Electrolytic tank VSG control method and device considering stack thermal constraint

Abstract

The invention provides an electrolytic cell VSG control method and device considering stack thermal constraint, and the method comprises the steps: constructing a thermoelectric coupling model of a proton exchange membrane electrolytic cell grid-connected hydrogen production system, and obtaining the thermoelectric coupling characteristics of a proton exchange membrane electrolytic cell; a corresponding VSG control strategy framework is established by considering thermoelectric coupling characteristics of the proton exchange membrane electrolytic cell, temperature-related baseline damping is set, and the baseline damping is VSG damping; and the VSG damping is adaptively optimized by considering the electrode temperature and the flow change of the proportional valve, so that the electrolytic cell VSG control method considering the stack thermal constraint is obtained. According to the invention, loss caused by local overheating can be reduced, the service life of the proton exchange membrane electrolytic cell is prolonged, and grid-connected stable operation is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrolytic cell control and primary frequency modulation control, and in particular relates to an electrolytic cell VSG control method and device taking into account thermal constraints of a stack. Background Art

[0002] The intermittent and volatile nature of renewable energy generation and the randomness of load demand have brought great challenges to the safe and stable operation of the power grid. When the proton exchange membrane is connected to the grid to produce hydrogen, it can participate in grid auxiliary services by controlling the input power of the electrolyzer, but this process will inevitably change the input power of the electrolyzer, thereby triggering a series of transient processes. The transient process in the PEMWE in a short period of time will cause a large amount of Joule heat to be generated in the electrolyzer, and local overheating will cause thermal runaway, which will not only reduce the service life of the electrolyzer, but also affect the power supply reliability of the power system. The existing electrolyzer control technology lacks flexible and effective thermal management strategies. In view of this, a control strategy that takes into account the thermal constraints of the stack is needed to achieve rapid response to external disturbances while improving the safety and stability of the electrolyzer participating in grid auxiliary services. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides an electrolyzer VSG control method and device taking into account the thermal constraints of the fuel cell stack. By constructing a thermoelectric coupling model of a proton exchange membrane grid-connected hydrogen production system, a VSG control strategy taking into account the thermoelectric coupling characteristics of the electrolyzer is established. This method reduces the losses caused by local overheating when the input power of the electrolyzer changes by establishing a VSG damping adaptive adjustment strategy taking into account the changes in electrode temperature and proportional valve flow, thereby extending the working life of the proton exchange membrane electrolyzer and achieving stable grid-connected operation.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A VSG control method for an electrolyzer considering thermal constraints of a stack, comprising:

[0006] Construct a thermoelectric coupling model of the proton exchange membrane electrolyzer grid-connected hydrogen production system and obtain the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer;

[0007] Considering the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer, a corresponding VSG control strategy framework is established, and a temperature-related baseline damping is set, where the baseline damping is the VSG damping.

[0008] The VSG damping is adaptively optimized considering the changes in electrode temperature and proportional valve flow rate, and then a VSG control method for the electrolyzer considering the thermal constraints of the stack is obtained.

[0009] Furthermore, the thermoelectric coupling model of the proton exchange membrane electrolyzer grid-connected hydrogen production system is constructed to obtain the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer, including:

[0010] The operating voltage of the proton exchange membrane electrolyzer is expressed as:

[0011] ;

[0012] in, is the working voltage of the electrolyzer; is the reversible overpotential; is the activation overpotential; is the Ohm overpotential; is the concentration difference overpotential;

[0013] The equation for the reversible overpotential is:

[0014] ;

[0015] in, is the standard reference potential; is the Faraday constant; is the gas constant; is the reaction temperature; are the pressures of hydrogen and oxygen respectively; is the activity of water between the electrode and the proton exchange membrane;

[0016] The equation for the activation overpotential is:

[0017] ;

[0018] in, are the exchange current densities at the anode and cathode, respectively; are the charge transfer coefficients of the anode and cathode, respectively;

[0019] The equation for Ohm's overpotential is:

[0020] ;

[0021] in, It represents the active area of ​​the electrolytic cell; is the current density; represent the electrode resistance, proton exchange membrane resistance and bipolar plate resistance respectively;

[0022] The equation for concentration overpotential is:

[0023] ;

[0024] in, is the number of electrons transferred during the reaction; is the concentration of oxygen or hydrogen at the interfacial membrane electrode; is the working concentration under reference conditions;

[0025] Build the electrolytic cell temperature model:

[0026] ;

[0027] in, is the heat capacity of the electrolytic cell; is the electrolytic cell inlet temperature; is the electrolytic cell outlet temperature, is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; The heat lost from the electrolyzer to the environment;

[0028] Build the water tank temperature model:

[0029] ;

