Hydrogen production efficiency coordination control method and system of wind storage coordination hydrogen production system

Abstract

The invention discloses a hydrogen production efficiency coordination control method and system of a wind storage coordination hydrogen production system, and belongs to the technical field of wind power hydrogen production. According to historical operation data of an electrolytic cell, a smoothing factor corresponding to each operation scene is determined; on the basis of the running scene and the smoothing factor of the electrolytic bath at the current moment, the smoothing power at the current moment is obtained through weighted average of the smoothing power at the previous moment and the wind power at the current moment; determining an energy storage coordination control strategy corresponding to each operation scene; according to the running scene and the smooth power of the electrolytic cell at the current moment, when the smooth power meets the preset total running power and running time threshold value corresponding to the running scene when the electrolytic cell runs to the running scene, the hydrogen production efficiency is controlled in a coordinated mode by executing an energy storage coordination control strategy corresponding to the running scene; otherwise, switching to another operation scene. According to the method, smooth power of different scenes is coordinated through charging and discharging power of energy storage, so that optimal operation of the wind storage coordinated hydrogen production system is realized.

Description

Technical Field

[0001] This invention relates to the field of wind power hydrogen production technology, and more specifically to a method and system for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system. Background Technology

[0002] Hydrogen production via water electrolysis using renewable energy can effectively promote the integration of wind and solar power and optimize the energy structure. Fully and rationally utilizing wind and solar power can improve their utilization rate, reduce curtailment, and mitigate fluctuations in wind and solar power output, which is highly beneficial to the development of low-carbon initiatives and the "dual-carbon" goal. Hydrogen production via water electrolysis is classified into grid-connected and off-grid types based on whether it is coupled with the power grid.

[0003] Among them, grid-connected hydrogen production can work with electric energy storage to smooth out the fluctuations in wind and solar power output, use surplus electricity to produce hydrogen, and when the grid needs it, hydrogen energy can also be converted into electricity to stabilize the grid power transmission. Traditional research on grid-connected hydrogen production mainly focuses on the control, capacity configuration and optimized scheduling of hydrogen energy storage and electric energy storage. There are also scenario operation control for the working characteristics and design of electrolyzers, which are called rule control strategies.

[0004] Off-grid hydrogen production relies primarily on renewable energy sources such as wind and solar power, as it lacks grid support. The volatility of wind and solar power significantly impacts the stability, efficiency, and lifespan of the electrolyzer in off-grid hydrogen production processes. Most research on off-grid hydrogen production considers control strategies and capacity configurations for electro-hydrogen production systems that address factors such as wind and solar power volatility. The core objective of both is to achieve optimal power allocation and improve the stability, efficiency, and economics of the hydrogen production system. Traditional off-grid hydrogen production research often incorporates predictive methods. Predicting wind power output allows wind-storage coordinated hydrogen production systems to respond in advance, buffering the impact of sudden power fluctuations on the electrolyzers in these systems.

[0005] The wind-storage coordinated hydrogen production system consists of a wind turbine, lithium iron phosphate battery energy storage, and an auto-electrolyte (AWE). The wind turbine is the only power supply device for the system. Lithium iron phosphate battery energy storage has advantages such as high safety, long cycle life, and low cost, and it also has a fast response speed, making it very suitable for coordinating input power. The AWE is the key equipment for water electrolysis to produce hydrogen. For off-grid wind power hydrogen production, ensuring the stability of the AWE hydrogen production process is a prerequisite for ensuring hydrogen production efficiency.

[0006] While rule-based control strategies can stabilize the operation of grid-connected wind-storage coordinated hydrogen production systems, they struggle to adapt to the fluctuating characteristics of wind power in off-grid scenarios. Introducing rule-based control strategies into wind-storage coordinated hydrogen production systems can mitigate power fluctuations, but it complicates the control rules, leading to confusion in the system's judgments. This results in frequent switching and start-ups / shutdowns of the AWE (Automatic Wind Power) operating environment, reducing the stability of the hydrogen production process and impacting efficiency. Summary of the Invention

[0007] To address the problems existing in the above-mentioned fields, this invention proposes a method and system for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system. This method can adopt the optimal energy storage coordinated control strategy based on the current operating state of the electrolyzer, achieving precise control and dynamic adjustment of the electrolyzer's operating power, which can significantly improve hydrogen production efficiency and reduce energy loss.

[0008] To address the aforementioned technical problems, this invention discloses a method for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system, comprising the following steps: A mathematical model of the electrolyzer in the wind-storage coordinated hydrogen production system was established to obtain the hydrogen production efficiency characteristic curve and operating characteristics of the electrolyzer. The operating scenarios of the electrolyzer were determined, including start-up power, high-efficiency power, rated power and overload power. Based on the historical operating data of the electrolyzer, the smoothing factor corresponding to each operating scenario is determined; based on the operating scenario and smoothing factor of the electrolyzer at the current moment, the smoothing power at the current moment is obtained by weighted averaging of the smoothed power at the previous moment and the wind power at the current moment. Determine the energy storage coordination control strategy corresponding to each operating scenario; based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the preset total operating power and operating time threshold corresponding to the operating scenario, execute the energy storage coordination control strategy corresponding to the operating scenario to coordinate and control the hydrogen production efficiency; otherwise, switch to another operating scenario.

[0009] Preferably, the energy storage coordination control strategy for each operating scenario is determined as follows: in the start-up power scenario, energy storage maintains smooth power; in the high-efficiency power scenario, energy storage compensates for the gap between smooth power and wind power; in the rated power scenario, energy storage coordinates wind power; and in the overload power scenario, energy storage does not operate.

[0010] Preferably, based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the preset total operating power and operating time threshold corresponding to the operating scenario, the hydrogen production efficiency is coordinated and controlled by executing the energy storage coordination control strategy corresponding to that operating scenario; otherwise, the process switches to another operating scenario, specifically including: Based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power is sufficient for at least one electrolyzer to operate at the start-up power and reach the preset operating time, the system switches from the start-up power scenario to the high-efficiency power scenario and maintains the smoothing power through energy storage. When the smoothing power meets the requirement that at least one electrolyzer operates at high power and reaches the preset operating time, the system switches from the high power scenario to the rated power scenario, and uses energy storage to make up for the gap between the smoothing power and the wind power. When the smoothing power exceeds the rated power of all electrolyzers and the preset operating time is reached, the system switches from the rated power scenario to the overload power scenario, and coordinates the wind power through energy storage. In the overload power scenario, the operating power of each electrolytic cell is the average of the smoothed power. When the preset operating time is reached or the operating power does not exceed the total rated power, the system switches from the overload power scenario to the rated power scenario, and the energy storage does not operate.

[0011] Preferably, the step of switching from the start-up power scenario to the high-efficiency power scenario based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power satisfies at least one electrolyzer operating at its start-up power for a preset operating time, and maintaining the smoothing power through energy storage, specifically includes: Through the current t Time-smooth power P ref ( t and the starting power of the electrolytic cell P st The ratio is used to determine the total number of operating electrolytic cells under the start-up power scenario. q for: In the formula: Represents rounding down to the nearest integer. q =1, 2, ..., n , n Take a positive integer to represent the total number of electrolytic cells in operation; when P ref ( t )≥ P st + δ At that time, the operating power of the electrolytic cell from P st Begin with no more than r _ramp The rate increases smoothly until it reaches the current power or high-efficiency power. P b The corresponding number i Operating power of the Taiwan electrolytic cell P e,i ( t )for: In the formula: δ The start-up hysteresis of the wind-storage coordinated hydrogen production system is set to 0.1. P st ; r _ ramp Due to the slope ratio limitation, i =1, 2, ...,q ; The running time for determining the operating status of the electrolytic cell is as follows T under ; when P ref ( t )< P st At that time, the electrolytic cell was operating in the following state: In the formula, P standby This refers to standby power. Based on the operating time of the electrolytic cell, the operating states of the electrolytic cell are determined, including start-up, standby, and shutdown; when the operating state is start-up, the operating power of the electrolytic cell is... P st When the operating status is shutdown, the operating power of the electrolytic cell is 0. Through the charging and discharging power of energy storage P ess ( t Coordinated smoothing power P ref ( t ),when P w ( t )> P ref ( t When ), energy storage charges; when P w < P ref ( t When this happens, the stored energy is discharged to maintain... P ref ( t ); When the energy storage SOC reaches 90%, charging stops and the efficiency is increased. P ref ( t ); When the stored energy SOC = 10%, discharge is stopped and the setting is lowered. P ref ( t ) to match P w ( t ).

