A method and system for controlling operating parameters of a vanadium redox flow battery system

Abstract

The application discloses a control method of operating parameters of a vanadium redox flow battery system, and comprises the following steps: constructing a hybrid model of the vanadium redox flow battery and constructing a power bond graph model of the vanadium redox flow battery; writing a system state equation according to the bond graph model, converting the system state equation into a corresponding mathematical model, and controlling and optimizing the output performance of the system according to parameters in the mathematical model. In the simulation analysis, the power bond graph model of the vanadium redox flow battery is converted into a corresponding block diagram model according to the power bond graph model; a dynamic simulation model of the vanadium redox flow battery system is established by combining the block diagram model and actual operating conditions of the system; corresponding parameter values in the bond graph model are obtained to obtain accurate output performance; the values of different parameters are changed to observe the change of the output performance, so that the influence of the values of different parameters on the output performance is determined. The application is more suitable for engineering application while realizing the control of the operating parameters of the whole system.

Description

Technical Field

[0001] This invention relates to the field of vanadium redox flow battery technology, and in particular to a method and control system for controlling the operating parameters of a vanadium redox flow battery system. Background Technology

[0002] The global energy structure is undergoing revolutionary changes, and my country's energy structure is also constantly being adjusted. The combination of energy storage and new energy sources is an inevitable trend in the development of power systems. Against this backdrop, flow batteries, as an energy storage technology with advantages such as safety, life-cycle capacity recovery, cycle life, system integration and scalability, overload capacity, and deep discharge capability, are gradually being promoted and used in the industry.

[0003] Currently available technologies control the battery system by controlling a specific parameter for a particular performance characteristic. These control strategies are biased towards one-to-one control, rather than a comprehensive approach to controlling the entire battery system. Examples include controlling temperature to prevent electrolyte crystal deposition, monitoring the battery's state of charge (SOC) to control charging and discharging, monitoring electrolyte temperature for heat exchange control, and monitoring vanadium ion concentration for battery status monitoring.

[0004] Due to the complexity and diversity of vanadium redox flow battery systems, which involve the coupling of multiple energy forms, traditional one-to-one control strategies can no longer meet the needs of the industry. Therefore, how to design a vanadium redox flow battery system that can more effectively handle multi-energy coupled systems and can comprehensively control the entire battery system has become a technical problem that needs to be solved by those in the field. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a solution that combines electrochemical models with hydraulic and mechanical models, which is a method for controlling the operating parameters of a vanadium redox flow battery system that is more suitable for engineering applications while achieving control of the operating parameters of the entire system.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] According to a first aspect of the present disclosure, a method for controlling the operating parameters of an all-vanadium redox flow battery system is provided, comprising the following steps:

[0008] Step 1: Construct a hybrid model corresponding to the actual vanadium redox flow battery system, so as to construct a power bond graph model of the vanadium redox flow battery system based on the hybrid model;

[0009] Step 2: Based on the bond graph theory analysis, the system state equation for evaluating the output performance of the all-vanadium redox flow battery system is obtained according to the power bond graph model. The system state equation is used to verify the effectiveness of the power bond graph model.

[0010] Step 3: Convert the verified valid power bond graph model into the corresponding block graph model;

[0011] Step 4: Combine the block diagram model with the actual operating conditions of the system to establish a dynamic simulation model of the all-vanadium redox flow battery system;

[0012] Step 5: Obtain the corresponding parameter values ​​in the power bond graph model by using the experimental data obtained from the dynamic simulation model and the bond graph theory, so as to obtain accurate output performance.

[0013] Step 6: Change the values ​​of different parameters to obtain the changes in output performance, and determine the correlation between the values ​​of different parameters and output performance based on the changes, so as to control the adjustment of operating parameters.

[0014] As a preferred technical solution, in step 1, the power bond graph model includes:

[0015] A flow source is the external input to the system.

[0016] The converter includes a pump and an electric stack;

[0017] Resistive components, including pumps, valves, pipelines, fuel cells, and testing instruments;

[0018] Capacitive elements, including electrolyte tanks and heat exchangers;

[0019] Inertial elements, including fuel cells;

[0020] The fuel cell stack inlet is connected to the pump via a heat exchanger, and the fuel cell stack outlet is connected to the pump via an electrolyte tank.