[0030] ;

[0031] in, is the heat capacity of the water tank; is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; is the water tank outlet temperature; The heat exchanged between the water tank and the environment; is the ambient temperature; is the outlet temperature of the electrolyzer; is the water tank outlet temperature;

[0032] Model the heat exchanger temperature:

[0033] ;

[0034] in, are the heat capacities of the hot and cold sides of the heat exchanger, respectively; are the specific heat capacity and mass of the coolant respectively; is the heat transfer coefficient of the heat exchanger; Let the exchanger cool and measure the outlet and inlet temperatures respectively; is the electrolytic cell inlet temperature; is the water tank outlet temperature; is the logarithmic mean temperature difference;

[0035] Build a proportional valve flow model:

[0036] ;

[0037] in, is the coefficient related to the proportional valve characteristics; is the flow ratio of the proportional valve, which is proportional to the electrode temperature.

[0038] Furthermore, the corresponding VSG control strategy framework is established by considering the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer, and the baseline damping related to temperature is set. The baseline damping is the VSG damping including:

[0039] Establish the VSG simulation synchronous generator rotor motion equation:

[0040] ;

[0041] in:

[0042] ;

[0043] ;

[0044] ;

[0045] In the formula, is the virtual moment of inertia; is the mechanical torque; is the electromagnetic torque; is the virtual angular frequency; is the reference angular frequency; is the virtual damping coefficient; is the torque; is the angular acceleration; is the mechanical angle of the rotor;

[0046] By simulating the droop characteristics of the synchronous generator, the active-frequency control equation and reactive-voltage control equation of the VSG are obtained:

[0047] ;

[0048] In the formula, They are active frequency reference value and virtual mechanical power respectively; They are active power droop coefficient and reactive power droop coefficient respectively; are the reactive power reference value and actual value respectively; are the actual value and reference value of the VSG voltage amplitude respectively;

[0049] Combining the active power-frequency equation with the synchronous generator rotor equation yields:

[0050] ;

[0051] in, Virtual mechanical torque; is the virtual electromagnetic torque; is the virtual electromagnetic power; is the virtual mechanical power;

[0052] According to the output phase of the VSG active-frequency loop and the output voltage amplitude of the reactive voltage loop, the accurate tracking of the VSG output is achieved through the voltage-current double closed loop and SVPWM link;

[0053] The damping coefficient of VSG is:

[0054] ;

[0055] in, is the damping of VSG; is the baseline damping; is adaptive damping; is the adaptive damping component of electrode temperature; Adaptive damping component of proportional valve flow; is the baseline damping coefficient; is the initial temperature of the electrolytic cell.

[0056] Furthermore, the VSG damping is adaptively optimized by considering the electrode temperature and the flow rate change of the proportional valve, and the electrolyzer VSG control method considering the thermal constraint of the stack is obtained, which includes:

[0057] Considering the cathode temperature , anode temperature , membrane electrode temperature The electrode temperature damping component is adaptively adjusted by the proportional valve flow, and the temperature constraint of the electrode under transient conditions is set to: , , ;

[0058] in, is the cathode temperature constraint, is the temperature constraint of the anode, is the temperature constraint of the membrane electrode;

[0059] When the grid frequency rises, the adaptive damping component considering the electrode temperature is expressed as:

[0060] ;

[0061] ;

[0062] in, is the cathode temperature adaptive damping component; is the anode temperature adaptive damping component; is the membrane electrode temperature adaptive damping component; is the frequency difference; They are the real-time temperatures of the cathode, anode and membrane electrode of the electrolyzer respectively;

[0063] When the heat exchanger proportional valve flow is large, the adaptive damping component of the proportional valve flow is considered to be:

[0064] ;

[0065] in, is the flow ratio of the proportional valve;

[0066] When the grid frequency decreases, the adaptive damping component considering the electrode temperature is:

[0067] ;

[0068] ;

[0069] in, They are Moment and Cathode temperature at time They are Moment and Anode temperature at the moment; They are Moment and Membrane electrode temperature at the moment; are the maximum values ​​of the temperature drop per unit time of the cathode, anode and membrane electrode respectively;

[0070] The adaptive damping component considering the proportional valve flow is:

[0071] .

[0072] The present invention also provides an electrolyzer VSG control device taking into account the thermal constraints of the battery stack, comprising the following modules:

[0073] Thermoelectric coupling model building module, which builds the thermoelectric coupling model of the proton exchange membrane electrolyzer grid-connected hydrogen production system and obtains the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer;

[0074] A damping acquisition module is used to establish a corresponding VSG control strategy framework by considering the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer and to set a temperature-related baseline damping, where the baseline damping is the VSG damping.