[0012] Preferably, when the smoothing power meets the requirement that at least one electrolyzer operates at high efficiency power and reaches a preset operating time, the process switches from the high efficiency power scenario to the rated power scenario, using energy storage to compensate for the gap between the smoothing power and wind power. Specifically, this includes: Determine the total number of operating electrolyzers under high-power scenarios. k for: In the formula, Represents rounding down to the nearest integer. k =1, 2, ..., n ; In high-power scenarios, the operating power of the electrolytic cell P e,i(t) for: When smoothing power P ref ( t )> n · P b At that time, running time T _under When the time is ≥15 minutes, switch the operation of the electrolytic cell to the rated power scenario. k The operating power of +1 electrolytic cell is sufficient for the startup power scenario. P ref ( t )≥ P st + δ Changes in operating power over time; when P ref ( t )< k · P b At that time, running time T _under When the time interval is ≥15 minutes, the smoothing power at the current moment is evenly distributed to k TECH Robotics: when P ref ( t )<( k -1)· P b At that time, running time T _ under When ≥15min, the k One of the electrolytic cells is running at startup power and updating simultaneously. k = k -1, remaining k The operating power of one electrolytic cell is: Compensation through energy storage P ref (t )and P w ( t The instantaneous difference: When the energy storage SOC = 90%, charging stops and is adjusted upwards. P ref ( t Consume excess P w ( t ).

[0013] Preferably, when the smoothing power exceeds the rated power of all electrolyzers and a preset operating time is reached, the process switches from the rated power scenario to the overload power scenario, coordinating wind power through energy storage, specifically including: When all the electrolyzers in the wind-storage coordinated hydrogen production system gradually operate to their rated power P When the rated power scenario is in progress, the upper limit of the smoothed power at the current moment is determined as follows: The operating power of the electrolytic cell gradually increases from its current value to its rated power. P : when P ref ( t ) ≥ n · P At that time, running time T _under For ≥30 minutes, energy storage will preferentially absorb excess wind power. P w ( t ): When the energy storage SOC=90%, charging stops and the wind-storage coordinated hydrogen production system switches to the overload power scenario. when P w ( t )< n · P At that time, energy storage discharge can compensate for wind power loss. P w ( t )gap: If the energy storage continues to discharge time T _ess_dis ≥ 30 min, from T _ess_dis Sustained momentsT _trigger Start, smooth power P ref ( t From the current value n · P Begins to decrease linearly: Among them, the rate of descent r ramp_down The settings must ensure that the power decrease every 30 minutes does not exceed the difference between the rated power and the high-efficiency power of one electrolytic cell. when P ref ( t ) ≤ n · P b When switching to the high-efficiency power scenario.

[0014] Preferably, in the overload power scenario, the operating power of each electrolytic cell is the average of the smoothed power. When a preset operating time is reached or the operating power does not exceed the total rated power, the system switches from the overload power scenario to the rated power scenario, and the energy storage does not operate. Specifically, this includes: Determine the operating power of the electrolyzer under overload power scenarios. P e,i ( t )for: Obtain the running time of the electrolytic cell under overload power scenario. T _ overload ,when T _ overload ≥ 15 min or P e,i ( t ) ≤ n · P When switching from the overload power scenario back to the rated power scenario; During overload power scenarios, the energy storage does not operate: P ess ( t = 0.

[0015] Preferably, the step of establishing a mathematical model of the electrolyzer in the wind-storage coordinated hydrogen production system, obtaining the efficiency characteristic curve and operating characteristics of the electrolyzer, and determining the operating scenarios of the electrolyzer, includes start-up power, high-efficiency power, rated power, and overload power, specifically including: Based on a semi-empirical model, the voltage-current relationship of the electrolyzer is established, i.e., the mathematical model is: In the formula: U cell This refers to the voltage in the small chamber of the electrolytic cell; U rev This is the voltage of the electrolytic cell when no current flows. I el This represents the current in the electrolytic cell; r 1. r 2. S , t 1. t 2. t 3 represents electrochemically relevant parameters; A el The electrode area; T el The temperature of the electrolyte; An electrolytic cell consists of several electrolytic cell chambers connected in series and parallel. The voltage of the electrolytic cell... U el Represented as: In the formula: N el This refers to the number of cells in the electrolytic cell; Determine the hydrogen production efficiency of the electrolyzer. for: In the formula, For voltage efficiency, The Faraday efficiency of the electrolytic cell; In the formula: U th This is the thermal neutral voltage of the electrolytic cell; Based on the mathematical model of the electrolyzer, the hydrogen production efficiency characteristic curve of the electrolyzer is obtained; According to the hydrogen production efficiency characteristic curve of the electrolyzer, the hydrogen production efficiency of the electrolyzer first rises rapidly to the highest efficiency point with the increase of power, then slowly decreases and gradually stabilizes. The working characteristics of the electrolyzer include cold start and hot start during operation. Based on the efficiency characteristic curve and operating characteristics of the electrolyzer, the operation process of the electrolyzer is divided into four scenarios: starting power, high-efficiency power, rated power, and overload power.

[0016] Preferably, the step of determining the smoothing factor corresponding to each operating scenario based on the historical operating data of the electrolyzer; and obtaining the smoothed power at the current moment by weighted averaging the smoothed power at the previous moment and the wind power at the current moment based on the operating scenario and smoothing factor of the electrolyzer at the current moment, specifically includes: Based on the historical operating data of the electrolyzer, the smoothing factor for different scenarios is determined by empirical methods, optimization methods, or adaptive methods. Get current t Wind power of the electrolytic cell at any given time P w ( t Based on the discrete-time difference equation form of first-order low-pass filtering, the smoothed power command equation for the electrolytic cell is constructed as follows: In the formula: P ref ( t ) is the current t Smooth power at any given moment; P w ( t ) is the current t Wind power output at any given moment; α Let be the smoothing factor, 0 ≤ α ≤1; α The closer to 1, the better. P ref ( t The slower the change, the more stable the wind-storage coordinated hydrogen production system, but the greater the delay in tracking wind power trends and the larger the required energy storage capacity. The smoothed power at the current moment is determined by the smoothed power command equation of the electrolyzer.