[0021] The pipeline connects converters, resistive components, capacitive components, and inertial components, excluding itself, together.

[0022] As a preferred technical solution, in step 2, based on the bond graph theory analysis, the system state equation for evaluating the output performance of the vanadium redox flow battery system is obtained according to the power bond graph model, specifically including the following steps:

[0023] Let the system variable X = [q5 q9 p15] T Input variable U = [Sf1 f17] T ,

[0024] The characteristic equations for each energy storage element are as follows:

[0025]

[0026] The characteristic equations for each resistive element are as follows:

[0027]

[0028] Based on the causal relationships and power flow direction within the power bond graph model, the relevant flow equations and potential equations are obtained as follows:

[0029]

[0030] Based on the power bond graph model, the relevant equivalent equations are obtained:

[0031]

[0032] Based on the relevant flow equation, potential equation, and relevant equivalent equations, the system state equation is obtained:

[0033]

[0034] set up

[0035] The system state equation is then obtained as follows:

[0036] In equations (1) to (5),

[0037] e(t) represents the potential variable;

[0038] f(t) represents the stream variable;

[0039] p(t) represents the power variable, which is equal to the scalar product of the potential variable and the current variable;

[0040] R(t) represents each resistive element, which includes pumps, valves, fuel cells, pipelines, and temperature testing instruments.

[0041] C(t) represents the energy storage element, which includes an electrolyte tank, a heat exchanger, and a fuel cell stack.

[0042] Where R3 is the energy loss of the pump, C5 is the energy change of the electrolyte in the electrolyte tank during outflow and inflow, R7 is the energy loss of valves and various instruments in the system, C9 is the energy change of the heat exchanger during temperature control, R11 is the energy loss of the pipeline in the system, R14 is the energy loss in the fuel cell stack, and I15 is the output electrical energy.

[0043] A second aspect of this disclosure provides a control system for an all-vanadium redox flow battery, characterized in that it includes:

[0044] The first model building unit is used to build a hybrid model corresponding to the actual vanadium redox flow battery system, so as to build a power bond graph model of the vanadium redox flow battery system based on the hybrid model;

[0045] The model transformation unit is used to analyze the system state equation obtained from the power bond graph model based on the bond graph theory to evaluate the output performance of the all-vanadium redox flow battery system. The system state equation is used to verify the effectiveness of the power bond graph model.

[0046] The second model building unit is used to convert the verified power bond graph model into the corresponding block graph model, and to establish a dynamic simulation model of the all-vanadium redox flow battery system by combining the block graph model and the actual operating conditions of the system.

[0047] The data processing unit is used to obtain the corresponding parameter values ​​in the bond graph model through the experimental data obtained from the dynamic simulation model and the bond graph theory, so as to obtain accurate output performance.

[0048] The control feedback unit is used to change the values ​​of different parameters to obtain the changes in output performance, and to determine the correlation between the values ​​of different parameters and output performance based on the changes, so as to control the adjustment of operating parameters.

[0049] As a preferred technical solution, the hybrid model includes:

[0050] Electrical control components control the start and stop of pumps, valves, and heat exchangers respectively;

[0051] Hydraulic components, including pumps, valves, heat exchangers, electrolyte tanks, and piping;

[0052] The fuel cell stack unit releases voltage and forms an electrolyte circulation circuit with the electrolyte tank via pumps, valves, and heat exchangers.

[0053] As a preferred technical solution, the electronic control component receives signals from each unit, and the signals from each unit specifically include:

[0054] The voltage signal transmitted by the pump;

[0055] The pump transmits pressure and flow signals;

[0056] Temperature and liquid level signals transmitted from the electrolyte tank;

[0057] Pressure and flow signals transmitted by valves and testing instruments;

[0058] The heat exchanger transmits pressure and flow signals;

[0059] Pressure and flow signals transmitted through pipelines;

[0060] Pressure and flow signals transmitted by the fuel cell stack;

[0061] The voltage signal transmitted by the fuel cell stack.

