battery, allowing the system to start autonomously in the event of a complete power outage, but also provides power for the iron-chromium flow battery auxiliary system when the system is powered off, enhancing the stability and reliability of the system.

[0039] 3. The flexibility and scalability of the iron-chromium flow battery system have been improved, and the 0V start and black start functions of the system have been realized through expansion modules; the modular design allows these key functions to be quickly deployed or removed as needed without interfering with other parts of the system, ensuring the integrity and stability of the system.

[0040] 4. The startup control system based on the iron-chromium flow battery provides corresponding control methods to ensure that the system can be accurately controlled according to different operating modes. These control methods further expand the application range of the iron-chromium flow battery and enhance its ability to adapt to various working conditions.

[0041] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings.

[0042] The present invention will be further described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0044] Figure 1 This is a schematic diagram of electrical wiring in a 0V start-up mode of a start-up control system of an iron-chromium liquid flow battery of the present invention;

[0045] Figure 2 This is a schematic diagram of electrical wiring in a black start mode of a start control system of an iron-chromium liquid flow battery of the present invention;

[0046] Figure 3 This is a schematic diagram of electrical wiring in the battery charging mode of the start-up control system of the iron-chromium liquid flow battery of the present invention;

[0047] Figure 4 A schematic flow chart of a battery charging control method of the present invention;

[0048] Figure 5 It is a schematic flow chart of a 0V startup control method of an iron-chromium liquid flow battery according to the present invention;

[0049] Figure 6 The present invention is a schematic flow chart of a black start control method for an iron-chromium liquid flow battery. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the implementation of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all 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.

[0051] like Figures 1 to 3 As shown, the present embodiment discloses a start-up control system for an iron-chromium liquid flow battery, comprising an iron-chromium liquid flow battery unit, a battery, a battery management and control module, a battery circuit breaker and a DC-DC converter. The iron-chromium liquid flow battery unit comprises a battery stack. The battery management and control module is used for the management and control of the battery, and is also used for the on-off control of the battery circuit breaker. The battery circuit breaker is arranged between the battery and the DC-DC converter, and the output end of the DC-DC converter is electrically connected to the battery stack.

[0052] The above technical solution can well realize the 0V start-up of the iron-chromium liquid flow battery system. It uses the electric energy of the battery to convert and control the voltage and current through the DC-DC converter, and outputs the voltage and current required by the battery stack in stages, providing the necessary initial electric energy for the iron-chromium liquid flow battery until the preset starting voltage is reached and the connection is disconnected.

[0053] In this embodiment, the battery (also referred to as the energy storage battery in this article) is the core energy storage unit of the system. The electric energy stored in the energy storage battery can be used to achieve 0V start and black start of the iron-chromium liquid flow battery stack, ensuring the independent operation of the system in the absence of external power supply or power grid failure.

[0054] In this embodiment, the battery management and control module is the intelligent center of the system, which is used for the management and control of the battery, responsible for monitoring the key parameters of the energy storage battery such as voltage, current and temperature, and controlling the charging and discharging process of the battery. In addition, the battery management and control module is also used for the on-off control of the battery circuit breaker, which can facilitate the battery charging and the 0V start and black start of the iron-chromium liquid flow battery stack. The battery management and control module also manages the circuit breaker inside the system to ensure that the power supply can be safely cut off or connected when necessary to protect the entire system from overload or short circuit.

[0055] In this embodiment, the DC-DC converter is used to convert the direct current released by the energy storage battery into the specific voltage and current required by the iron-chromium flow battery stack, which can facilitate the 0V start-up of the iron-chromium flow battery stack. This conversion process is crucial to ensure that the battery stack can operate stably under various working conditions.

[0056] In order to facilitate the functional expansion of the start-up control system of the iron-chromium liquid flow battery, the battery circuit breaker arranged between the battery and the DC-DC converter includes a circuit breaker S1 and a circuit breaker S2, one end of the circuit breaker S1 is electrically connected to the battery, and the other end is electrically connected to one end of the circuit breaker S2, and the other end of the circuit breaker S2 is electrically connected to the input end of the DC-DC converter.