[0075] The adaptive optimization module adaptively optimizes the VSG damping by considering the changes in electrode temperature and proportional valve flow, and then obtains the electrolyzer VSG control method considering the thermal constraints of the battery stack.

[0076] Furthermore, the thermoelectric coupling model building module realizes:

[0077] The operating voltage of the proton exchange membrane electrolyzer is expressed as:

[0078] ;

[0079] in, is the working voltage of the electrolyzer; is the reversible overpotential; is the activation overpotential; is the Ohm overpotential; is the concentration difference overpotential;

[0080] The equation for the reversible overpotential is:

[0081] ;

[0082] in, is the standard reference potential; is the Faraday constant; is the gas constant; is the reaction temperature; are the pressures of hydrogen and oxygen respectively; is the activity of water between the electrode and the proton exchange membrane;

[0083] The equation for the activation overpotential is:

[0084] ;

[0085] in, are the exchange current densities at the anode and cathode, respectively; are the charge transfer coefficients of the anode and cathode, respectively;

[0086] The equation for Ohm's overpotential is:

[0087] ;

[0088] in, It represents the active area of ​​the electrolytic cell; is the current density; represent the electrode resistance, proton exchange membrane resistance and bipolar plate resistance respectively;

[0089] The equation for concentration overpotential is:

[0090] ;

[0091] in, is the number of electrons transferred during the reaction; is the concentration of oxygen or hydrogen at the interfacial membrane electrode; is the working concentration under reference conditions;

[0092] Build the electrolytic cell temperature model:

[0093] ;

[0094] in, is the heat capacity of the electrolytic cell; is the electrolytic cell inlet temperature; is the electrolytic cell outlet temperature, is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; The heat lost from the electrolyzer to the environment;

[0095] Build the water tank temperature model:

[0096] ;

[0097] ;

[0098] in, is the heat capacity of the water tank; is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; is the water tank outlet temperature; The heat exchanged between the water tank and the environment; is the ambient temperature; is the outlet temperature of the electrolyzer; is the water tank outlet temperature;

[0099] Model the heat exchanger temperature:

[0100] ;

[0101] in, are the heat capacities of the hot and cold sides of the heat exchanger, respectively; are the specific heat capacity and mass of the coolant respectively; is the heat transfer coefficient of the heat exchanger; Let the exchanger cool and measure the outlet and inlet temperatures respectively; is the electrolytic cell inlet temperature; is the water tank outlet temperature; is the logarithmic mean temperature difference;

[0102] Build a proportional valve flow model:

[0103] ;

[0104] in, is the coefficient related to the proportional valve characteristics; is the flow ratio of the proportional valve, which is proportional to the electrode temperature.

[0105] Furthermore, the damping acquisition module implements:

[0106] Establish the VSG simulation synchronous generator rotor motion equation:

[0107] ;

[0108] in:

[0109] ;

[0110] ;

[0111] ;

[0112] In the formula, is the virtual moment of inertia; is the mechanical torque; is the electromagnetic torque; is the virtual angular frequency; is the reference angular frequency; is the virtual damping coefficient; is the torque; is the angular acceleration; is the mechanical angle of the rotor;

[0113] By simulating the droop characteristics of the synchronous generator, the active-frequency control equation and reactive-voltage control equation of the VSG are obtained:

[0114] ;

[0115] In the formula, They are active frequency reference value and virtual mechanical power respectively; They are active power droop coefficient and reactive power droop coefficient respectively; are the reactive power reference value and actual value respectively; are the actual value and reference value of the VSG voltage amplitude respectively;

[0116] Combining the active power-frequency equation with the synchronous generator rotor equation yields:

[0117] ;

[0118] in, Virtual mechanical torque; is the virtual electromagnetic torque; is the virtual electromagnetic power; is the virtual mechanical power;

[0119] According to the output phase of the VSG active-frequency loop and the output voltage amplitude of the reactive voltage loop, the accurate tracking of the VSG output is achieved through the voltage-current double closed loop and SVPWM link;

[0120] The damping coefficient of VSG is:

[0121] ;

[0122] in, is the damping of VSG; is the baseline damping; is adaptive damping; is the adaptive damping component of electrode temperature; Adaptive damping component of proportional valve flow; is the baseline damping coefficient; is the initial temperature of the electrolytic cell.