[0062] As a preferred technical solution, after receiving the signals transmitted by each unit, the electronic control component obtains the corresponding parameter values, and then changes the energy loss of each unit in the control system by changing the values ​​of different parameters, and finally obtains the changed parameter values.

[0063] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0064] 1. Based on the operation process and working principle of the physical model of the all-vanadium redox flow battery system, this application first establishes a power bond graph model of the all-vanadium redox flow battery system. Compared with other system dynamic analysis methods, the power bond graph model can handle systems with multiple energy forms coexisting in a unified way. At the same time, the bond graph model expressing the dynamic performance of the system has a simple structure and can intuitively reveal the interaction and energy conversion relationship between the components of the system, thus deepening the researcher's understanding of the system's dynamic structure.

[0065] 2. In the theoretical analysis of this application, the system state equation is written based on the established power bond graph model of the all-vanadium redox flow battery system. It can be transformed into the corresponding mathematical model. The mathematical model is used to describe and verify whether the established power bond graph model has practical significance. After the parameters in the mathematical model are confirmed, the output performance of the system can be controlled and optimized.

[0066] 3. This application obtains the corresponding parameter values ​​in the bond graph model through experimental data and bond graph theory, thus obtaining accurate output performance; and the influence on the output can be studied by changing the values ​​of different parameters.

[0067] 4. In this application, different vanadium redox flow battery systems can correspond to the same power bond graph model. The only difference is the parameter values ​​in the model. When conducting in-depth research, the specific operating parameters of the vanadium redox flow battery system can be controlled by changing a specific influencing factor, thereby achieving macroscopic control of the operating parameters of the vanadium redox flow battery system. Attached Figure Description

[0068] Figure 1 This is an overall schematic diagram of the all-vanadium redox flow battery system of the present invention;

[0069] Figure 2 This is the power bond graph model corresponding to the all-vanadium redox flow battery system of this invention;

[0070] Figure 3 This is the block diagram model corresponding to the all-vanadium redox flow battery system of the present invention;

[0071] Figure 4 This is a dynamic simulation model of the all-vanadium redox flow battery system of the present invention;

[0072] Figure 5 This is a diagram showing the correspondence between bonded primitives and block graph units. Detailed Implementation

[0073] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0074] Example 1: As Figures 1 to 5 As shown, the first aspect of this invention provides a method for controlling the operating parameters of an all-vanadium redox flow battery system, comprising the following steps:

[0075] Step 1: Construct a hybrid model corresponding to the actual vanadium redox flow battery system, so as to construct a power bond graph model of the vanadium redox flow battery system based on the hybrid model.

[0076] Specifically, this hybrid model is used to represent the specific system configuration of a real vanadium redox flow battery system, that is, to digitize the actual vanadium redox flow battery system data to serve as the basis for subsequent data processing; such as Figure 2 As shown, Figure 2 A specific example of a power bond graph model is shown, which includes: a flow source, representing external input to the system; a converter, including a pump and a fuel cell stack; resistive elements, including a pump, valves, piping, the fuel cell stack, and testing instruments; capacitive elements, including an electrolyte tank and a heat exchanger; and inertial elements, including the fuel cell stack. The fuel cell stack's inlet is connected to the pump via a heat exchanger, and its outlet is connected to the pump via an electrolyte tank. Piping connects the converter, resistive elements, capacitive elements, and inertial elements together, excluding itself.

[0077] In some specific examples, the flow source includes the power to drive the pump and the energy input of the heat exchange medium in the heat exchanger; the pump is both a converter, converting electrical energy into mechanical energy to drive the electrolyte circulation, and a resistive element, which has its own energy loss; one end of the pump is connected to the electrolyte tank and the other end to the heat exchanger; the electrolyte tank, as a capacitive element, is used to store energy; one end of the electrolyte tank is connected to the pump and the other end to the fuel cell outlet; the valve, as a resistive element, has energy loss during operation; the valve is installed in the pipeline to control the electrolyte operating flow rate and pressure, as well as protection measures. The heat exchanger, as a capacitive element, is where the temperature of the reacted electrolyte is controlled while a portion remains. One end of the heat exchanger is connected to the pump, and the other end is connected to the inlet of the fuel cell stack. The piping, as a resistive element, has energy losses and connects the other components of the system as a whole. The fuel cell stack is both a converter, converting chemical energy into electrical energy and outputting it, and a resistive element, which has energy losses when the temperature changes. Its inlet is connected to the heat exchanger, and its outlet is connected to the inlet of the electrolyte tank. The temperature measuring instrument is a resistive element, and here it is classified with the valve, and it has energy consumption.