[0057] In order to support the black start function of the iron-chromium flow battery, the start-up control system of the iron-chromium flow battery also includes a DC-AC converter, the iron-chromium flow battery unit also includes a frequency converter and an electrolyte circulation pump, the battery circuit breaker is provided between the battery and the DC-DC converter, and the battery circuit breaker includes a circuit breaker S3 and a circuit breaker S1, one end of the circuit breaker S3 is electrically connected between the circuit breaker S1 and the circuit breaker S2, and the other end is electrically connected to the input end of the DC-AC converter, the output end of the DC-AC converter is electrically connected to the input end of the frequency converter, and the output end of the frequency converter is electrically connected to the electrolyte circulation pump. In this embodiment, the battery releases electrical energy, and the DC-AC converter converts the direct current into the alternating current required by the frequency converter, thereby powering the electrolyte circulation pump (also referred to as the pump herein). The operation of the pump drives the electrolyte in the positive and negative electrode storage tanks to circulate and transport it to the battery stack to generate electrical energy. Subsequently, the generated electric energy will provide necessary power support for other equipment of the flow battery and the upper distribution lines. The system equipment will then supply electric energy to the inverter and pump to maintain operation, so that the electrolyte is transported to the battery stack to continuously generate electric energy. The frequency of the pump is gradually increased until the normal operating frequency is reached, and then the connection of the battery can be disconnected to complete the black start. The output end of the battery stack described in this embodiment is electrically connected to the input end of the inverter through the system line, which can facilitate the supply of electric energy generated by the battery stack to the inverter and pump to maintain operation. The DC-AC converter of this embodiment is used to convert the direct current of the battery into the alternating current required by the inverter of the iron-chromium liquid flow battery pump (i.e., the electrolyte circulation pump) to drive the battery pump and maintain the circulation of the electrolyte in the battery stack.

[0058] In some embodiments, the output end of the DC-AC converter is connected to a filter, and the output end of the filter is electrically connected to the input end of the frequency converter. In order to improve the quality of electric energy, this embodiment adds a filter to the output end of the DC-AC converter, and the filter smoothes the alternating current output by the DC-AC converter to remove unnecessary electrical signal interference. The battery converts the stored electric energy into alternating current through the DC-AC converter, and the alternating current is further processed by the filter to improve the quality of electric energy. When the system does not require 0V startup and black start, the output of the filter can be used as a backup power supply for the iron-chromium liquid flow battery system or other equipment in the field.

[0059] In order to facilitate charging the battery, the start-up control system of the iron-chromium liquid flow battery also includes an AC-DC converter, the battery circuit breaker is provided between the battery and the AC-DC converter, and the battery circuit breaker includes a circuit breaker S4, the input end of the AC-DC converter is electrically connected to the external power supply, the output end of the AC-DC converter is electrically connected to one end of the circuit breaker S4, and the other end of the circuit breaker S4 is electrically connected to the battery. In this embodiment, the AC-DC converter is used to convert an external AC power supply (i.e., an external power supply) into direct current to charge the energy storage battery. The energy storage battery of this embodiment stores the electric energy converted by the AC-DC converter, and the stored electric energy can then be used to achieve 0V startup and black start of the iron-chromium liquid flow battery stack, ensuring the independent operation of the system in the absence of an external power supply or a power grid failure.

[0060] In summary, the start-up control system of the iron-chromium liquid flow battery provided in the embodiment of the present invention not only realizes 0V start-up and black start of the battery system by integrating the above key components, but also optimizes the management and use of energy, and enhances the stability and reliability of the system.

[0061] The starting control system of the iron-chromium liquid flow battery in the embodiment of the present invention designs a set of 0V starting and black start expansion modules based on the iron-chromium liquid flow battery system, which is mainly used in the iron-chromium liquid flow battery energy storage system. By adopting this set of devices, not only the flexibility and scalability of the system are improved, but also the cost of the iron-chromium liquid flow battery system can be effectively reduced. It can be flexibly adjusted when there are changes in the future, without the need to be fixed to the initially installed equipment, providing more applicable energy solutions for different application fields and scenarios.

[0062] Based on the start-up control system of the iron-chromium liquid flow battery provided in the above embodiment, the embodiment of the present invention also provides a corresponding control method to ensure that the system can be accurately controlled according to different operating modes. The control method includes an iron-chromium liquid flow battery 0V start-up mode (i.e., an iron-chromium liquid flow battery 0V start-up control method), an iron-chromium liquid flow battery black start mode (i.e., an iron-chromium liquid flow battery black start control method) and a battery charging mode (i.e., a battery charging control method). Each of the above modes has detailed operating steps and control principles (monitoring mechanisms) to optimize system performance, ensure safe and stable operation, and improve energy utilization efficiency. These control methods further expand the application scope of iron-chromium liquid flow batteries and enhance their ability to adapt to various working conditions. Each control method will be further described below.

