An electric-hydrogen-thermal hybrid energy storage capacity configuration method for smoothing sea wind fluctuations

Abstract

A kind of electric hydrogen heat hybrid energy storage capacity configuration method for smoothing sea wind fluctuation, comprising the following steps: step 1: construct the dynamic temperature model of alkaline electrolyzer (alkaline electrolyzer, AEL), the model is used to characterize the thermal state evolution process of AEL under variable condition;Step 2: based on the dynamic temperature model, combine the preset thermal safety threshold and minimum continuous operation time, formulate AEL self-temperature maintenance operation strategy;Step 3: according to daily offshore wind fluctuation, and combined with the thermal state availability that AEL self-temperature maintenance strategy can maintain, construct dynamic interaction interval model, determine the collaborative action boundary between electric energy storage and hydrogen energy storage;Step 4: based on the dynamic interaction interval constructed in step 3, construct the energy management strategy of hybrid energy storage system;Step 5: based on the dynamic temperature model of step 1, the AEL self-temperature maintenance strategy of step 2, the dynamic interaction interval model of step 3 and the energy management strategy of step 4, construct the capacity configuration optimization model and capacity configuration evaluation model of electric hydrogen heat hybrid energy storage system.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and in particular to a hybrid electric-hydrogen-thermal energy storage capacity configuration technology for mitigating offshore wind power fluctuations. Specifically, it relates to a method for configuring hybrid electric-hydrogen-thermal energy storage capacity to mitigate offshore wind fluctuations based on a dynamic interaction range. Background Technology

[0002] Global grid connection standards for wind power generally require certain technical measures at the sending end to limit the amplitude of power fluctuations. Among these, hybrid energy storage systems, which utilize the complementary advantages of different energy storage technologies, can smooth power fluctuations in offshore wind farms. Against this backdrop, hybrid electric-hydrogen energy storage systems are the fastest-growing category, and companies such as Crosswind and Total Energy have begun planning to deploy them at the grid connection points of offshore wind farms. However, the capacity configuration of hybrid electric-hydrogen energy storage systems is a key factor determining the smoothing effect, stable operation, and economic viability; improper configuration can easily lead to insufficient smoothing capacity or over-investment.

[0003] Paper 10.19912 / j.0254-0096.tynxb.2024-1074 proposes a capacity configuration method for smoothing wind power fluctuations in hybrid electro-hydrogen energy storage based on interactive intervals. This paper introduces two fixed interactive intervals, allowing the alkaline electrolyzer (AEL) and proton exchange membrane fuel cell (PEMFC) to start in advance. Both operate simultaneously with electrochemical energy storage within their respective intervals, strengthening the complementary mechanism of the electro-hydrogen hybrid energy storage system and reducing its investment cost. However, this research only improves the planning scheme of the electro-hydrogen hybrid energy storage system, neglecting the heat required for the AEL to maintain its temperature under various operating conditions, resulting in planning results that do not conform to reality. In actual engineering, the Levenmouth offshore wind farm has added a thermal storage system to recover the heat generated when configuring hydrogen energy storage. Therefore, it is possible to consider building an electric-hydrogen-thermal hybrid energy storage system to mitigate wind power fluctuations while utilizing the thermal storage system for heat recovery and meeting AEL temperature requirements.

[0004] Reference 10.20204 / j.sp.2025.05006 constructs an electro-hydrogen-thermal hybrid energy storage system to mitigate wind power fluctuations. This paper establishes an AEL (Alternating Energy Storage Unit) self-insulating model, utilizing the heat from the storage tank for insulation when the AEL's own heat generation is insufficient. Simultaneously, the paper utilizes a wind curtailment heating device to further mitigate wind power fluctuations, also providing thermal support for the system. However, this method neglects the AEL's temperature change process, assuming it immediately reaches a predetermined temperature when switching between different operating conditions. It also assumes the AEL maintains continuous insulation throughout all operating conditions, using a fixed insulation coefficient. In reality, the rise and fall of AEL temperature is a process, not a step change. When the AEL transitions to a thermal standby state, there is a natural temperature decay process, and it does not require heating before reaching the predetermined temperature. Therefore, the AEL's insulation time is shorter than its thermal standby time, resulting in less heat required for insulation. Furthermore, if the AEL transitions to operating mode before its temperature decays to the predetermined temperature for thermal standby, the amount of heat required to reach the operating temperature will be lower. Therefore, ignoring the dynamic temperature change of the AEL ultimately leads to an increase in the thermal storage capacity configuration.