[0123] Furthermore, the adaptive optimization module realizes:

[0124] Considering the cathode temperature , anode temperature , membrane electrode temperature The electrode temperature damping component is adaptively adjusted by the proportional valve flow, and the temperature constraint of the electrode under transient conditions is set to: , , ;

[0125] in, is the cathode temperature constraint, is the temperature constraint of the anode, is the temperature constraint of the membrane electrode;

[0126] When the grid frequency rises, the adaptive damping component considering the electrode temperature is expressed as:

[0127] ;

[0128] ;

[0129] in, is the cathode temperature adaptive damping component; is the anode temperature adaptive damping component; is the membrane electrode temperature adaptive damping component; is the frequency difference; They are the real-time temperatures of the cathode, anode and membrane electrode of the electrolyzer respectively;

[0130] When the heat exchanger proportional valve flow is large, the adaptive damping component of the proportional valve flow is considered to be:

[0131] ;

[0132] in, is the flow ratio of the proportional valve;

[0133] When the grid frequency decreases, the adaptive damping component considering the electrode temperature is:

[0134] ;

[0135] ;

[0136] in, They are Moment and Cathode temperature at time They are Moment and Anode temperature at the moment; They are Moment and Membrane electrode temperature at the moment; are the maximum values ​​of the temperature drop per unit time of the cathode, anode and membrane electrode respectively;

[0137] The adaptive damping component considering the proportional valve flow is:

[0138] .

[0139] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the above-mentioned electrolyzer VSG control method considering thermal constraints of the battery stack are implemented.

[0140] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-mentioned electrolytic cell VSG control method taking into account the thermal constraints of the battery stack.

[0141] Beneficial effects:

[0142] When a proton exchange membrane electrolyzer encounters a large disturbance, its internal power will fluctuate greatly. At this time, the temperature in the cell cannot be regarded as an isothermal change. Compared with the traditional VSG power frequency control technology with a fixed damping parameter, the present invention is based on the characteristics of the non-uniform distribution of the internal temperature of the proton exchange membrane electrolyzer under transient conditions, and establishes a VSG damping adaptive adjustment strategy that takes into account the changes in electrode temperature and proportional valve flow. This can reduce the losses caused by local overheating and extend the working life of the proton exchange membrane electrolyzer. BRIEF DESCRIPTION OF THE DRAWINGS

[0143] Figure 1 It is a schematic diagram of a VSG control method for an electrolyzer taking into account thermal constraints of the battery stack in an embodiment of the present invention.

[0144] Figure 2 It is a flow chart of a VSG control method for an electrolyzer taking into account thermal constraints of a stack in an embodiment of the present invention. DETAILED DESCRIPTION

[0145] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other. In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0146] like Figure 1 As shown, the present invention implements control for a proton exchange membrane grid-connected hydrogen production system, which includes a wind turbine, a converter, a power grid, a proton exchange membrane electrolyzer, a gas-liquid separator, a heat exchanger, a deionizer, a feed water pump, a circulation pump and a VSG control module.

[0147] like Figure 1 , Figure 2 As shown, in a first aspect, an embodiment of the present invention provides an electrolyzer VSG control method considering thermal constraints of a stack, comprising the following steps:

[0148] S1: Construct a thermoelectric coupling model of the PEM electrolyzer grid-connected hydrogen production system and obtain the thermoelectric coupling characteristics of the PEM electrolyzer;

[0149] S2: Considering the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer, a corresponding VSG control strategy framework is established, and a temperature-related baseline damping is set, where the baseline damping is the VSG damping;

[0150] S3: The VSG damping in S2 is adaptively optimized considering the electrode temperature and proportional valve flow rate changes, and then the electrolyzer VSG control method considering the thermal constraints of the battery stack is obtained.

[0151] Specifically, the S1 includes:

[0152] Wind turbines convert wind energy into mechanical energy and transmit it to generators for power generation. It can be calculated as follows:

[0153] ;

[0154] in, Wind energy captured for wind turbines; is the air density, is the area swept by the wind wheel; is the wind speed; is the wind energy utilization coefficient;

[0155] The operating voltage of the proton exchange membrane electrolyzer can be expressed as:

[0156] ;

[0157] in, is the working voltage of the electrolyzer; is the reversible overpotential; is the activation overpotential; is the Ohm overpotential; is the concentration difference overpotential.

[0158] Furthermore, the reversible overpotential The equation is:

[0159] ;

[0160] in, is the standard reference potential; is the Faraday constant; is the gas constant; is the reaction temperature; are the pressure of hydrogen and the pressure of oxygen respectively; is the activity of water between the electrode and the proton exchange membrane;

[0161] Activation overpotential The equation is:

[0162] ;

[0163] in, are the exchange current density of the anode and the exchange current density of the cathode respectively; are the charge transfer coefficient of the anode and the charge transfer coefficient of the cathode respectively;

[0164] Ohmic overpotential The equation is:

[0165] ;

[0166] in, Indicates the active area of ​​the electrolytic cell; is the current density; They represent electrode resistance, proton exchange membrane resistance, and bipolar plate resistance respectively;

[0167] Concentration overpotential The equation is:

[0168] ;

[0169] in, is the number of electrons transferred during the reaction; is the concentration of oxygen or hydrogen at the interfacial membrane electrode; is the working concentration under reference conditions.