[0063] The present invention also provides a battery charging control method, based on the aforementioned iron-chromium liquid flow battery startup control system, the method comprising:

[0064] Determine whether the battery needs to be charged;

[0065] If the battery needs to be charged, set the device parameters of the AC-DC converter and open the battery circuit breaker between the AC-DC converter and the battery to start charging;

[0066] Check whether the battery is fully charged;

[0067] If it is detected that the battery charging is completed, the battery circuit breaker between the AC-DC converter and the battery is disconnected, otherwise charging continues.

[0068] Furthermore, if Figure 4 As shown, the specific operation steps of the above battery charging control method are as follows:

[0069] a. Operate the battery management and control module to perform system self-check to determine whether the battery needs to be charged;

[0070] b. Connect the AC-DC converter (also referred to as ACDC device in the figure) to an external power source;

[0071] c. Set AC-DC converter parameters;

[0072] d. Open the battery circuit breaker S4 between the battery and the AC-DC converter to start charging;

[0073] e. When the battery management and control module detects that the battery SOC is 100%, the circuit breaker S4 between the battery and the AC-DC converter is disconnected;

[0074] f. Complete battery charging mode.

[0075] In this embodiment, the control principle of the above battery charging control method is as follows:

[0076] Detect input power: confirm whether there is available input power (ie, external power) and convert it into direct current through an AC-DC device (ie, AC-DC converter).

[0077] Check battery status: Monitor the battery's SOC, health status and temperature through the battery management and control module to ensure it is suitable for charging.

[0078] Device self-test: Confirms that charging-related components are working properly to prevent malfunctions.

[0079] Start constant current charging: fast charge at a constant current until the voltage approaches the upper limit.

[0080] Monitor voltage: Monitor voltage in real time. If the upper limit is reached, the charging current will be reduced to prevent overvoltage.

[0081] Switch to constant voltage mode: maintain a stable voltage and reduce the charging current as the battery is gradually charged.

[0082] Current Decrease: The charging current is gradually reduced to the maintenance current level to optimize charging efficiency.

[0083] Determine the termination condition: terminate charging when the current drops to the minimum value or the SOC reaches 100% to prevent overcharging.

[0084] Feedback charging data: Record charging process data for easy monitoring and maintenance.

[0085] Abnormal protection: In case of abnormal conditions (such as sudden increase in current, sudden drop in voltage, excessive temperature), the power supply protection system will be immediately cut off.

[0086] Temperature compensation: automatically adjust charging parameters according to temperature to adapt to different environments.

[0087] Adaptive strategy: Intelligently adjust the charging strategy according to battery usage to extend battery life and maintain performance.

[0088] The present invention also provides a 0V start-up control method for an iron-chromium liquid flow battery. Based on the above-mentioned start-up control system for the iron-chromium liquid flow battery, the method comprises:

[0089] Determine whether the conditions for 0V startup are met;

[0090] If the conditions for 0V startup are met, open the battery circuit breaker between the battery and the DC-DC converter and set the device parameters of the DC-DC converter;

[0091] Starting the DC-DC converter to perform 0V start-up charging on the battery stack of the iron-chromium liquid flow battery unit;

[0092] Check whether the battery stack voltage has completed 0V startup;

[0093] If it is detected that the battery stack voltage has completed 0V startup, the battery circuit breaker between the battery and the DC-DC converter is disconnected, otherwise charging continues.

[0094] Furthermore, if Figure 5 As shown, the specific operation steps of the above-mentioned 0V start-up control method of the iron-chromium liquid flow battery are as follows:

[0095] a. Operate the battery management and control module to perform a system self-check to determine the current battery capacity (SOC) and whether it has enough energy to support the 0V starting process. If the battery capacity is insufficient, return to the aforementioned battery charging mode for charging;

[0096] b. Connecting a DC-DC device (i.e., a DC-DC converter, also abbreviated as a DCDC module or DCDC in the figure) to the positive and negative electrodes of the iron-chromium flow battery stack;

[0097] c. Operate the battery management and control module to open the battery circuit breakers S1 and S2 and set the device parameters of the DC-DC converter;

[0098] d. Start the DC-DC converter to charge the iron-chromium flow battery stack at 0V;

[0099] e. When the battery stack voltage is detected by the flow battery BMS system and the 0V startup is completed, the battery circuit breakers S1 and S2 are disconnected;

[0100] f. Complete the 0V start-up of the iron-chromium liquid flow battery.