[0005] Furthermore, existing solutions set fixed interaction intervals for different operating scenarios to enable simultaneous operation of both electrochemical and hydrogen storage, and the proposed energy management strategy uses a fixed hydrogen production efficiency and ignores the AEL ramping constraint. In reality, offshore wind power fluctuations are highly random, and the amount of fluctuation that needs to be smoothed varies daily. Within the fixed interaction interval, the two energy storage systems operate simultaneously according to a set complementary strategy to enhance the smoothing effect. However, in scenarios with severe fluctuations, the electrochemical storage may over-discharge due to the untimely activation of AEL and PEMFC, resulting in insufficient capacity to accommodate subsequent sudden high-power fluctuations, ultimately requiring increased capacity. In addition, the hydrogen production efficiency of AEL is affected by both input power and temperature. Ramping constraints limit the rapid power increase and subsequent forced power reduction of AEL, thus limiting its peak power and reducing the smoothing effect. Therefore, if ramp-up constraints are ignored when formulating energy management strategies, the AEL cannot operate at a high power level for an extended period. At the same temperature, this state has the highest hydrogen production efficiency. In summary, ignoring the above characteristics means that the proposed strategy requires increasing the capacity of other equipment to compensate for the shortcomings of the AEL, thereby increasing the capacity configuration cost. Summary of the Invention

[0006] The purpose of this invention is to address the technical problem that existing hybrid electric-hydrogen-thermal energy storage systems for mitigating wind power fluctuations do not consider AEL temperature variations and do not adequately consider daily offshore wind power variations and AEL operating characteristics when formulating energy management strategies, resulting in poor capacity configuration. The invention provides a capacity configuration method for hybrid electric-hydrogen-thermal energy storage based on dynamic interaction intervals to mitigate offshore wind fluctuations.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for configuring the capacity of an electro-hydrogen-thermal hybrid energy storage system to mitigate ocean wind fluctuations includes the following steps: Step 1: Construct a dynamic temperature model for the alkaline electrolyzer (AEL). This model is used to characterize the thermal state evolution of the AEL under varying operating conditions. Step 2: Based on the dynamic temperature model, and combined with the preset thermal safety threshold and minimum continuous operating time, formulate the AEL self-insulating operation strategy; Step 3: Based on the daily fluctuations in offshore wind power and the availability of thermal state that the AEL self-insulation strategy can maintain, construct a dynamic interaction interval model to determine the collaborative action boundary between electrical energy storage and hydrogen energy storage. Step 4: Based on the dynamic interaction range constructed in Step 3, construct an energy management strategy for the hybrid energy storage system; Step 5: Based on the dynamic temperature model in Step 1, the AEL self-insulation strategy in Step 2, the dynamic interaction interval model in Step 3, and the energy management strategy in Step 4, construct a capacity configuration optimization model for the electric-hydrogen-thermal hybrid energy storage system. With the minimum annualized total cost as the objective function, and the constraints of meeting the wind power fluctuation smoothing requirements, AEL thermal safety constraints, upper and lower limits of energy storage equipment capacity, and power coupling relationship within the dynamic interaction interval, solve for the optimal rated capacity of electric energy storage, hydrogen energy storage, and thermal energy storage, and construct a capacity configuration evaluation model.