[0170] Furthermore, the S1 also includes establishing a temperature model of the hydrogen production system, including:

[0171] Build the electrolytic cell temperature model:

[0172] ;

[0173] in, is the heat capacity of the electrolytic cell; is the electrolytic cell inlet temperature; is the electrolytic cell outlet temperature, is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; is the heat lost from the electrolytic cell to the environment; t is the time.

[0174] Build the water tank temperature model:

[0175] ;

[0176] ;

[0177] in, is the heat capacity of the water tank; is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; is the water tank outlet temperature; The heat exchanged between the water tank and the environment; is the ambient temperature; is the outlet temperature of the electrolyzer; is the water tank outlet temperature.

[0178] Model the heat exchanger temperature:

[0179] ;

[0180] in, are the heat capacities of the hot and cold sides of the heat exchanger, respectively; are the specific heat capacity of coolant and the mass of coolant respectively; is the heat transfer coefficient of the heat exchanger; are the cold test outlet temperature and inlet temperature of the heat exchanger, respectively; is the electrolytic cell inlet temperature; is the water tank outlet temperature; is the logarithmic mean temperature difference;

[0181] Build a proportional valve flow model:

[0182] ;

[0183] in, is the coefficient related to the proportional valve characteristics; is the flow ratio of the proportional valve, which is proportional to the temperature of the electrolytic cell;

[0184] Specifically, the S2 includes:

[0185] Establish VSG control equation, VSG simulates synchronous generator rotor motion equation:

[0186] ;

[0187] in:

[0188] ;

[0189] Where T is the torque.

[0190] ;

[0191] ;

[0192] in, is the virtual moment of inertia; is the mechanical torque; is the electromagnetic torque; is the virtual angular frequency; is the reference angular frequency; is the virtual damping coefficient; is the torque; is the angular acceleration; is the mechanical angle of the rotor;

[0193] By simulating the droop characteristics of the synchronous generator, the active-frequency control equation and reactive-voltage control equation of the VSG are obtained:

[0194] ;

[0195] In the formula, They are active frequency reference value and virtual mechanical power respectively; They are active power droop coefficient and reactive power droop coefficient respectively; They are reactive power reference value and reactive power actual value respectively; are the actual value of the VSG voltage amplitude and the reference value of the VSG voltage amplitude respectively;

[0196] Combining the active power-frequency equation with the synchronous generator rotor equation yields:

[0197] ;

[0198] in, Virtual mechanical torque; is the virtual electromagnetic torque; is the virtual electromagnetic power; is the virtual mechanical power;

[0199] When facing a large external disturbance of the system, the electrolyzer hydrogen production station adjusts the input power to provide inertia support for the power grid. The change of instantaneous power causes the temperature inside the electrolyzer to change unevenly. Here, the damping coefficient of the VSG is designed considering the thermal constraint of the electrolyzer. The baseline damping is related to the initial temperature of the electrolyzer.

[0200] The damping coefficient of VSG is:

[0201] ;

[0202] in, is the damping of VSG; is the baseline damping; is adaptive damping; is the adaptive damping component of electrode temperature; Adaptive damping component of proportional valve flow; is the baseline damping coefficient; is the initial temperature of the electrolytic cell;

[0203] Specifically, S3 includes:

[0204] The hydrogen production system is equipped with high-precision sensors that can be used to obtain the required parameters in the system, including: grid frequency, electrolyzer temperature, cathode temperature, anode temperature, membrane electrode temperature, current density and proportional valve flow rate;

[0205] ;

[0206] in, is the frequency of the power grid; is the reference frequency of the power grid; is the frequency difference;

[0207] In order to prevent the frequency from fluctuating within a range that does not affect the safety and stability of the system and causing the electrolyzer to operate, a disturbance dead zone of 0.033 Hz is set.

[0208] Considering the cathode temperature , anode temperature , membrane electrode temperature The electrode temperature damping component is adaptively adjusted by the proportional valve flow, and the temperature constraint of the electrode under transient conditions is set to: , , ;

[0209] in, is the cathode temperature constraint, is the temperature constraint of the anode, is the temperature constraint of the membrane electrode;

[0210] When the grid frequency rises, the adaptive damping component considering the electrode temperature can be expressed as:

[0211] ;

[0212] ;

[0213] in, is the cathode temperature adaptive damping component; is the anode temperature adaptive damping component; is the membrane electrode temperature adaptive damping component; is the frequency difference; They are the real-time temperatures of the cathode, anode and membrane electrode of the electrolyzer respectively;

[0214] When the flow rate of the heat exchanger proportional valve is large, the heat of the electrolytic cell dissipates faster, and the damping coefficient is appropriately increased. When the flow rate of the heat exchanger proportional valve is small, the heat of the electrolytic cell dissipates slowly, and the damping coefficient is appropriately reduced.