[0101] In this embodiment, the control principle of the above-mentioned 0V startup control method of the iron-chromium liquid flow battery is as follows:

[0102] System self-check: Before starting, the battery management and control module will perform a comprehensive system self-check, including the detection of key components such as battery power, DC-DC converter, DC-AC converter and filter to ensure that they are all in normal working condition.

[0103] Battery state of charge assessment: Through the battery management and control module, the current charge (SOC) and health status of the battery are accurately measured to ensure that it has enough energy to support the 0V starting process.

[0104] Load assessment: The system will assess the type and size of the currently connected load, and adjust the startup strategy based on the load requirements to ensure a smooth startup.

[0105] Pre-start phase: At the beginning of the 0V startup phase, the system will slowly increase the voltage of the iron-chromium liquid flow battery stack through the DC-DC converter, while monitoring the rate of change of current and voltage to ensure that there is no impact on the battery stack.

[0106] Current control: As the battery stack voltage gradually increases, the control system will step-by-step adjust the output current of the DC-DC converter according to the voltage of the iron-chromium liquid flow battery stack to avoid battery damage caused by excessive or insufficient current.

[0107] Voltage monitoring and adjustment: The voltage across the battery stack is monitored in real time. Once the preset threshold is reached, the control system will adjust the output of the DC-DC converter to keep the voltage stable near the target value.

[0108] The present invention also provides a black start control method for an iron-chromium liquid flow battery. Based on the above-mentioned start control system of the iron-chromium liquid flow battery, the method comprises:

[0109] Determine whether the conditions for black start are met;

[0110] If the conditions for black start are met, open the battery circuit breaker between the battery and the DC-AC converter and set the device parameters of the DC-AC converter;

[0111] The DC-AC converter is started to supply power to the inverter of the iron-chromium liquid flow battery unit, and the inverter is used to drive the electrolyte circulation pump of the iron-chromium liquid flow battery unit. The electrolyte circulation pump transports the positive and negative electrolytes to the battery stack through the pipeline to generate electricity.

[0112] Gradually increase the pumping frequency of the electrolyte circulation pump until it reaches the normal operating frequency;

[0113] When the pumping frequency of the electrolyte circulation pump reaches the normal operating frequency, the battery circuit breaker between the battery and the DC-AC converter is disconnected.

[0114] Furthermore, if Figure 6 As shown, the specific operation steps of the above-mentioned iron-chromium liquid flow battery black start control method are as follows:

[0115] a. Operate the battery management and control module to perform a system self-check to determine the current battery capacity (SOC) and whether it has enough energy to support the black start process of the iron-chromium flow battery. If the battery capacity is insufficient, return to the aforementioned battery charging mode for charging;

[0116] b. Connect the output of the filter to the input of the iron-chromium flow battery inverter;

[0117] c. Operate the battery management and control module to open the battery circuit breakers S1 and S3, and set the device parameters of the DC-AC device (i.e., DC-AC converter, also abbreviated as DCAC module or DCAC in the figure);

[0118] d. Start the DC-AC converter to power the inverter;

[0119] e. The frequency converter starts the electrolyte circulation pump;

[0120] f. The electrolyte circulation pump transports the positive and negative electrolytes to the battery stack through pipelines to generate electricity. The electricity is transported to the upper power grid through the connection between the battery stack and other equipment, and continuously supplies power to the electrolyte circulation pump;

[0121] g. Gradually increase the pumping frequency of the electrolyte circulation pump until it reaches the normal operating frequency;

[0122] h. After the system runs stably (i.e. the pump frequency of the electrolyte circulation pump reaches the normal operating frequency), operate the battery management and control module to disconnect the battery circuit breakers S1 and S3;

[0123] i. Complete the black start mode of the iron-chromium liquid flow battery.

[0124] In this embodiment, the control principle of the above-mentioned iron-chromium liquid flow battery black start control method is as follows:

[0125] Energy reserve detection: First, operate the battery management and control module to perform a system self-test to check the power (SOC) and health status of the energy storage battery to ensure that it has enough energy to support the black start process.