[0017] Preferably, it also includes a hydrogen production efficiency coordination control system for a wind-storage coordinated hydrogen production system, comprising: The multi-scenario segmentation module for electrolyzer operation is used to establish a mathematical model of the electrolyzer in the wind-storage coordinated hydrogen production system, obtain the hydrogen production efficiency characteristic curve and operating characteristics of the electrolyzer, and determine the operating scenarios of the electrolyzer, which include start-up power, high-efficiency power, rated power and overload power. The smoothing power determination module is used to determine the smoothing factor corresponding to each operating scenario based on the historical operating data of the electrolyzer; based on the operating scenario and smoothing factor of the electrolyzer at the current moment, the smoothing power at the current moment is obtained by weighted averaging the smoothing power at the previous moment and the wind power at the current moment. The hydrogen production efficiency coordination control module is used to determine the energy storage coordination control strategy corresponding to each operating scenario. Based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the preset total operating power and operating time threshold corresponding to the operating scenario, the energy storage coordination control strategy corresponding to the operating scenario is executed to coordinate and control the hydrogen production efficiency; otherwise, the module switches to another operating scenario.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The proposed method for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system divides the electrolyzer operation into four scenarios—start-up, high-efficiency, rated, and overload—based on efficiency characteristic curves and operating characteristics. This allows for a deeper understanding of the electrolyzer's performance under different operating conditions and fully considers the specific needs of the electrolyzer at different operating stages, thereby more effectively improving hydrogen production efficiency and providing an accurate theoretical basis for developing targeted control strategies for different scenarios. Based on a smoothing factor determined from historical operating data, the current smoothed power is calculated by a weighted average of the smoothed power from the previous moment and the current wind power, effectively reducing the impact of wind power fluctuations on electrolyzer operation and improving system stability and reliability. According to the current operating scenario and smoothed power of the electrolyzer, the energy storage coordinated control strategy for different operating scenarios is dynamically switched to coordinate and control hydrogen production efficiency. By optimizing the operating power of the electrolyzer under different operating scenarios, unnecessary energy loss and equipment wear are reduced, lowering operating costs. Simultaneously, the optimal energy storage coordinated control strategy can be adopted for the current operating state of the electrolyzer, achieving precise control and dynamic adjustment of the electrolyzer's operating power, effectively improving the overall economic efficiency of the wind-storage coordinated hydrogen production system. This method effectively adapts to the fluctuations and uncertainties in wind power, ensuring the stable operation of the hydrogen production system under varying wind speeds. This is of great significance for improving the utilization rate of renewable energy and reducing dependence on traditional energy sources. Attached Figure Description

[0019] Figure 1 This is a flowchart of the hydrogen production efficiency coordination control method for the wind-storage coordinated hydrogen production system proposed in this invention. Figure 2 This is a schematic diagram of the voltage-current relationship curve of an electrolytic cell provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the series and parallel connection of the electrolytic cell chambers provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the efficiency-power relationship curve of an electrolytic cell provided in an embodiment of the present invention; Figure 5 is a detailed control flowchart of strategy A provided in an embodiment of the present invention, wherein: Figure 5(a) is a flowchart of the smoothing power determination provided in an embodiment of the present invention; Figure 5(b) is a flowchart of the start-up power point scenario control provided in an embodiment of the present invention; Figure 5(c) is a flowchart of the optimal / high-efficiency power point scenario control provided by an embodiment of the present invention; Figure 5(d) is a flowchart of the rated power point scenario control provided in an embodiment of the present invention; Figure 5(e) is a flowchart of the overload power point scenario control provided in an embodiment of the present invention; Figure 6 The wind power output data of the xx wind farm over 8760 hours provided in this embodiment of the invention; Figure 7 A comparison curve of wind power and electrolyzer power for Strategy A provided in this embodiment of the invention; Figure 8 This is a comparison curve of wind power and electrolyzer power for Strategy B provided in an embodiment of the present invention; Figure 9 A comparison curve of wind power and electrolyzer power for Strategy C provided in this embodiment of the invention; Figure 10 A comparison chart of electrolyzer power under different strategies over a selected 24-hour period is provided for embodiments of the present invention. Figure 11 This is a comparison chart of the operating times of electrolyzers for different strategies provided in the embodiments of the present invention; Figure 12 This is a comparison chart of the number of start-ups and shutdowns of electrolyzers for each strategy provided in the embodiments of the present invention; Figure 13 Power distribution curves of electrolyzers for various strategies provided in embodiments of the present invention. Detailed Implementation

[0020] The following will refer to the appendices in the embodiments of the present invention. Figures 1-13 The technical solutions in the embodiments of the present invention will be clearly and completely described. It should be understood that the terminology used in the present invention is only for describing particular implementation methods and is not intended to limit the present invention.

[0021] Example like Figure 1 As shown, this invention proposes a method for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system, comprising the following steps: S1: Establish a mathematical model of the electrolyzer in the wind-storage coordinated hydrogen production system, obtain the hydrogen production efficiency characteristic curve and operating characteristics of the electrolyzer, and determine the operating scenario of the electrolyzer, which includes start-up power, high-efficiency power, rated power and overload power. S2: Based on the historical operating data of the electrolyzer, determine the smoothing factor corresponding to each operating scenario; based on the operating scenario and smoothing factor of the electrolyzer at the current moment, obtain the smoothing power at the current moment by weighted average of the smoothing power at the previous moment and the wind power at the current moment. S3: Determine the energy storage coordination control strategy corresponding to each operating scenario; based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the total operating power and operating time requirements corresponding to the current operating scenario of the electrolyzer, execute the energy storage coordination control strategy corresponding to that operating scenario to coordinate and control the hydrogen production efficiency; otherwise, switch to another operating scenario.

[0022] Specifically, in step S1, the present invention establishes the voltage-current relationship of the electrolytic cell based on a semi-empirical model, i.e., the mathematical model is as follows: (1) In the formula: U cell This refers to the voltage in the small chamber of the electrolytic cell; U rev This is the voltage of the electrolytic cell when no current flows. I el This represents the current in the electrolytic cell; r 1. r 2. S , t 1. t 2. t 3 represents electrochemically relevant parameters; A el The electrode area; T el The temperature of the electrolyte, such as Figure 2 The figure shows the voltage-current relationship curve of the electrolytic cell.

[0023] like Figure 3 The diagram shows an electrolytic cell apparatus, which consists of several electrolytic cell chambers connected in series and parallel. The voltage of the electrolytic cell... U el Represented as: (2) In the formula: N el This refers to the number of cells in the electrolytic cell.

[0024] The hydrogen production efficiency of an electrolyzer consists of its voltage efficiency and its Faraday efficiency. The voltage efficiency is obtained by the ratio of the thermal neutral voltage to the actual voltage. In the formula: η e For voltage efficiency, U th This is the thermal neutral voltage of the electrolytic cell.

[0025] Under constant temperature and pressure conditions, the Faraday efficiency of the electrolytic cell is: In the formula, For Faraday efficiency.

[0026] The hydrogen production efficiency of the electrolyzer was obtained. for: From formulas (1)-(5), the hydrogen production efficiency characteristic curves of the electrolyzer (AWE) (the curves showing the hydrogen production efficiency following the power change) can be obtained, such as Figure 4 As shown.

[0027] from Figure 4 As can be seen, the hydrogen production efficiency of the electrolyzer first rises rapidly to the highest efficiency point with the increase of power, then slowly decreases and gradually stabilizes. Therefore, the electrolyzer power corresponding to the highest hydrogen production efficiency is a relatively small light load power.

[0028] AWE Working Characteristics Analysis Because AWE has special operating power requirements, firstly, the minimum operating power of AWE cannot be too low, generally 15% to 20% of the rated power. This is because excessively low operating power will increase the ratio of hydrogen to oxygen mixture, which is very detrimental to production safety. Secondly, the maximum operating power of AWE can be overloaded, generally 110% to 130% of the rated power, but the overload time should not be too long, otherwise it will damage the equipment, reduce performance, and shorten the service life of AWE.

[0029] The AWE startup process is generally divided into cold start and hot start. Cold start refers to the process of the AWE transitioning from a shutdown state to a normal operating state. During this process, the AWE first consumes power to raise the hydrogen production temperature, thus consuming [power].

[0030] The initial startup time is relatively long, typically 15-60 minutes. However, when an AWE (Automatic External Defibrillator) pauses operation after a period of time, it maintains a certain temperature. If the AWE restarts at this point, the startup time is significantly shortened, requiring only a few minutes – a hot start. Furthermore, the process of an AWE transitioning from normal operation to shutdown takes only seconds. In short, the AWE's operating power exhibits a characteristic of requiring a longer time to increase from low to high power, and vice versa.