[0078] It should be noted that the relevant theory of bond graphs is as follows: Based on the fundamental principle of energy conservation, a system is represented by a set of basic components connected in a specific way using prescribed symbols; this is called a system bond graph. A bond graph is a unified and intuitive graphical representation of the system's dynamic performance. The basic components that constitute it are called bond primitives, and the lines connecting bond primitives represent the flow of power, called bonds. A bond connects two bond primitives. No energy flows at the unbonded openings, but the bonds are used to transfer power. This type of power-transferring bond is called a power bond. There is another type of bond that connects two bond primitives, but it does not transfer power; it only transmits signals. Therefore, this type of bond is called a signal bond. A power bond has a half-arrow symbol at one end, while a signal bond has a full arrow symbol. The connection between bond primitives connected by a bond is called a bonding. When bond primitives are bonded, there is no energy loss at the bond during the transfer of energy from one bond primitive to another.

[0079] Bond graph theory unifies various physical parameters into four generalized variables: potential variables, current variables, generalized momentum, and generalized displacement. The scalar product of the potential variable e(t) and the current variable f(t) is called power P(t), hence the potential variable and current variable are also called power variables. Generalized momentum p(t) is defined as the time integral of the potential variable, and generalized displacement q(t) is defined as the time integral of the current variable; therefore, generalized momentum and generalized displacement are energy variables. Different systems, such as mechanical systems, electrical systems, and hydraulic systems, each have corresponding generalized variables. Thus, bond graphs can represent different types of systems using the same type of variable.

[0080] The basic bond graph primitives in bond graph theory include resistive element R (describing the power loss of the system), capacitive element C (describing the physical effects of potential and generalized displacement), inertial element I (describing the physical effects of flux and generalized momentum), potential source Se (describing the effect of the environment on the system potential), current source Sf (describing the effect of the environment on the system current), converter TF (a component describing the energy conversion of the system), common potential junction (0-junction, used to connect potential variables with the same energy form and equal value in the relevant physical effects of the system), and common current junction (1-junction, used to connect flux variables with the same energy form and equal value in the relevant physical effects or components of the system).

[0081] Step 2: Based on the bond graph theory analysis, the system state equation for evaluating the output performance of the all-vanadium redox flow battery system is obtained according to the power bond graph model. The system state equation is used to verify the effectiveness of the power bond graph model.

[0082] Specifically, the system state equation can be written based on the power bond graph and processed by converting it into a mathematical model. This data model can describe and verify whether the established power bond graph model has practical significance. By inputting relevant parameters and performing calculations, it can be determined whether the power bond graph model has practical significance. If it is determined to be meaningful, it means that the power bond graph model is effective. Once the parameters in the mathematical model are finally confirmed, the output performance of the system can be controlled and optimized.

[0083] It should be noted that different vanadium redox flow battery systems correspond to the same power bond graph model. The only difference is that the parameter values ​​in the model are different. When conducting in-depth research, the specific operating parameters of the vanadium redox flow battery system can be controlled by changing a specific influencing factor, thereby achieving macroscopic control of the operating parameters of the vanadium redox flow battery system.