[0126] Self-check of key components: The system will self-check key components such as DC-AC converter, filter and battery management and control module to ensure that they are in normal working condition.

[0127] Energy conversion and distribution: The DC power output by the battery is converted into the AC power required by the inverter through the DC-AC converter, and the power quality is improved through the filter before being input into the inverter.

[0128] Pump start: The inverter starts the electrolyte circulation pump through the frequency-converted AC power, and controls the electrolyte circulation pump to maintain the operation of the pump.

[0129] Generate electricity: The electrolyte circulation pump rotates to transport the electrolyte through the connecting pipe to the iron-chromium liquid flow battery stack, and the positive and negative electrolytes undergo redox reactions to generate electricity, which supplies power to other equipment in the energy storage system and the upper power grid.

[0130] Closed-loop energy cycle: The electrolyte circulation pump is then powered through the normal operation of the iron-chromium liquid flow battery system, and the pump frequency is gradually increased until it reaches the normal operating frequency, increasing the output of electrical energy and forming a closed-loop energy cycle.

[0131] Performance monitoring and adjustment: The battery stack is continuously monitored through the flow battery BMS system. The battery management and control module adjusts the control strategy based on real-time data to ensure that the system smoothly transitions to normal operation. When the system is running stably, disconnect the battery to complete the black start function of the iron-chromium flow battery.

[0132] It can be seen from this that the starting control system of the iron-chromium liquid flow battery in the embodiment of the present invention actually provides a set of iron-chromium liquid flow battery 0V starting and black start expansion modules, and provides a corresponding control method. The system device mainly uses batteries to realize the 0V starting and black start functions of the iron-chromium liquid flow battery system, and at the same time provides power energy for the iron-chromium liquid flow battery auxiliary system when the system is powered off.

[0133] The present invention improves the flexibility and scalability of the iron-chromium liquid flow battery system, and realizes the 0V start and black start functions of the system through the expansion module. The modular design allows these key functions to be quickly deployed or removed as needed without interfering with other parts of the system, ensuring the integrity and stability of the system. In actual application, these modules can be installed or removed according to actual needs, and only the cost of the currently required functions needs to be paid, thereby effectively reducing resource waste and providing an efficient, economical and adaptable energy solution for the entire system. In addition, as user needs change or technology develops, these modules can also be flexibly adjusted or upgraded to adapt to new needs or improve efficiency. This flexibility and scalability enables the iron-chromium liquid flow battery system to remain efficient and competitive in different application scenarios.

[0134] A key advantage of the present invention is its scalability and flexibility, so that even after the commissioning of the iron-chromium liquid flow battery system is completed, if the subsequent application no longer requires the 0V start or black start function, the device can be easily disassembled. This design significantly improves the economic benefits of the entire system, because users only need to pay for the functions that are currently required, and can flexibly adjust in the future when there are changes in demand, without being fixed to the initial installed equipment configuration.

[0135] In general, the iron-chromium liquid flow battery 0V start and black start expansion module designed by the present invention not only solves the problem of single use and long-term uselessness of traditional 0V start devices, but also improves the efficiency and economy of the entire iron-chromium liquid flow battery system. This will greatly improve the practicality and market competitiveness of liquid flow batteries in application scenarios such as grid regulation, renewable energy storage, and emergency power backup.

[0136] Based on the same inventive concept, the present invention also provides a computer-readable storage medium storing one or more programs, characterized in that when the one or more programs are executed, the aforementioned iron-chromium liquid flow battery 0V startup control method, or the aforementioned iron-chromium liquid flow battery black start control method, or the aforementioned battery charging control method can be implemented.

[0137] Parts not involved in this embodiment are the same as the prior art or can be implemented by using the prior art, and will not be further described here.

[0138] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A startup control system for an iron-chromium liquid flow battery, characterized in that: The invention comprises an iron-chromium liquid flow battery unit, a battery, a battery management and control module, a battery circuit breaker and a DC-DC converter. The iron-chromium liquid flow battery unit comprises a battery stack. The battery management and control module is used for managing and controlling the battery and for on-off control of the battery circuit breaker. The battery circuit breaker is arranged between the battery and the DC-DC converter. The output end of the DC-DC converter is electrically connected to the battery stack.