[0031] By establishing a mathematical model of the electrolyzer and obtaining its hydrogen production efficiency characteristic curve and operating characteristics, we can gain a deeper understanding of the electrolyzer's performance under different operating conditions. This provides an accurate theoretical basis for subsequently developing targeted control strategies based on different scenarios, making the control methods more closely aligned with the actual operating conditions of the electrolyzer and avoiding efficiency losses caused by blind control. Therefore, the operation and control of the AWE (Average Power Output) must fully consider its efficiency and operating characteristics.

[0032] Based on the efficiency characteristic curve and operating characteristics of the electrolyzer, the electrolyzer operation process is divided into four scenarios: start-up, high efficiency, rated operation, and overload. This fully considers the special needs of the electrolyzer at different operating stages, thereby more effectively improving hydrogen production efficiency. The operating power of the electrolyzer is determined to be [0.2]. P 1.2 P ],in, P The rated power; determine the starting power of the electrolytic cell. P st =0.2 P The maximum overload power is 1.2. P The maximum duration of each overload and stable operation is 15 minutes; the operating power corresponding to the highest hydrogen production efficiency is determined to be 0.35. P That is, the high efficiency power of the electrolytic cell is P b =0.35 P The overload power of the electrolytic cell was determined to be 0.15. P .

[0033] While the rule-based control strategies of grid-connected wind-storage coordinated hydrogen production systems can ensure relatively stable operation, they are ill-suited to the fluctuating characteristics of wind power in off-grid scenarios. Introducing energy storage systems can mitigate power fluctuations, but it complicates control rules, potentially leading to system decision confusion, frequent switching of AWE (Active Energy Response) operating scenarios, and frequent start-stop cycles, thereby reducing the stability of the hydrogen production process.

[0034] In step S2, based on the historical operating data of the electrolyzer, a smoothing factor corresponding to different scenarios is determined using empirical, optimization, or adaptive methods. The value of this smoothing factor fully considers the operating experience and actual performance of the electrolyzer under different scenarios. The historical operating data contains rich information, and by analyzing and mining this data, the most suitable smoothing factor for each operating scenario can be found, so that the smoothing power can play its best role in each operating scenario, further improving hydrogen production efficiency.

[0035] Based on the smoothing factor corresponding to each operating scenario, a smoothing power command equation for the electrolyzer is constructed. The smoothing power at the current moment is obtained by weighted averaging of the smoothing power at the previous moment and the wind power at the current moment.

[0036] The constructed smooth power command equation for the electrolyzer is as follows: (6) In the formula: P ref ( t ) is the current t Smooth power at any given moment; P w (t () is the current data obtained through measurement t Real-time wind power output at any given moment; α Let be the smoothing factor, 0 ≤ α ≤1.

[0037] α The closer to 1, the better. P ref ( t The slower the change, the more stable the system, but the greater the delay in tracking wind power trends, and the greater the energy storage capacity required.

[0038] The constructed smooth power command equation can smooth the wind power, making the power command received by the electrolyzer more stable, reducing the frequent start-up and shutdown of the electrolyzer and efficiency fluctuations caused by power fluctuations, thereby improving the stability and efficiency of the hydrogen production process.

[0039] The smoothed power command equation for the electrolyzer is similar to an "inertial" system. The new command value is a weighted average of the old command value and the new wind power value, so that any sudden changes in wind power are applied to the electrolyzer smoothly and delayed. The coordinating role of energy storage also plays a key role. In this strategy, it is only necessary to make up for the instantaneous power gap, without needing to judge the trend of wind power.

[0040] Based on the smoothing factor corresponding to each operating scenario, the smoothed power of each operating scenario at the current moment is obtained by weighted averaging the smoothed power of each operating scenario at the previous moment and the wind power at the current moment.

[0041] This weighted average calculation method takes into account both the operating status at the previous moment and the wind power change at the current moment, which can more smoothly transition power commands, avoid the impact of sudden power changes on the electrolyzer, and ensure the stability of hydrogen production efficiency.

[0042] Real-time acquisition of wind power from the electrolyzer in a wind-storage coordinated hydrogen production system allows for timely monitoring of dynamic changes in energy input. Wind power is volatile and uncertain; real-time monitoring provides accurate data support for subsequent power smoothing control, enabling flexible adjustments to control methods based on actual wind power conditions and ensuring the stable operation of the hydrogen production system.

[0043] To this end, this embodiment of the invention provides a power segmentation smoothing control strategy based on multiple scenarios, which transforms the complex multi-rule control strategy into a single target control strategy with the total AWE power demand as the core, and achieves power smoothing through an energy storage coordination strategy. In step S3, based on the discrete-time difference equation form of the first-order low-pass filter, the smoothing power command equation of the electrolytic cell is constructed to determine the smoothing power of each operating scenario at the current moment, as shown in Figure (a) of Figure 5.

[0044] In step S3 of this invention, an energy storage coordination control strategy is determined for each operating scenario. In the startup power scenario, energy storage is used to maintain smooth power. In the high-efficiency power scenario, energy storage is used to make up for the gap between smooth power and wind power. In the rated power scenario, energy storage is used to coordinate wind power. In the overload power scenario, energy storage does not operate.

[0045] Based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the preset total operating power and operating time threshold corresponding to the operating scenario, the hydrogen production efficiency is coordinated and controlled by executing the energy storage coordination control strategy corresponding to the operating scenario; otherwise, the system switches to another operating scenario.

[0046] The following are the specific energy storage coordination control strategy design and the method flow design for coordinating and controlling hydrogen production efficiency in four operating scenarios during the operation of the electrolyzer.

[0047] 1) Through the current t Time-smooth power P ref ( t and the starting power of the electrolytic cell P st The ratio is used to determine the total number of operating electrolytic cells under the start-up power scenario. q for: (7) In the formula: Represents rounding down to the nearest integer. q =1, 2, ..., n , n Take a positive integer to represent the total number of electrolytic cells in operation.

[0048] As shown in Figure 5(b), in the startup power scenario, a larger smoothing factor is set to maintain a certain stability during the electrolyzer startup process. α To reduce the volatility of the electrolyzer startup process, i.e., a smoothing factor. α Choose a larger value to ensure that the power changes are slow and smooth, avoiding fluctuations.

[0049] when P ref ( t )≥ P st + δ At that time, the operating power of the electrolytic cell from P st Begin with no more than r_ ramp The rate of increase is smooth until the current power or high-efficiency power (optimal power) is reached. P b The corresponding number iOperating power of the Taiwan electrolytic cell P e,i ( t )for: (8) In the formula: δ The start-up hysteresis of the wind-storage coordinated hydrogen production system is set to 0.1. P st ; r_ ramp Due to the slope ratio limitation, i =1, 2, ..., q ; The running time for real-time acquisition of the electrolytic cell's operating status is T _ under ; Then when P ref ( t )< P st At that time, based on the running time T _ under The operating status of the electrolytic cell is determined by starting up, standby, and stopping. Operating power of the electrolytic cell corresponding to each operating state P e,i ( t )for: (9) In the formula: P _ standby The operating power of the electrolytic cell in standby mode; When the operating status is start-up, the operating power of the electrolytic cell is P st ; When the operating status is shutdown, the operating power of the electrolytic cell is 0.

[0050] Obtain the charging and discharging power of energy storage P ess ( t )for: (10) in, P w ( t This indicates the real-time wind power output of the electrolyzer; Through the charging and discharging power of energy storage P ess ( t Coordinated smoothing power P ref ( t ),when P w( t )> P ref ( t When ), energy storage charges; when P w ( t )< P ref ( t When this happens, the stored energy is discharged to maintain... P ref ( t ); When the energy storage SOC reaches 90%, charging stops and the efficiency is increased. P ref ( t ); When the stored energy SOC = 10%, discharge is stopped and the setting is lowered. P ref ( t ) to match P w ( t ); 2) Obtain the total number of operating electrolyzers under high-efficiency power scenarios. k for: (11) In the formula, Represents rounding down to the nearest integer. k =1, 2, ..., n .