[0215] The adaptive damping component considering the proportional valve flow is:

[0216] ;

[0217] in, is the flow ratio of the proportional valve;

[0218] When the grid frequency drops;

[0219] The adaptive damping component considering the electrode temperature is:

[0220] ;

[0221] ;

[0222] in, They are The cathode temperature at time Cathode temperature at time They are The anode temperature at the time Anode temperature at the moment; They are The membrane electrode temperature at the time Membrane electrode temperature at the moment; They are the maximum temperature drop per unit time of the cathode, the maximum temperature drop per unit time of the anode, and the maximum temperature drop per unit time of the membrane electrode.

[0223] Consider the flow adaptive damping component of the proportional valve as:

[0224] .

[0225] In a second aspect, an embodiment of the present invention provides an electrolyzer VSG control device taking into account thermal constraints of a stack, comprising the following modules:

[0226] Thermoelectric coupling model building module, which builds the thermoelectric coupling model of the proton exchange membrane electrolyzer grid-connected hydrogen production system and obtains the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer;

[0227] A damping acquisition module is used to establish a corresponding VSG control strategy framework by considering the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer and to set a temperature-related baseline damping, where the baseline damping is the VSG damping.

[0228] The adaptive optimization module adaptively optimizes the VSG damping by considering the changes in electrode temperature and proportional valve flow, and then obtains the electrolyzer VSG control method considering the thermal constraints of the battery stack.

[0229] In a third aspect, an embodiment of the present invention provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the above-mentioned method for controlling VSG of an electrolyzer taking into account thermal constraints of the battery stack are implemented.

[0230] In a fourth aspect, an embodiment of the present invention provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-mentioned electrolyzer VSG control method considering the thermal constraints of the battery stack.

[0231] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The schemes in the embodiments of the present application may be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0232] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0233] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0234] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0235] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0236] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A VSG control method for an electrolyzer considering thermal constraints of a stack, characterized in that: include: Construct a thermoelectric coupling model of the proton exchange membrane electrolyzer grid-connected hydrogen production system and obtain the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer; Considering the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer, a corresponding VSG control strategy framework is established, and a temperature-related baseline damping is set, where the baseline damping is the VSG damping. The VSG damping is adaptively optimized considering the changes in electrode temperature and proportional valve flow rate, and then a VSG control method for the electrolyzer considering the thermal constraints of the stack is obtained.

2. The electrolyzer VSG control method considering stack thermal constraints according to claim 1, characterized in that: The thermoelectric coupling model of the proton exchange membrane electrolyzer grid-connected hydrogen production system is constructed to obtain the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer, including: The operating voltage of the proton exchange membrane electrolyzer is expressed as: ； in, is the working voltage of the electrolyzer; is the reversible overpotential; is the activation overpotential; is the Ohm overpotential; is the concentration difference overpotential; The equation for the reversible overpotential is: ； in, is the standard reference potential; is the Faraday constant; is the gas constant; is the reaction temperature; are the pressures of hydrogen and oxygen respectively; is the activity of water between the electrode and the proton exchange membrane; The equation for the activation overpotential is: ； in, are the exchange current densities at the anode and cathode, respectively; are the charge transfer coefficients of the anode and cathode, respectively; The equation for Ohm's overpotential is: ； in, It represents the active area of ​​the electrolytic cell; is the current density; represent the electrode resistance, proton exchange membrane resistance and bipolar plate resistance respectively; The equation for concentration overpotential is: ； in, is the number of electrons transferred during the reaction; is the concentration of oxygen or hydrogen at the interfacial membrane electrode; is the working concentration under reference conditions; Build the electrolytic cell temperature model: ； in, is the heat capacity of the electrolytic cell; is the electrolytic cell inlet temperature; is the electrolytic cell outlet temperature, is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; The heat lost from the electrolyzer to the environment; Build the water tank temperature model: ； ； in, is the heat capacity of the water tank; is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; is the water tank outlet temperature; The heat exchanged between the water tank and the environment; is the ambient temperature; is the outlet temperature of the electrolyzer; is the water tank outlet temperature; Model the heat exchanger temperature: ； in, are the heat capacities of the hot and cold sides of the heat exchanger, respectively; are the specific heat capacity and mass of the coolant respectively; is the heat transfer coefficient of the heat exchanger; Let the exchanger cool and measure the outlet and inlet temperatures respectively; is the electrolytic cell inlet temperature; is the water tank outlet temperature; is the logarithmic mean temperature difference; Build a proportional valve flow model: ； in, is the coefficient related to the proportional valve characteristics; is the flow ratio of the proportional valve, which is proportional to the electrode temperature.