[0008] The dynamic temperature model constructed in step 1 is as follows: (1); In the formula: and The first i sky t Time and t AEL temperature at +1 moment; For time step; and These are the equivalent thermal capacitance and thermal resistance of AEL, respectively; These are the fitting parameters; , and Each of the AEL numbers i sky t The power generated at all times, the power lost in heat, and the power exchanged with the thermal storage system.

[0009] In dynamic temperature models, heat generation power models for: (2); In the formula: , and These are the fitting parameters; For the first i sky t The per-unit value of the input power at time AEL; For the first i sky t Input power of AEL at time; In equation (2), the per-unit model of input power is: (3); In the formula: This is the rated power of AEL.

[0010] In dynamic temperature models, heat loss power models for: (4); In the formula: For the first i sky t The ambient temperature of AEL at any given time.

[0011] In step 2, based on the AEL dynamic temperature model and input power per-unit model constructed in step 1, an AEL hydrogen production efficiency model is constructed, as follows: (5); (6); In the formula: Use 0-1 variables to enable / disable AEL; For the first i sky t AEL hydrogen production efficiency at any given time; For the first i sky t AEL hydrogen production power at any given time; AEL generates heat during hydrogen production. If this heat is sufficient to meet the AEL's own temperature requirements, the excess heat is stored in a heat storage tank; otherwise, the heat storage tank needs to provide the heat. Therefore, the AEL self-insulating model can be expressed by formula (7): (7); In the formula: and The first i sky t Time and t At time -1, the thermal storage tank stores heat. For heat exchanger efficiency; , and The first i sky tAt any given moment, the AEL, proton exchange membrane fuel cell (PEMFC), and waste heat generation equipment transfer heat power to the heat storage tank; For the first i sky t The system's heat consumption at all times; and These are the power generation and heating efficiencies of PEMFC and abandoned power generation heating equipment, respectively. and The first i sky t Input power of PEMFC and abandoned power heating equipment at all times; For the first i sky t The thermal storage tank continuously transfers heat power to the AEL; and These are the thermal insulation coefficient and rated power of PEMFC, respectively.

[0012] Step 2 includes the following steps: Sub-step 2.1: According to equation (1), calculate the temperature of AEL at the next moment when the thermal storage system does not participate in AEL insulation. ; Sub-step 2.2: According to equation (5), the hydrogen production efficiency of the AEL is positively correlated with temperature. The higher the hydrogen production efficiency, the better the performance in smoothing wind power fluctuations. Therefore, when the AEL is working, its temperature should be rapidly raised to the rated temperature. In addition, the AEL should respond quickly when participating in smoothing wind power fluctuations, so a minimum temperature should be set to keep it in a hot standby state when it is not working. Therefore, and lowest temperature Rated temperature The magnitudes of the two are compared to determine the heat interaction between the AEL and the thermal storage system. Case 1) If If the AEL temperature drops below the minimum required level, intervention is necessary. Therefore, determine the AEL's operating status: If... This indicates that AEL is not working and heating must be activated to maintain it in a hot standby state. Therefore, according to formula (1), calculate... Required thermal power And heat it up, at this time , ;like This indicates that AEL is in operation and needs to be maintained and heated to the rated temperature to improve its hydrogen production efficiency. The heat is provided by thermal storage. Therefore, according to formula (1), the required [temperature] is calculated. Thermal power ,at this time , ; This operation prevents the AEL from failing to quickly meet the requirements for smoothing wind power fluctuations due to low temperature causing electrolyte freezing, catalyst failure, or cold start. Case 2) If If the temperature is within a safe range, then determine the AEL operating status: If This indicates that the device is not in use and does not require insulation, therefore it will not be updated. ,at this time ;like Then, based on equation (1), the judgment is made. Required thermal power ,at this time , ; Case 3) If This indicates that AEL has residual heat after meeting its own temperature requirements. This residual heat needs to be transferred to the heat storage tank for preservation. Therefore, the temperature is calculated. Greater than Partial heat power ,at this time Limit the temperature to ;and , .