[0051] The main purpose of high-efficiency power scenarios is to improve hydrogen production efficiency by prioritizing the operation of as many electrolyzers as possible at their high-efficiency power points. P b .

[0052] As shown in Figure 5(c), in the high-efficiency / optimal power scenario, a larger smoothing factor is set to delay wind power changes, thereby increasing the high-efficiency operating time of the electrolyzer. α Take the larger value, so that P ref ( t It can slowly track wind power trends.

[0053] In high-power scenarios, the operating power of the electrolytic cell P e,i ( t )for: (12) When smoothing power P ref ( t )> n · Pb At that time, running time T _ under When the time is ≥15 minutes, switch the operation of the electrolytic cell to the rated power scenario. In equation (12), the first... k The operating power of +1 electrolytic cell is still based on equation (8) under the starting power scenario, i.e., when P ref ( t )≥ P st + δ Changes in operating power over time;

[0054] when P ref ( t )< k · P b At that time, running time T _ under When the time interval is ≥15 minutes, the smoothing power at the current moment is evenly distributed to k TECH Robotics: (13) when P ref ( t )<( k -1)· P b At that time, running time T_ under When ≥15min, the k One of the electrolytic cells is running at startup power and updating simultaneously. k = k -1, remaining k The operating power of one electrolytic cell is: (14) Energy storage to compensate P ref ( t )and P w ( t The instantaneous difference: (15) When the energy storage SOC = 90%, charging stops and is adjusted upwards. P ref ( t Consume excess P w ( t ); 3) Under rated power conditions, as shown in Figure 5(d), all nThe electrolytic cells in Taiwan are gradually operating at their rated power. P In order to ensure that the electrolyzer can fully absorb wind power, the smoothing factor α Take the larger value, so that P ref ( t It can slowly track wind power trends, with an upper limit of: (16) The operating power of the electrolytic cell gradually increases from its current value to its rated power. P : (17) when P ref ( t ) ≥ n · P At that time, running time T _ under For ≥30 minutes, energy storage will preferentially absorb excess wind power. P w ( t ): (18) When the energy storage SOC=90%, charging stops and the wind-storage coordinated hydrogen production system immediately switches to the overload power scenario. when P w ( t )< n · P At that time, energy storage discharge can compensate for wind power loss. P w ( t )gap: (19) If the energy storage continues to discharge time T _ ess_dis ≥ 30 min, from T _ess_dis Sustained moments T _ trigger Start, smooth power P ref ( t From the current value n · P Begins to decrease linearly: (20) Among them, the rate of descent r ramp_down The settings must ensure that the power decrease every 30 minutes does not exceed the difference between the rated power and the high-efficiency power of one electrolytic cell. (twenty one) when P ref ( t ) ≤ n · P b When switching from the rated power scenario back to the high-efficiency power scenario; 4) In the overload power scenario, as shown in Figure 5(e), the electrolyzer is allowed to operate under short-term overload. To maximize the short-term operating power of the electrolyzer and further absorb wind power, a smoothing factor is used. α Take the smaller value, so that P ref ( t It can quickly respond to high wind power output. In overload power scenarios, P ref ( t The upper limit is dynamically set to 1.2. n · P Operating power of each electrolytic cell P e,i ( t The mean of the smoothed power at the current moment is:

[0055] (twenty two) And start the overload timer to obtain the running time of the electrolytic cell under overload power scenario. T _ overload ,when T _ overload ≥ 15 min or P e,i ( t ) ≤ n · P When switching from the overload power scenario back to the rated power scenario; During overload power scenarios, the energy storage does not operate: P ess ( t ) = 0; when P w ( t )>1.2 n · P At that time, excess wind power was abandoned.

[0056] The energy storage coordination control strategy provided by this invention for each operating scenario can fully utilize the energy storage system, storing excess energy when wind power is excessive and releasing stored energy when wind power is insufficient, thereby maintaining the stable operation of the electrolyzer and efficient hydrogen production. Through the coordinated operation of the energy storage control strategy and the electrolyzer's operating power, optimized energy allocation is achieved, further improving the hydrogen production efficiency and energy utilization rate of the entire wind-storage coordinated hydrogen production system.

[0057] The above is a detailed execution flow of the segmented smooth control strategy (energy storage coordinated control strategy) proposed in this invention for the hydrogen production efficiency coordinated control method, as shown in Figures (a)-(e) of Figure 5. This process adopts the state machine design concept. After the wind-storage coordinated hydrogen production system is initialized, it starts running from the start-up power scenario and operates according to the smooth power command calculated in real time. P ref ( t The system compares the total operating power threshold and operating time threshold corresponding to each operating scenario, dynamically switches operating scenarios, and coordinates the actions of the energy storage system.

[0058] The process begins with real-time wind power... P w ( t Perform a first-order low-pass filter to generate smoothed power. P ref ( t ). System continuous monitoring P ref ( t The size and duration of the energy storage system are used to determine whether to switch to a higher or lower order scenario, and to coordinate the actions of the energy storage system to achieve optimal system operation.

[0059] The specific switching conditions for each scene are as follows: The condition for transitioning from scenario 1) to scenario 2): when P ref ( t )> P st For a certain period of time, and with the current smoothing power sufficient to support at least one electrolyzer operating at its high-efficiency power point. P b Nearby (i.e.) k When the value is 1), the wind-storage coordinated hydrogen production system switches to a high-efficiency operation scenario.

[0060] The condition for transitioning from scenario 2) to scenario 3): When P ref ( t )> n · P bWhen the continuous operating time reaches the power threshold under high-efficiency power scenarios, i.e., wind power... P w ( t When the capacity is sufficient to support all electrolyzers operating at rated power and there is still a surplus, the wind-storage coordinated hydrogen production system enters the rated power scenario.

[0061] Conditions for transitioning from scenario 3) to scenario 4): Under the rated scenario, if P ref ( t )>n· P If the operating time threshold is continuously reached and the state of charge (SOC) of the energy storage is ≥90%, the wind-storage coordinated hydrogen production system will enter an overload power scenario.

[0062] The condition for switching back to a lower-order scenario from a higher-order scenario: when wind power decreases, causing... P ref ( t If the power level falls below the threshold required to maintain the current scenario for a certain period of time, the system will revert to a scenario with an even lower power level. The energy storage coordination strategy is applied across all scenarios, and its charging and discharging power... P ess ( t )= P w ( t )- P ref ( t When SOC reaches the limit boundary, adjust... P ref ( t It participates in system power balance to prevent overcharging and over-discharging.

[0063] The control process proposed in this invention transforms complex multi-rule decisions into clear state machine switching and combines them with explicit mathematical formulas, ensuring the stable and efficient operation of the off-grid wind-storage hydrogen production system under different fluctuation scenarios.

[0064] This invention also proposes a hydrogen production efficiency coordination control system for a wind-storage coordinated hydrogen production system, comprising: The multi-scenario segmentation module for electrolyzer operation is used to establish a mathematical model of the electrolyzer in the wind-storage coordinated hydrogen production system, obtain the hydrogen production efficiency characteristic curve and operating characteristics of the electrolyzer, and determine the operating scenarios of the electrolyzer, which include start-up power, high-efficiency power, rated power and overload power. The smoothing power determination module is used to determine the smoothing factor corresponding to each operating scenario based on the historical operating data of the electrolyzer; based on the operating scenario and smoothing factor of the electrolyzer at the current moment, the smoothing power at the current moment is obtained by weighted averaging the smoothing power at the previous moment and the wind power at the current moment. The hydrogen production efficiency coordination control module is used to determine the energy storage coordination control strategy corresponding to each operating scenario. Based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the preset total operating power and operating time threshold corresponding to the operating scenario, the energy storage coordination control strategy corresponding to the operating scenario is executed to coordinate and control the hydrogen production efficiency; otherwise, the module switches to another operating scenario.