3. The electrolyzer VSG control method considering stack thermal constraints according to claim 1, characterized in that: The corresponding VSG control strategy framework is established by considering the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer, and the baseline damping related to temperature is set. The baseline damping is the VSG damping including: Establish the VSG simulation synchronous generator rotor motion equation: ； in: ； ； ； In the formula, is the virtual moment of inertia; is the mechanical torque; is the electromagnetic torque; is the virtual angular frequency; is the reference angular frequency; is the virtual damping coefficient; is the torque; is the angular acceleration; is the mechanical angle of the rotor; By simulating the droop characteristics of the synchronous generator, the active-frequency control equation and reactive-voltage control equation of the VSG are obtained: ； In the formula, They are active frequency reference value and virtual mechanical power respectively; They are active power droop coefficient and reactive power droop coefficient respectively; are the reactive power reference value and actual value respectively; are the actual value and reference value of the VSG voltage amplitude respectively; Combining the active power-frequency equation with the synchronous generator rotor equation yields: ； in, Virtual mechanical torque; is the virtual electromagnetic torque; is the virtual electromagnetic power; is the virtual mechanical power; According to the output phase of the VSG active-frequency loop and the output voltage amplitude of the reactive voltage loop, the accurate tracking of the VSG output is achieved through the voltage-current double closed loop and SVPWM link; The damping coefficient of VSG is: ； in, is the damping of VSG; is the baseline damping; is adaptive damping; is the adaptive damping component of electrode temperature; Adaptive damping component of proportional valve flow; is the baseline damping coefficient; is the initial temperature of the electrolytic cell.

4. The electrolyzer VSG control method considering stack thermal constraints according to claim 1, characterized in that: The VSG damping is adaptively optimized by considering the electrode temperature and the flow rate change of the proportional valve, and then the electrolyzer VSG control method considering the thermal constraint of the stack is obtained, which includes: Considering the cathode temperature , anode temperature , membrane electrode temperature The electrode temperature damping component is adaptively adjusted by the proportional valve flow, and the temperature constraint of the electrode under transient conditions is set to: , , ; in, is the cathode temperature constraint, is the temperature constraint of the anode, is the temperature constraint of the membrane electrode; When the grid frequency rises, the adaptive damping component considering the electrode temperature is expressed as: ； ； in, is the cathode temperature adaptive damping component; is the anode temperature adaptive damping component; is the membrane electrode temperature adaptive damping component; is the frequency difference; They are the real-time temperatures of the cathode, anode and membrane electrode of the electrolyzer respectively; When the heat exchanger proportional valve flow is large, the adaptive damping component of the proportional valve flow is considered to be: ； in, is the flow ratio of the proportional valve; When the grid frequency decreases, the adaptive damping component considering the electrode temperature is: ； ； in, They are Moment and Cathode temperature at time They are Moment and Anode temperature at the moment; They are Moment and Membrane electrode temperature at the moment; are the maximum values ​​of the temperature drop per unit time of the cathode, anode and membrane electrode respectively; The adaptive damping component considering the proportional valve flow is: 。 5. A VSG control device for an electrolyzer considering thermal constraints of a stack, characterized in that: Includes the following modules: Thermoelectric coupling model building module, which builds the thermoelectric coupling model of the proton exchange membrane electrolyzer grid-connected hydrogen production system and obtains the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer; A damping acquisition module is used to establish a corresponding VSG control strategy framework by considering the thermoelectric coupling characteristics of the proton exchange membrane electrolyzer and to set a temperature-related baseline damping, where the baseline damping is the VSG damping. The adaptive optimization module adaptively optimizes the VSG damping by considering the changes in electrode temperature and proportional valve flow, and then obtains the electrolyzer VSG control method considering the thermal constraints of the battery stack.