[0084] The process of obtaining the system state equation for evaluating the output performance of the vanadium redox flow battery system based on the power bond graph theory analysis includes the following steps:

[0085] Let the system variable X = [q5 q9 p15] T Input variable U = [Sf1 f17] T ,

[0086] The characteristic equations for each energy storage element are as follows:

[0087]

[0088] The characteristic equations for each resistive element are as follows:

[0089]

[0090] Based on the causal relationships and power flow direction within the power bond graph model, the relevant flow equations and potential equations are obtained as follows:

[0091]

[0092] Based on the power bond graph model, the relevant equivalent equations are obtained:

[0093]

[0094] Based on the relevant flow equation, potential equation, and relevant equivalent equations, the system state equation is obtained:

[0095]

[0096] set up

[0097] The system state equation is then obtained as follows:

[0098] In equations (1) to (5),

[0099] e(t) represents the potential variable;

[0100] f(t) represents the stream variable;

[0101] p(t) represents the power variable, which is equal to the scalar product of the potential variable and the current variable;

[0102] R(t) represents each resistive element, which includes pumps, valves, fuel cells, pipelines, and temperature testing instruments.

[0103] C(t) represents the energy storage element, which includes an electrolyte tank, a heat exchanger, and a fuel cell stack.

[0104] Where R3 is the energy loss of the pump, C5 is the energy change of the electrolyte in the electrolyte tank during outflow and inflow, R7 is the energy loss of valves and various instruments in the system, C9 is the energy change of the heat exchanger during temperature control, R11 is the energy loss of the pipeline in the system, R14 is the energy loss in the fuel cell stack, and I15 is the output electrical energy.

[0105] Step 3: Transform the verified power bond graph model into the corresponding block graph model. The block graph model is a representation of the system schematic diagram, which can be converted into the mathematical model of the system through methods such as Laplace transform for further theoretical analysis and calculation.

[0106] Step 4: Combining the block diagram model and the actual operating conditions of the system, establish a dynamic simulation model of the all-vanadium redox flow battery system. This dynamic simulation model is as follows: Figure 4 As shown.

[0107] Step 5: Obtain the corresponding parameter values ​​in the bond graph model by using the experimental data obtained from the dynamic simulation model and the bond graph theory, so as to obtain accurate output performance.

[0108] Step 6: Change the values ​​of different parameters to obtain the changes in output performance, and determine the correlation between the values ​​of different parameters and output performance based on the changes, so as to control the adjustment of operating parameters; specifically, this step is used to determine the optimal parameters of the mathematical model in step 2, so as to control and optimize the output performance of the system.

[0109] Example 2: A second aspect of this invention provides a control system for a vanadium redox flow battery, comprising: a first model building unit for building a hybrid model corresponding to an actual vanadium redox flow battery system, used to build a power bond graph model of the vanadium redox flow battery system based on the hybrid model; a model conversion unit for analyzing the system state equation obtained from the power bond graph model based on bond graph theory, used to evaluate the output performance of the vanadium redox flow battery system, the system state equation being used to verify the effectiveness of the power bond graph model; a second model building unit for converting the verified effective power bond graph model into a corresponding block graph model, and establishing a dynamic simulation model of the vanadium redox flow battery system by combining the block graph model and the actual operating conditions of the system; a data processing unit for obtaining the corresponding parameter values ​​in the bond graph model through experimental data obtained from the dynamic simulation model and bond graph theory, so as to obtain accurate output performance; and a control feedback unit for changing the values ​​of different parameters to obtain the changes in output performance, and determining the correlation between the values ​​of different parameters and output performance based on the changes, so as to control the adjustment of operating parameters.

[0110] The hybrid model can be derived from the all-vanadium redox flow battery system, including:

[0111] Control components, including elements that control the start and stop of pumps, valves, and heat exchangers;

[0112] Hydraulic components, including pumps, valves, heat exchangers, pipelines, etc. in the system;

[0113] The fuel cell stack unit releases voltage and forms an electrolyte circulation circuit with the electrolyte tank via pumps, valves, and heat exchangers.

[0114] The electronic control unit receives signals from each unit, and the signals from each unit specifically include:

[0115] The voltage signal transmitted by the pump;

[0116] The pump transmits pressure and flow signals;

[0117] Temperature and liquid level signals transmitted from the electrolyte tank;

[0118] Pressure and flow signals transmitted by valves and instruments;

[0119] The heat exchanger transmits pressure and flow signals;

[0120] Pressure and flow signals transmitted through pipelines;

[0121] Pressure and flow signals transmitted by the fuel cell stack;

[0122] The voltage signal transmitted by the fuel cell stack; after receiving the signals transmitted by each unit, the electronic control component obtains the corresponding parameter values, and then changes the energy loss of each unit in the control system by changing the values ​​of different parameters, and finally obtains the changed parameter values.