[0065] This method can adopt the optimal energy storage coordination control strategy according to the current operating status of the electrolyzer, realizing precise control and dynamic adjustment of the electrolyzer's operating power, and providing a new solution for wind-storage coordinated hydrogen production systems.

[0066] Case Analysis This paper uses 8760 hours of wind power output data from the xx wind farm and extracts data within 30MW as input to analyze and verify the coordinated control method of the off-grid wind-storage coordinated hydrogen production system proposed in this invention. The sampling time is 15 minutes, with a total of 35040 sampling points. Figure 6 As shown, wind power output is abundant but highly volatile. This invention uses four identical electrolyzers for hydrogen production, each with a rated power of 5MW. The AWE parameters are shown in Table 1.

[0067] Table 1 Electrolyte and Energy Storage Parameters To comprehensively evaluate the performance of the control method proposed in this invention, it is compared and analyzed with two traditional control strategies through simulation. Strategy A represents the control method proposed in this invention, and Strategy B represents a rule-based control strategy. Strategy C introduces an energy storage coordination element based on Strategy B to highlight the advantages of this invention's method in integrating energy storage coordination. Simulations are conducted under the same typical wind conditions to compare and analyze the effectiveness of each strategy in smoothing wind power fluctuations and improving the stability and efficiency of the electrolyzer operation from both macroscopic power coordination characteristics and microscopic operating indicators. First, each strategy is applied to the aforementioned wind conditions, and the comparison of wind power output and electrolyzer power after the application of each strategy is macroscopically presented to compare the effectiveness of each strategy.

[0068] like Figure 7 As shown, this is a comparison curve of wind power output and electrolyzer power provided by Strategy A in an embodiment of the present invention. Figure 8 As shown, this is a comparison curve of wind power output and electrolyzer power provided by Strategy B in an embodiment of the present invention. Figure 9 As shown, this is a comparison curve of wind power output and electrolyzer power provided by Strategy C in an embodiment of the present invention. Figure 10 The figure shown is a comparison chart of electrolytic cell power under different strategies within a selected 24-hour period, provided by an embodiment of the present invention.

[0069] from Figure 7 It is evident that in the scenario of strategy A, the period when the electrolytic cell power is at a low power level is significantly reduced, and the time below 5MW is shorter, which indirectly indicates that the range of change in electrolytic cell power has been greatly reduced.

[0070] And from Figure 10 As can be seen, the electrolyzer power variation driven by strategy A of this invention is very smooth, and it can cope with severe wind power fluctuations. This is because of the smoothing factor. α The settings ensure that the electrolyzer power smoothly follows the wind power, reducing drastic power fluctuations. Of course, prioritizing energy storage charging during the initial simulation phase is necessary to establish a sufficient energy buffer, providing support for smoothing subsequent power fluctuations and ensuring adequate coordination of the electrolyzer power during later operation. The key device for smoothing electrolyzer power is energy storage. The energy storage operates according to the target command... P ref ( t )and P w ( t The difference between charging and discharging makes P ref ( t The changes in the energy storage system are not as drastic, allowing the coordinating effect of energy storage to be fully utilized. Therefore, the strategy of this invention has a strong effect on off-grid hydrogen production processes, fully demonstrating the effectiveness of the method proposed in this invention.

[0071] Figure 8 In Strategy B, the electrolyzer power is always above 0, which effectively reduces the start-up time because a hot start is much shorter than a cold start. However, the electrolyzer remains at low power for a longer period, which is detrimental to the safety of the equipment. On the other hand, without the assistance of energy storage coordination, the electrolyzer power fluctuates only with wind speed, often resulting in significant power drops and drastic power changes. Figure 10 This is clearly evident in the process. Therefore, equipping off-grid hydrogen production with energy storage is necessary to mitigate wind power fluctuations and reduce damage to electrolyzer equipment. Consequently, Strategy B is less effective for off-grid hydrogen production.

[0072] Figure 9 While Strategy C considers energy storage coordination, providing some support for the electrolyzer's operating power, low-power scenarios are still common under this strategy. This is because wind power is the primary energy source for hydrogen production in electrolyzers, and the electrolyzer's power output remains significantly influenced by wind power. Energy storage plays only a weak coordinating role, although it can also affect the electrolyzer's status. Figure 10As can be seen, under strategy C, the change in electrolyzer power only lags slightly behind that under strategy B, slightly delaying the change in electrolyzer power, but it cannot significantly affect the operating status of the electrolyzer, failing to leverage the advantages of energy storage. Therefore, although the control rule strategy with energy storage coordination can help reduce the impact of wind power fluctuations on the electrolyzer, it does not improve the problem of the electrolyzer's long low-power period.

[0073] On the other hand, the length of time the electrolyzer operates can also reflect the effectiveness of the control strategy in controlling and managing the electrolyzer's operation. Figure 11 The chart shows a comparison of the operating times of electrolyzers under different strategies. In Strategy A, the operating times of each electrolyzer are the longest, generally exceeding 7000 hours. In Strategy B and Strategy C, the operating times are similar, both exceeding 6000 hours but not exceeding 7000 hours. In Strategy B, the operating time of the electrolyzers varies with wind power output, inevitably limited by wind power fluctuations. In the latter, the charging and discharging support of energy storage only lags the power changes of the electrolyzers and does not significantly increase their operating time. It should be noted that all three strategies assume a rotating management system for electrolyzer numbering, and assume that the performance of each electrolyzer is balanced across the three strategies, without considering the balance of electrolyzer operation.

[0074] Meanwhile, the longer operating time of the electrolyzer in each strategy also implies stronger stability in the electrolyzer operation process. For example... Figure 12 The chart shows a comparison of the number of start-ups and shutdowns of the electrolyzers under different strategies. It is clear that the number of start-ups and shutdowns for strategy A is significantly lower than that for strategies B and C. This is due to the setting of the smoothing factor. In scenario 1), to reduce frequent power fluctuations and start-ups / shutdowns during normal operation, the smoothing factor is set to 0.99 in scenarios 1), 2), and 3), striving to maintain stable power operation and improve the electrolyzer's performance in high-power scenarios. Meanwhile, in scenario 4), the electrolyzer power is set to 0.8. Because environmental factors are not a major concern for power overload in scenario 4), and a maximum overload time is specifically set, the power changes in scenario 4 will be slightly more frequent.

[0075] Since the power of the electrolyzer can only follow the fluctuations of wind power, strategies B and C are ineffective because the power of the electrolyzer can only follow the fluctuations of wind power. Although strategy B is designed based on the working characteristics of the electrolyzer, it is difficult to play a role in the severe wind environment. The simple addition of energy storage in strategy C can only delay the short-term fluctuations of the electrolyzer's power, but cannot truly play a coordinating role. It is also difficult to cope with the severe fluctuations of wind power in a timely manner. Therefore, we need to change our thinking and make energy storage a real means of smoothing power rather than simply charging and discharging.

[0076] Simulation results show that under Strategy A of the present invention, the electrolytic cell system experiences a total of 235 starts and 231 shutdowns, significantly lower than the total of 2226 starts and 2222 shutdowns under rule-based control Strategy B, and the total of 2215 starts and 2211 shutdowns under rule-based control Strategy C with energy storage coordination. Frequent start-ups and shutdowns of the AWE (Automatic Welding Environment) exacerbate electrode aging and diaphragm wear, and reduce system lifespan and reliability due to repeated thermal cycling. Therefore, Strategy A of the present invention, by introducing smooth power commands and a standby mechanism, largely avoids unnecessary start-ups and shutdowns, which is highly beneficial for improving the operational stability and lifespan of the electrolytic cell.