6. The electrolyzer VSG control device considering the thermal constraints of the stack according to claim 5, characterized in that: The thermoelectric coupling model building block implements: The operating voltage of the proton exchange membrane electrolyzer is expressed as: ； in, is the working voltage of the electrolyzer; is the reversible overpotential; is the activation overpotential; is the Ohm overpotential; is the concentration difference overpotential; The equation for the reversible overpotential is: ； in, is the standard reference potential; is the Faraday constant; is the gas constant; is the reaction temperature; are the pressures of hydrogen and oxygen respectively; is the activity of water between the electrode and the proton exchange membrane; The equation for the activation overpotential is: ； in, are the exchange current densities at the anode and cathode, respectively; are the charge transfer coefficients of the anode and cathode, respectively; The equation for Ohm's overpotential is: ； in, It represents the active area of ​​the electrolytic cell; is the current density; represent the electrode resistance, proton exchange membrane resistance and bipolar plate resistance respectively; The equation for concentration overpotential is: ； in, is the number of electrons transferred during the reaction; is the concentration of oxygen or hydrogen at the interfacial membrane electrode; is the working concentration under reference conditions; Build the electrolytic cell temperature model: ； in, is the heat capacity of the electrolytic cell; is the electrolytic cell inlet temperature; is the electrolytic cell outlet temperature, is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; The heat lost from the electrolyzer to the environment; Build the water tank temperature model: ； ； in, is the heat capacity of the water tank; is the electrolyte mass flow rate; is the specific heat capacity of the electrolyte; is the water tank outlet temperature; The heat exchanged between the water tank and the environment; is the ambient temperature; is the outlet temperature of the electrolyzer; is the water tank outlet temperature; Model the heat exchanger temperature: ； in, are the heat capacities of the hot and cold sides of the heat exchanger, respectively; are the specific heat capacity and mass of the coolant respectively; is the heat transfer coefficient of the heat exchanger; Let the exchanger cool and measure the outlet and inlet temperatures respectively; is the electrolytic cell inlet temperature; is the water tank outlet temperature; is the logarithmic mean temperature difference; Build a proportional valve flow model: ； in, is the coefficient related to the proportional valve characteristics; is the flow ratio of the proportional valve, which is proportional to the electrode temperature.

7. The electrolyzer VSG control device considering the thermal constraints of the stack according to claim 5, characterized in that: The damping acquisition module realizes: Establish the VSG simulation synchronous generator rotor motion equation: ； in: ； ； ； In the formula, is the virtual moment of inertia; is the mechanical torque; is the electromagnetic torque; is the virtual angular frequency; is the reference angular frequency; is the virtual damping coefficient; is the torque; is the angular acceleration; is the mechanical angle of the rotor; By simulating the droop characteristics of the synchronous generator, the active-frequency control equation and reactive-voltage control equation of the VSG are obtained: ； In the formula, They are active frequency reference value and virtual mechanical power respectively; They are active power droop coefficient and reactive power droop coefficient respectively; are the reactive power reference value and actual value respectively; are the actual value and reference value of the VSG voltage amplitude respectively; Combining the active power-frequency equation with the synchronous generator rotor equation yields: ； in, Virtual mechanical torque; is the virtual electromagnetic torque; is the virtual electromagnetic power; is the virtual mechanical power; According to the output phase of the VSG active-frequency loop and the output voltage amplitude of the reactive voltage loop, the accurate tracking of the VSG output is achieved through the voltage-current double closed loop and SVPWM link; The damping coefficient of VSG is: ； in, is the damping of VSG; is the baseline damping; is adaptive damping; is the adaptive damping component of electrode temperature; Adaptive damping component of proportional valve flow; is the baseline damping coefficient; is the initial temperature of the electrolytic cell.

8. The electrolyzer VSG control device considering thermal constraints of the stack according to claim 5, characterized in that: The adaptive optimization module realizes: Considering the cathode temperature , anode temperature , membrane electrode temperature The electrode temperature damping component is adaptively adjusted by the proportional valve flow, and the temperature constraint of the electrode under transient conditions is set to: , , ; in, is the cathode temperature constraint, is the temperature constraint of the anode, is the temperature constraint of the membrane electrode; When the grid frequency rises, the adaptive damping component considering the electrode temperature is expressed as: ； ； in, is the cathode temperature adaptive damping component; is the anode temperature adaptive damping component; is the membrane electrode temperature adaptive damping component; is the frequency difference; They are the real-time temperatures of the cathode, anode and membrane electrode of the electrolyzer respectively; When the heat exchanger proportional valve flow is large, the adaptive damping component of the proportional valve flow is considered to be: ； in, is the flow ratio of the proportional valve; When the grid frequency decreases, the adaptive damping component considering the electrode temperature is: ； ； in, They are Moment and Cathode temperature at time They are Moment and Anode temperature at the moment; They are Moment and Membrane electrode temperature at the moment; are the maximum values ​​of the temperature drop per unit time of the cathode, anode and membrane electrode respectively; The adaptive damping component considering the proportional valve flow is: 。 9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of a method for controlling VSG of an electrolyzer taking into account thermal constraints of a stack as described in any one of claims 1 to 4 are implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of a method for controlling an electrolyzer VSG taking into account thermal constraints of a stack as described in any one of claims 1 to 4 are implemented.

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