[0013] In step 3, a dynamic interaction interval model is constructed, which includes the following sub-steps: Sub-step 3-1) Obtain the normalized power standard deviation of offshore wind power and the maximum rise and fall rates of wind power: (8); In the formula: and The first i Standard deviation of offshore wind power and its normalized value; The total number of hours in a day; For the first i sky t Real-time offshore wind power output; For the first i Average power output of offshore wind power in the sky; and The first i Maximum and minimum wind power output in the sky and offshore areas; and The first i Maximum rising and falling power of offshore wind power; and The first i Normalized rise and fall power of offshore and in-flight wind power; Sub-step 3.2) Based on the calculation results of sub-step 3.1), and combined with the AEL thermal state availability and time-series response capability determined by the AEL self-insulating strategy, a dynamic interaction interval model is constructed using formula (9): (9); In the formula: and The first i The dynamic interaction range between TianAEL and PEMFC; and The first i Dynamic interaction range boundaries between TianAEL and PEMFC; , , , , and These are the dynamic interaction interval weights for AEL and PEMFC, respectively.

[0014] The purpose of this operation is to dynamically set the interaction range according to the daily wind power fluctuations, so that the state of charge (SOC) of the electric energy storage will activate the AEL before it reaches the upper limit and the PEMFC before it reaches the lower limit. This can significantly improve the operating time and smoothing performance of the hydrogen storage system, and keep the SOC at an intermediate level, leaving sufficient capacity and space to cope with subsequent large power fluctuations.

[0015] In step 4, based on the dynamic interaction interval proposed in step 3, an energy management strategy is constructed, which includes the following sub-steps: Sub-step 4.1) Assume that electrochemical energy storage is in the first... i sky t Power at time Specifically, if it is charging, it is indicated as If it discharges, it is represented as Power to be leveled And the remaining power to be mitigated after the first power allocation Positive and negative fluctuations are addressed separately. Positive fluctuations are mitigated by charging electrochemical energy storage, starting up AEL (Automatic Energy Source) hydrogen production, and activating surplus power for heat generation. Negative fluctuations are mitigated by discharging hydrogen using PEMFC (Power Equipped Momentum Controller) and electrochemical energy storage. The thermal storage system is only used when the power to be mitigated is at its maximum. Furthermore, the electric-hydrogen hybrid energy storage system will only participate in the smoothing process if there is still residual power to be smoothed after the smoothing process is completed; i sky t The maximum and minimum values ​​of AEL at time t are respectively under the ramp constraint. and ,at the same time It needs to be greater than 0; the input power of the AEL can reach 120% of the rated power, but there may be an explosion risk when its input power is less than 20% of the rated power. Therefore, it is necessary to avoid the AEL operating in this power range; if there is still residual power to be smoothed after all equipment in the electro-hydrogen-thermal hybrid energy storage system has been smoothed, it is considered as a shortfall. Sub-step 4.2) If the conditions shown in formula (10) are met, then AEL should be smoothed out as much as possible under the ramping constraint; if there is a remainder after AEL smoothing out, then the electrochemical energy storage will only participate in smoothing out when it was discharging or not working at the previous moment; at the same time, it should be noted that if To avoid AEL operating at low power, then Electrochemical energy storage discharge compensation AEL over-smoothing component: (10); In the formula: For the first i sky t The state of charge of electrochemical energy storage at any given moment; This represents the maximum value of the electrochemical energy storage state of charge. For the first i sky t The hydrogen storage status of the hydrogen storage tank at all times; This represents the maximum value of the hydrogen storage state in the hydrogen storage tank.

[0016] Sub-step 4.3: If the conditions shown in formula (11) are met, the energy management strategy is as follows: (11); In the formula: Minimum state of charge in electrochemical energy storage.