[0123] This invention establishes a power bond graph model of a vanadium redox flow battery system based on its physical model, working principle, and operation process. Compared with other system dynamics analysis methods, the power bond graph model can handle systems with multiple energy states in a unified way. Furthermore, the bond graph model, which expresses the dynamic performance of the system, has a simple structure and can intuitively reveal the interactions and energy conversion relationships between the components of the system. By obtaining the corresponding parameter values ​​in the bond graph model through experimental data and bond graph theory, accurate output performance can be obtained. The impact of changing different parameter values ​​on the output can be studied. Different vanadium redox flow battery systems can correspond to the same power bond graph model; the only difference is the parameter values ​​in the model. In in-depth research, by changing a specific influencing factor, the operating parameters of the specific vanadium redox flow battery system can be controlled, thereby achieving macroscopic control of the operating parameters of the vanadium redox flow battery system.

[0124] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention. These are all equivalent modifications and improvements made to the above embodiments based on the essential technology of the present invention, and all of these fall within the protection scope of the present invention.

Claims

1. A method for controlling the operating parameters of an all-vanadium redox flow battery system, characterized in that, Includes the following steps: Step 1: Construct a hybrid model corresponding to the actual vanadium redox flow battery system. This hybrid model is used to represent the specific system composition of the actual vanadium redox flow battery system and digitize the actual vanadium redox flow battery system data to serve as the basis for subsequent data processing. Based on this hybrid model, and based on the operation process and working principle of the physical model of the vanadium redox flow battery system, establish a power bond graph model of the vanadium redox flow battery system. Step 2: Based on the bond graph theory analysis, the system state equation for evaluating the output performance of the all-vanadium redox flow battery system is obtained according to the power bond graph model. The system state equation is used to verify the effectiveness of the power bond graph model. Step 3: Convert the verified valid power bond graph model into the corresponding block graph model; Step 4: Combine the block diagram model with the actual operating conditions of the system to establish a dynamic simulation model of the all-vanadium redox flow battery system; Step 5: Obtain the corresponding parameter values ​​in the power bond graph model by using the experimental data obtained from the dynamic simulation model and the bond graph theory, so as to obtain accurate output performance; Step 6: Change the values ​​of different parameters to obtain the changes in output performance, and determine the correlation between the values ​​of different parameters and output performance based on the changes, so as to control the adjustment of operating parameters.

2. The method for controlling the operating parameters of the all-vanadium redox flow battery system according to claim 1, characterized in that, In step 1, the bond graph model includes: A flow source is the external input to the system. The converter includes a pump and an electric stack; Resistive components include pumps, valves, pipelines, fuel cells, and testing instruments; Capacitive elements, including electrolyte tanks and heat exchangers; Inertial elements, including fuel cells; The fuel cell stack inlet is connected to the pump via a heat exchanger, and the fuel cell stack outlet is connected to the pump via an electrolyte tank. The pipeline connects converters, resistive components, capacitive components, and inertial components, excluding itself, together.