[0077] Table 2 Expected power and standard deviation of electrolyzers for each strategy like Figure 13 The figure shows the power distribution curves of the electrolyzers for each strategy. The power distribution of strategies A, B, and C is analyzed and compared from the perspective of the normal power distribution curves of the electrolyzers. Table 2 shows the expected power and standard deviation of the electrolyzers for each strategy.

[0078] According to Table 2 and Figure 13 It is clear that the expected value μ of all three strategies is approximately 15MW. However, while the standard deviations of strategies B and C are nearly identical (both above 9.6), the standard deviation σ of strategy A is smaller than that of strategies B and C. According to the normal distribution theory, when expected values ​​are similar, curves with smaller variances exhibit less volatility. Therefore, strategy A's smoothing of wind power not only provides a more stable operating environment for the electrolyzer but also increases the efficient operating time of the electrolyzer, demonstrating the superiority of strategy A.

[0079] Table 3 Comparison of hydrogen production performance indicators for different strategies in electrolyzers Table 3 shows that, by comparing the average hydrogen production rates of each strategy, Strategy A's average hydrogen production rate and total hydrogen production are slightly lower than those of Strategy B and Strategy C. However, Strategy A's system weighted average efficiency is higher than that of Strategy B and Strategy C, and its total power consumption is lower than that of Strategy B and Strategy C. This indicates that Strategy A produces a similar amount of hydrogen with lower power consumption as Strategy B and Strategy C, and its hydrogen production efficiency is also slightly higher than the latter two. Therefore, Strategy A fully utilizes the setting of the smoothing factor and the effective coordination of energy storage to increase the electrolyzer power to the high-efficiency power range for a longer period, thereby improving the electrolyzer's hydrogen production efficiency and demonstrating the relative superiority of Strategy A in terms of hydrogen production efficiency.

[0080] To address the problem that traditional rule-based control strategies are ill-suited for off-grid wind power hydrogen production processes due to the strong fluctuations in wind power output, this invention first establishes a mathematical model of the electrolyzer and analyzes its efficiency characteristic curve and operating characteristics. Based on this, it proposes a smoothing power command equation and a piecewise power smoothing control strategy for the electrolyzer, constructed using the discrete-time difference equation of a first-order low-pass filter. Through case studies, it compares this strategy with rule-based control strategies and rule-based control strategies considering energy storage coordination, verifying the effectiveness of Strategy A of this invention. Specific conclusions are as follows: For the segmented power smoothing control strategy, the specific strategy divides the electrolyzer operation into four scenarios—start-up, high-efficiency, rated, and overload—based on the electrolyzer efficiency curve and operating characteristics. Each scenario is then combined with a smoothing power command equation. This is achieved by setting a smoothing factor for each scenario. α The weighted average of the smoothed power at the previous moment and the wind power at the current moment is used to obtain the current moment's wind power. P ref ( t And achieve segmented smooth control through energy storage coordination strategy.

[0081] Compared with rule-based control strategies and rule-based control strategies that take into account energy storage coordination, Strategy A of the present invention shows significant advantages in improving the stability of the electrolyzer and reducing the number of start-ups and shutdowns, reducing the number of start-ups and shutdowns by approximately 89%, and producing a similar amount of hydrogen with less than 3% of the power consumption.

[0082] In summary, the method proposed in this invention is applicable to off-grid wind power hydrogen production scenarios and can provide valuable reference for practical production.

[0083] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0084] Furthermore, unless otherwise stated, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. All references to this specification are incorporated by way of citation to disclose and describe methods relating to those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

Claims

1. A method for coordinated control of hydrogen production efficiency of a wind storage coordinated hydrogen production system, characterized by, Includes the following steps: A mathematical model of the electrolyzer in the wind-storage coordinated hydrogen production system was established to obtain the hydrogen production efficiency characteristic curve and operating characteristics of the electrolyzer. The operating scenarios of the electrolyzer were determined, including start-up power, high-efficiency power, rated power and overload power. Based on the historical operating data of the electrolyzer, the smoothing factor corresponding to each operating scenario is determined; based on the operating scenario and smoothing factor of the electrolyzer at the current moment, the smoothing power at the current moment is obtained by weighted averaging of the smoothed power at the previous moment and the wind power at the current moment. Determine the energy storage coordination control strategy corresponding to each operating scenario; based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the preset total operating power and operating time threshold corresponding to the operating scenario, execute the energy storage coordination control strategy corresponding to the operating scenario to coordinate and control the hydrogen production efficiency; otherwise, switch to another operating scenario. 2.The hydrogen production efficiency coordination control method of the wind storage coordination hydrogen production system according to claim 1, characterized in that, The energy storage coordination control strategy for each operating scenario is determined as follows: in the start-up power scenario, energy storage maintains smooth power; in the high-efficiency power scenario, energy storage makes up for the gap between smooth power and wind power; in the rated power scenario, energy storage coordinates wind power; and in the overload power scenario, energy storage does not operate. 3.The hydrogen production efficiency coordination control method of the wind storage coordination hydrogen production system according to claim 2, characterized in that, Based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the preset total operating power and operating time threshold corresponding to the operating scenario, the hydrogen production efficiency is coordinated and controlled by executing the energy storage coordination control strategy corresponding to that operating scenario; otherwise, the system switches to another operating scenario, specifically including: Based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power is sufficient for at least one electrolyzer to operate at the start-up power and reach the preset operating time, the system switches from the start-up power scenario to the high-efficiency power scenario and maintains the smoothing power through energy storage. When the smoothing power meets the requirement that at least one electrolyzer operates at high power and reaches the preset operating time, the system switches from the high power scenario to the rated power scenario, and uses energy storage to make up for the gap between the smoothing power and the wind power. When the smoothing power exceeds the rated power of all electrolyzers and the preset operating time is reached, the system switches from the rated power scenario to the overload power scenario, and coordinates the wind power through energy storage. In the overload power scenario, the operating power of each electrolytic cell is the average of the smoothed power. When the preset operating time is reached or the operating power does not exceed the total rated power, the system switches from the overload power scenario to the rated power scenario, and the energy storage does not operate. 4.The method of claim 3, wherein, The step of switching from the start-up power scenario to the high-efficiency power scenario based on the current operating scenario and smoothing power of the electrolyzers, when the smoothing power satisfies at least one electrolyzer operating at its startup power for a preset operating time, and maintaining the smoothing power through energy storage, specifically includes: By the current t Smoothed power at the moment P ref ( t ) and the start-up power of the electrolytic cell P st The total number of electrolytic cells in the start-up power scenario is determined by the ratio of the current q : In the formula: represents rounding down, q =1, 2, …, n , n Take positive integer, indicating the total number of electrolytic cell operation platform; When P ref ( t )≥ P st + δ , the running power of the electrolytic cell starts to smoothly rise at a rate not exceeding P st , until it reaches the current power or the high-efficiency power r _ramp , the running power of the corresponding first P b electrolytic cell is: i P e,i ( t )​ In the formula: δ is the start-up hysteresis of the wind-storage coordinated hydrogen production system, and is 0.1 P st r ramp is the climbing rate limit, i =1, 2, …, q ;​​ The running time for determining the running state of the electrolytic cell is T under ; When P ref ( t ) < P st the cell is in a state of operation: In the formula, P standby P is the standby power; According to the running time of the electrolytic cell running state, the running state of the electrolytic cell is determined, including starting, standby and shutdown; when the running state is the starting state, the running power of the electrolytic cell is P st ; when the running state is the shutdown state, the running power of the electrolytic cell is 0; Charging and discharging power of energy storage P ess ( t ) coordinating smooth power P ref ( t ), when P w ( t )> P ref ( t ) energy storage charging; when P w < P ref ( t ) energy storage discharges to maintain P ref ( t ); When the energy storage SOC = 90%, stop charging, increase P ref ( t ); When the energy storage SOC = 10%, stop discharging and turn down P ref ( t ) to match P w ( t ). 5.The method of claim 4, wherein, When the smoothing power meets the requirement that at least one electrolyzer operates at high power and reaches a preset operating time, the system switches from the high-power scenario to the rated power scenario, using energy storage to compensate for the gap between the smoothing power and wind power. Specifically, this includes: Determining total number of operating cells in high efficiency power scenario k For: wherein represents a floor function, k = 1, 2,... n ; In high-power scenarios, the operating power of the electrolytic cell P e,i(t) for: When smoothing power P ref ( t )> n · P b At that time, running time T _under When the time is ≥15 minutes, switch the operation of the electrolytic cell to the rated power scenario. k The operating power of +1 electrolytic cell is sufficient for the startup power scenario. P ref ( t )≥ P st + δ Changes in operating power over time; when P ref ( t )< k · P b At that time, running time T _under When the time interval is ≥15 minutes, the smoothing power at the current moment is evenly distributed to k TECH Robotics: when P ref ( t )< ( k -1)· P b At that time, running time T _ under When ≥15min, the k One of the electrolytic cells is running at startup power and updating simultaneously. k = k -1, remaining k The operating power of one electrolytic cell is: Compensation through energy storage P ref ( t )and P w ( t The instantaneous difference: When the energy storage SOC = 90%, charging stops and is adjusted upwards. P ref ( t Consume excess P w ( t ).