[0017] Case 1) If So, AEL only works in the previous period of time, that is At that time, AEL press and The maximum value participates in the smoothing, and the electrochemical energy storage smooths the remaining fluctuations. In addition, it should be noted that if there is an AEL over-compensation, the electrochemical energy storage needs to discharge to compensate for the over-smoothed part of the AEL. Case 2) If At this point, AEL presses first. and The maximum value participates in the smoothing process, and electrochemical energy storage compensates for the remaining portion; if there is still a surplus after the first power distribution, then only... Then, the power is redistributed again to AEL; Sub-step 4.4: If the conditions shown in formula (12) are met, the energy management strategy includes the following steps: (12); In the formula: Minimum hydrogen storage capacity of the hydrogen storage tank.

[0018] Case 1) If the electrochemical energy storage discharged at the previous moment, i.e. At this time, the electrochemical energy storage does not activate, and the PEMFC operates at its rated power. If there is overcompensation, the electrochemical energy storage will be charged. Scenario 2) If the electrochemical energy storage was charging or not working at the previous moment, i.e. And PEMFC worked in the previous moment, that is In this case, the electrochemical energy storage will not activate, and the PEMFC will operate at its rated power. If there is overcompensation, the electrochemical energy storage will be charged. Scenario 3) If the electrochemical energy storage was charging or not working at the previous moment, i.e. And PEMFC was not working at the previous moment, that is In this case, the electrochemical energy storage will first smooth out the power. If there is still power to be smoothed out after smoothing out the power, the PEMFC will be started again to smooth out the power.

[0019] Sub-step 4.5: If the situation shown in formula (13) is satisfied, then the electrochemical energy storage will first be smoothed out. If there is still power to be smoothed out after smoothing out, then PEMFC will participate in the smoothing out. (13).

[0020] In step 5, the objective function for configuring the capacity of the hybrid electric-hydrogen-thermal energy storage system to mitigate ocean wind fluctuations is constructed, which includes the following sub-steps: Sub-step 5.1: Based on formula (14), construct the overall objective function for the capacity configuration of the hybrid electric-hydrogen-thermal energy storage to mitigate sea wind fluctuations, as follows: (14); In the formula: Configure annualized total cost for capacity; , , and These are the total cost of electrochemical energy storage configuration, the total cost of hydrogen storage system configuration, the total cost of thermal storage system configuration, and the cost of wind curtailment penalty; This represents all decision variables during the planning phase.

[0021] Sub-step 5.2: Based on formulas (15)-(18), construct the total cost function for electrochemical energy storage configuration, as follows: (15); (16); (17); (18); In the formula: and These are the investment cost and operating cost of electrochemical energy storage, respectively. and These are the unit power and capacity configuration costs of electrochemical energy storage, respectively. and Rated power and capacity of electrochemical energy storage; The discount rate; For the planning period; Unit maintenance cost for electrochemical energy storage; Costs associated with the degradation of electrochemical energy storage; The electrochemical energy storage lifespan degradation rate; The planned lifespan for electrochemical energy storage; Cost per unit lifetime decay of electrochemical energy storage.

[0022] Sub-step 5.3: Based on formulas (19)-(21), construct the total cost function for configuring the hydrogen storage system, as follows: (19); (20); (twenty one); In the formula: and These are the investment cost and operating cost of the hydrogen storage system, respectively. and The unit power configuration cost for AEL and PEMFC are respectively; Unit capacity configuration cost of hydrogen storage tanks; This refers to the rated capacity of the hydrogen storage tank. Unit maintenance cost of hydrogen storage system; Costs associated with the degradation of hydrogen storage systems; For start-up and shutdown costs; This refers to the number of times an AEL is started and stopped within one cycle. and These represent the total number of days in the plan and the total number of hours in a cycle, respectively. Sub-step 5.4: Considering the life decay of AEL under three typical operating conditions—stable operation, fluctuating operation, and hot standby—a life decay model of AEL is constructed based on formulas (22)-(26), as follows: (twenty two); (twenty three); (twenty four); (25); (26); In the formula: , and The first i sky t Efficiency degradation of AEL under stable operation, fluctuating operation and hot standby conditions at all times; , and The first i sky t Efficiency attenuation coefficient of AEL under stable operation, fluctuating operation and hot standby conditions at any time; For the first i sky t AEL input power at time -1; and These represent the total efficiency decay and the total equivalent lifetime decay of AEL per day, respectively. and These are the rated and maximum hydrogen production efficiencies of the AEL, respectively. and These are the rated degradation coefficient and rated operating life of AEL hydrogen production efficiency, respectively.