3. The method for controlling the operating parameters of the all-vanadium redox flow battery system according to claim 2, characterized in that, In step 2, based on the bond graph theory analysis, the system state equation for evaluating the output performance of the all-vanadium redox flow battery system is obtained according to the power bond graph model. This specifically includes the following steps: Let the system variable X = [q5 q9 p15] T Input variable U = [Sf1 f17] T , The characteristic equations for each energy storage element are as follows: The characteristic equations for each resistive element are as follows: Based on the causal relationships and power flow direction within the power bond graph model, the relevant flow equations and potential equations are obtained as follows: Based on the power bond graph model, the relevant equivalent equations are obtained: Based on the relevant flow equation, potential equation, and relevant equivalent equations, the system state equation is obtained: set up The system state equation is then obtained as follows: In equations (1) to (5), e(t) represents the potential variable; f(t) represents the stream variable; p(t) represents the power variable, which is equal to the scalar product of the potential variable and the current variable; q(t) represents the generalized displacement, defined as the time integral of the flow variable; R(t) represents each resistive element, which includes pumps, valves, fuel cells, pipelines, and temperature testing instruments. C(t) represents the energy storage element, which includes an electrolyte tank, a heat exchanger, and a fuel cell stack. Sf represents the flow source, describing the effect of the environment on the system flow; Where R3 is the pump's energy loss, f3 represents the flow rate of R3, and e3 represents the potential rate of R3; C5 is the energy change of the electrolyte in the electrolyte tank during outflow and inflow, f5 is the potential variable of C5, e5 is the flow variable of C5, and q5 is the generalized displacement of C5 in the electrolyte tank. R7 is the energy loss of valves and various instruments in the system, f7 is the flow variable of R7, and e7 is the potential variable of R7. C9 is the energy change of the heat exchanger when it is controlling the temperature, f9 is the potential variable of C9, e9 is the flow variable of C9, and q9 is the generalized displacement of C9 of the heat exchanger. R11 is the energy loss of the pipeline in the system, f11 is the flow variable of R11, and e11 is the potential variable of R11. R14 is the energy loss in the fuel cell stack, f14 is the current flow of R14, and e14 is the potential flow of R14. I15 is the output electrical energy, f15 is the flow variable of I15, and p15 is the generalized momentum of the output I15.

4. A control system for an all-vanadium redox flow battery, characterized in that, include: The first model building unit is used to build a hybrid model corresponding to the actual vanadium redox flow battery system. This hybrid model is used to represent the specific system composition of the actual vanadium redox flow battery system and to digitize the actual vanadium redox flow battery system data to serve as the basis for subsequent data processing. Based on this hybrid model, and on the basis of the operation process and working principle of the physical model of the vanadium redox flow battery system, a power bond graph model of the vanadium redox flow battery system is established. The model transformation unit is used to analyze the system state equation obtained from the power bond graph model based on the bond graph theory to evaluate the output performance of the all-vanadium redox flow battery system. The system state equation is used to verify the effectiveness of the power bond graph model. The second model building unit is used to convert the verified power bond graph model into the corresponding block graph model, and to establish a dynamic simulation model of the all-vanadium redox flow battery system by combining the block graph model and the actual operating conditions of the system. The data processing unit is used to obtain the corresponding parameter values ​​in the power bond graph model through experimental data obtained from the dynamic simulation model and bond graph theory, so as to obtain accurate output performance. The control feedback unit is used to change the values ​​of different parameters to obtain the changes in output performance, and to determine the correlation between the values ​​of different parameters and output performance based on the changes, so as to control the adjustment of operating parameters.

5. The control system for the all-vanadium redox flow battery according to claim 4, characterized in that, The hybrid model includes: Electrical control components control the start and stop of pumps, valves, and heat exchangers respectively; Hydraulic components, including pumps, valves, heat exchangers, electrolyte tanks, and piping; The fuel cell stack unit releases voltage and forms an electrolyte circulation circuit with the electrolyte tank via pumps, valves, and heat exchangers.

6. The control system for the all-vanadium redox flow battery according to claim 5, characterized in that, The electronic control unit receives signals from each unit, and the signals from each unit specifically include: The voltage signal transmitted by the pump; The pump transmits pressure and flow signals; Temperature and liquid level signals transmitted from the electrolyte tank; Pressure and flow signals transmitted by valves and testing instruments; The heat exchanger transmits pressure and flow signals; Pressure and flow signals transmitted through pipelines; Pressure and flow signals transmitted by the fuel cell stack; The voltage signal transmitted by the fuel cell stack.

7. The control system for the all-vanadium redox flow battery according to claim 6, characterized in that, After receiving signals from each unit, the electronic control component obtains the corresponding parameter values, then changes the energy loss of each unit in the control system by changing the values ​​of different parameters, and finally obtains the changed parameter values.

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