2. The start-up control system of an iron-chromium flow battery according to claim 1, characterized in that: The battery circuit breaker arranged between the battery and the DC-DC converter includes a circuit breaker S1 and a circuit breaker S2, one end of the circuit breaker S1 is electrically connected to the battery, and the other end is electrically connected to one end of the circuit breaker S2, and the other end of the circuit breaker S2 is electrically connected to the input end of the DC-DC converter.

3. The start-up control system of an iron-chromium liquid flow battery according to claim 2, characterized in that: It also includes a DC-AC converter, and the iron-chromium liquid flow battery unit also includes a frequency converter and an electrolyte circulation pump. The battery circuit breaker is arranged between the battery and the DC-DC converter, and the battery circuit breaker includes a circuit breaker S3 and the circuit breaker S1. One end of the circuit breaker S3 is electrically connected between the circuit breaker S1 and the circuit breaker S2, and the other end is electrically connected to the input end of the DC-AC converter. The output end of the DC-AC converter is electrically connected to the input end of the frequency converter, and the output end of the frequency converter is electrically connected to the electrolyte circulation pump.

4. The start-up control system of an iron-chromium flow battery according to claim 3, characterized in that: The output end of the battery stack is electrically connected to the input end of the inverter through a system line.

5. The start-up control system of an iron-chromium flow battery according to claim 3, characterized in that: The output end of the DC-AC converter is connected to a filter, and the output end of the filter is electrically connected to the input end of the frequency converter.

6. A start-up control system for an iron-chromium flow battery according to any one of claims 1 to 5, characterized in that: It also includes an AC-DC converter, the battery circuit breaker is arranged between the battery and the AC-DC converter, and the battery circuit breaker includes a circuit breaker S4, the input end of the AC-DC converter is electrically connected to an external power supply, the output end of the AC-DC converter is electrically connected to one end of the circuit breaker S4, and the other end of the circuit breaker S4 is electrically connected to the battery.

7. A 0V start-up control method for an iron-chromium liquid flow battery, based on the start-up control system of the iron-chromium liquid flow battery according to any one of claims 1 to 6, characterized in that: The method comprises: Determine whether the conditions for 0V startup are met; If the conditions for 0V startup are met, open the battery circuit breaker between the battery and the DC-DC converter and set the device parameters of the DC-DC converter; Starting the DC-DC converter to perform 0V start-up charging on the battery stack of the iron-chromium liquid flow battery unit; Check whether the battery stack voltage has completed 0V startup; If it is detected that the battery stack voltage has completed 0V startup, the battery circuit breaker between the battery and the DC-DC converter is disconnected, otherwise charging continues.

8. A black start control method for an iron-chromium liquid flow battery, based on the start-up control system of the iron-chromium liquid flow battery according to any one of claims 3 to 5, characterized in that: The method comprises: Determine whether the conditions for black start are met; If the conditions for black start are met, open the battery circuit breaker between the battery and the DC-AC converter and set the device parameters of the DC-AC converter; The DC-AC converter is started to supply power to the inverter of the iron-chromium liquid flow battery unit, and the inverter is used to drive the electrolyte circulation pump of the iron-chromium liquid flow battery unit. The electrolyte circulation pump transports the positive and negative electrolytes to the battery stack through the pipeline to generate electricity. Gradually increase the pumping frequency of the electrolyte circulation pump until it reaches the normal operating frequency; When the pumping frequency of the electrolyte circulation pump reaches the normal operating frequency, the battery circuit breaker between the battery and the DC-AC converter is disconnected.

9. A battery charging control method, based on the start-up control system of the iron-chromium liquid flow battery according to claim 6, characterized in that: The method comprises: Determine whether the battery needs to be charged; If the battery needs to be charged, set the device parameters of the AC-DC converter and open the battery circuit breaker between the AC-DC converter and the battery to start charging; Check whether the battery is fully charged; If it is detected that the battery charging is completed, the battery circuit breaker between the AC-DC converter and the battery is disconnected, otherwise charging continues.

10. A computer-readable storage medium storing one or more programs, characterized in that: When the one or more programs are executed, the 0V startup control method of the iron-chromium liquid flow battery described in claim 7 can be implemented, or the black start control method of the iron-chromium liquid flow battery described in claim 8 can be implemented, or the battery charging control method described in claim 9 can be implemented.

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