[0023] Sub-step 5.5: Based on formulas (27)-(30), construct the total cost function for configuring the thermal storage system, as follows: (27); (28); (29); (30); In the formula: and These are the investment cost and operating cost of the thermal storage system, respectively. and The unit power configuration cost for heat exchangers and abandoned power generation heating, respectively; Unit capacity configuration cost of thermal storage tanks; and These are the rated power of the heat exchanger and the power curtailment heating, respectively. This refers to the rated capacity of the thermal storage tank. Unit maintenance cost of the thermal storage system; Costs associated with the degradation of thermal storage systems; The lifespan degradation rate of the thermal storage system; The planned lifespan of the thermal storage system; Cost per unit lifespan decay of the thermal storage system.

[0024] Sub-step 5.6: Based on formula (31), construct the wind curtailment penalty cost function, as follows: (31); In the formula: Penalty cost per unit; and The first i sky t Positive and negative deficits at all times.

[0025] Sub-step 5.7: Constructing capacity configuration constraints for hybrid electric-hydrogen-thermal energy storage to mitigate ocean wind fluctuations, specifically including the following sub-steps: Sub-step 5.7.1: Construct power balance constraints based on formula (32), as follows: (32); In the formula: and The first i sky t The constant electrochemical energy storage charging and discharging power.

[0026] Sub-step 5.7.2: Construct electrochemical energy storage power capacity constraints based on formulas (33)-(34), as follows: (33); (34); In the formula: For the first i sky t Electrochemical energy storage state of charge at time -1; This refers to the electrochemical energy storage conversion efficiency.

[0027] Sub-step 5.7.3: AEL can operate at 20% above the rated power, but there is an explosion risk when operating below 20% of the rated power. Therefore, the power capacity constraint of the hydrogen storage system is constructed based on formulas (35)-(36), as follows: (35); (36); In the formula: For the first i sky t -1 is the hydrogen storage state SOHC; and These are the hydrogen density and lower calorific value of the hydrogen storage tank, respectively.

[0028] Sub-step 5.7.4: Construct the power capacity constraint of the hydrogen storage system based on formulas (37)-(38), as follows: (37); (38); Constructing a capacity allocation evaluation model includes the following sub-steps: Sub-step (1) In order to analyze the quality of capacity configuration results more comprehensively, a capacity configuration evaluation model is constructed. Since there are both optimistic and pessimistic indicators, according to formula (39), the scoring methods for each indicator are as follows: (39); In the formula: For the first i The first configuration j The assigned scores for each indicator; No. i The first configuration j The original values ​​of each indicator.

[0029] Sub-step (2) Based on formula (40), construct the comprehensive evaluation index scoring method as follows: (40); In the formula: For the first i The overall score under this configuration The total number of indicators; For the first j The weight of each indicator.

[0030] This invention also includes a self-heating operation method for alkaline electrolyzers (AELs). Based on a dynamic temperature model and combined with a preset thermal safety threshold and minimum continuous operating time, an AEL self-heating operation strategy is formulated, including the following steps: Step 1: Calculate the temperature of the AEL at the next moment when the thermal storage system does not participate in the AEL insulation. ; Step 2: and lowest temperature Rated temperature The two values ​​are compared to determine the heat interaction between AEL and the thermal storage system.