6. The method for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system according to claim 5, characterized in that, When the smoothing power exceeds the rated power of all electrolyzers and the preset operating time is reached, the system switches from the rated power scenario to the overload power scenario, coordinating wind power through energy storage. Specifically, this includes: When all the electrolyzers in the wind-storage coordinated hydrogen production system gradually operate to their rated power P When the rated power scenario is in progress, the upper limit of the smoothed power at the current moment is determined as follows: The operating power of the electrolytic cell gradually increases from its current value to its rated power. P : when P ref ( t ) ≥ n · P At that time, running time T _under For ≥30 minutes, energy storage will preferentially absorb excess wind power. P w ( t ): When the energy storage SOC=90%, charging stops and the wind-storage coordinated hydrogen production system switches to the overload power scenario. when P w ( t )< n · P At that time, energy storage discharge can compensate for wind power loss. P w ( t )gap: If the energy storage continues to discharge time T _ess_dis ≥ 30 min, from T _ess_dis Sustained moments T _trigger Start, smooth power P ref ( t From the current value n · P Begins to decrease linearly: Among them, the rate of descent r ramp_down The settings must ensure that the power decrease every 30 minutes does not exceed the difference between the rated power and the high-efficiency power of one electrolytic cell. when P ref ( t ) ≤ n · P b When switching to the high-efficiency power scenario.

7. The method for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system according to claim 6, characterized in that, In the overload power scenario, the operating power of each electrolytic cell is the average of the smoothed power. When the preset operating time is reached or the operating power does not exceed the total rated power, the system switches from the overload power scenario to the rated power scenario, and the energy storage does not operate. Specifically, this includes: Determine the operating power of the electrolyzer under overload power scenarios. P e,i ( t )for: Obtain the running time of the electrolytic cell under overload power scenario. T _ overload ,when T _ overload ≥ 15 min or P e,i ( t )≤ n · P When switching from the overload power scenario back to the rated power scenario; During overload power scenarios, the energy storage does not operate: P ess ( t = 0.

8. The method for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system according to claim 1, characterized in that, The mathematical model of the electrolyzer in the wind-storage coordinated hydrogen production system is established to obtain the efficiency characteristic curve and operating characteristics of the electrolyzer, and to determine the operating scenarios of the electrolyzer. These operating scenarios include start-up power, high-efficiency power, rated power, and overload power, specifically including: Based on a semi-empirical model, the voltage-current relationship of the electrolyzer is established, i.e., the mathematical model is: In the formula: U cell This refers to the voltage in the small chamber of the electrolytic cell; U rev This is the voltage of the electrolytic cell when no current flows. I el This represents the current in the electrolytic cell; r 1. r 2. S , t 1. t 2. t 3 represents electrochemically relevant parameters; A el The electrode area; T el The temperature of the electrolyte; An electrolytic cell consists of several electrolytic cell chambers connected in series and parallel. The voltage of the electrolytic cell... U el Represented as: In the formula: N el This refers to the number of cells in the electrolytic cell; Determine the hydrogen production efficiency of the electrolyzer. for: In the formula, For voltage efficiency, The Faraday efficiency of the electrolytic cell; In the formula: U th This is the thermal neutral voltage of the electrolytic cell; Based on the mathematical model of the electrolyzer, the hydrogen production efficiency characteristic curve of the electrolyzer is obtained; According to the hydrogen production efficiency characteristic curve of the electrolyzer, the hydrogen production efficiency of the electrolyzer first rises rapidly to the highest efficiency point with the increase of power, then slowly decreases and gradually stabilizes. The working characteristics of the electrolyzer include cold start and hot start during operation. Based on the efficiency characteristic curve and operating characteristics of the electrolyzer, the operation process of the electrolyzer is divided into four scenarios: starting power, high-efficiency power, rated power, and overload power.

9. The method for coordinated control of hydrogen production efficiency in a wind-storage coordinated hydrogen production system according to claim 8, characterized in that, The process involves determining a smoothing factor for each operating scenario based on historical operating data of the electrolyzer; and obtaining the smoothed power at the current moment by weighted averaging the smoothed power from the previous moment and the wind power at the current moment, based on the current operating scenario and smoothing factor of the electrolyzer. Specifically, this includes: Based on the historical operating data of the electrolyzer, the smoothing factor for different scenarios is determined by empirical methods, optimization methods, or adaptive methods. Get current t Wind power of the electrolytic cell at any given time P w ( t Based on the discrete-time difference equation form of first-order low-pass filtering, the smoothed power command equation for the electrolytic cell is constructed as follows: In the formula: P ref ( t ) is the current t Smooth power at any given moment; P w ( t ) is the current t Wind power output at any given moment; α Let be the smoothing factor, 0 ≤ α ≤1; α The closer to 1, the better. P ref ( t The slower the change, the more stable the wind-storage coordinated hydrogen production system, but the greater the delay in tracking wind power trends and the larger the required energy storage capacity. The smoothed power at the current moment is determined by the smoothed power command equation of the electrolyzer.

10. A hydrogen production efficiency coordination control system for a wind-storage coordinated hydrogen production system, characterized in that, include: The multi-scenario segmentation module for electrolyzer operation is used to establish a mathematical model of the electrolyzer in the wind-storage coordinated hydrogen production system, obtain the hydrogen production efficiency characteristic curve and operating characteristics of the electrolyzer, and determine the operating scenarios of the electrolyzer, which include start-up power, high-efficiency power, rated power and overload power. The smoothing power determination module is used to determine the smoothing factor corresponding to each operating scenario based on the historical operating data of the electrolyzer; based on the operating scenario and smoothing factor of the electrolyzer at the current moment, the smoothing power at the current moment is obtained by weighted averaging the smoothing power at the previous moment and the wind power at the current moment. The energy storage coordination strategy control module is used to determine the energy storage coordination control strategy corresponding to each operating scenario. Based on the current operating scenario and smoothing power of the electrolyzer, when the smoothing power meets the preset total operating power and operating time threshold corresponding to the operating scenario, the energy storage coordination control strategy corresponding to the operating scenario is executed to coordinate and control the hydrogen production efficiency; otherwise, the system switches to another operating scenario.

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