[0031] In step 2, specifically: Case 1) If If the AEL temperature drops below the minimum required level, intervention is necessary. Therefore, determine the AEL's operating status: If... This indicates that AEL is not working and heating must be activated to maintain it in a hot standby state. Calculation Required thermal power And heat it up, at this time , ;like This indicates that the AEL is operating and needs to be kept running and heated to its rated temperature to improve its hydrogen production efficiency. The heat is provided by thermal storage. Calculations show the required... Thermal power ,at this time , ; This operation prevents the AEL from failing to quickly meet the requirements for smoothing wind power fluctuations due to low temperature causing electrolyte freezing, catalyst failure, or cold start. Case 2) If If the temperature is within a safe range, then determine the AEL operating status: If This indicates that the device is not in use and does not require insulation, therefore it will not be updated. ,at this time ;like ,judge Required thermal power ,at this time , ; Case 3) If This indicates that AEL has residual heat after meeting its own temperature requirements. This residual heat needs to be transferred to the heat storage tank for preservation. Therefore, the temperature is calculated. Greater than Partial heat power ,at this time Limit the temperature to ;and , .

[0032] The dynamic temperature model is specifically as follows: (1); In the formula: and The first i sky t Time and t AEL temperature at +1 moment; For time step; and These are the equivalent thermal capacitance and thermal resistance of AEL, respectively; These are the fitting parameters; , and Each of the AEL numbers i sky t The power generated at all times, the power lost in heat, and the power exchanged with the thermal storage system.

[0033] In dynamic temperature models, heat generation power models for: (2); In the formula: , and These are the fitting parameters; For the first i sky t The per-unit value of the input power at time AEL; For the first i sky t Input power of AEL at time; In equation (2), the per-unit model of input power is: (3); In the formula: This is the rated power of AEL.

[0034] In dynamic temperature models, heat loss power models for: (4); In the formula: For the first i sky t The ambient temperature of AEL at any given time.

[0035] Based on the constructed AEL dynamic temperature model and input power per-unit model, an AEL hydrogen production efficiency model is constructed as follows: (5); (6); In the formula: Use 0-1 variables to enable / disable AEL; For the first i sky t AEL hydrogen production efficiency at any given time; For the first i sky t AEL hydrogen production power at any given time; AEL generates heat during hydrogen production. If this heat is sufficient to meet the AEL's own temperature requirements, the excess heat is stored in a heat storage tank; otherwise, the heat storage tank needs to provide the heat. Therefore, the AEL self-insulating model can be expressed by formula (7): (7); In the formula: and The first i sky t Time and t At time -1, the thermal storage tank stores heat. For heat exchanger efficiency; , and The first i sky t At any given moment, the AEL, proton exchange membrane fuel cell (PEMFC), and waste heat generation equipment transfer heat power to the heat storage tank; For the first i sky t The system's heat consumption at all times; and These are the power generation and heating efficiencies of PEMFC and abandoned power generation heating equipment, respectively. and The first i sky t Input power of PEMFC and abandoned power heating equipment at all times; For the first i sky t The thermal storage tank continuously transfers heat power to the AEL; and These are the thermal insulation coefficient and rated power of PEMFC, respectively.

[0036] In step 1, according to equation (1), the temperature of AEL at the next moment is calculated when the thermal storage system does not participate in AEL insulation. ; In step 2, according to equation (5), the hydrogen production efficiency of the AEL is positively correlated with temperature. The higher the hydrogen production efficiency, the better the performance in smoothing wind power fluctuations. Therefore, the temperature of the AEL should be rapidly raised to the rated temperature when it is working. In addition, the AEL should respond quickly when participating in smoothing wind power fluctuations, so a minimum temperature should be set to keep it in a hot standby state when it is not working. Therefore, and lowest temperature Rated temperature The two values ​​are compared to determine the heat interaction between AEL and the thermal storage system.

[0037] Compared with the prior art, the present invention has the following technical effects: 1) This invention constructs a self-insulating model and strategy that takes into account the temperature requirements of AEL, characterizes the dynamic changes of AEL temperature, and explores the marginal heat required for AEL insulation and the hybrid energy storage capacity of electro-hydrogen-thermal energy. 2) This invention takes into account the fluctuations in offshore wind power on the same day and provides a dynamic interaction range to adjust the complementary range of electrochemical energy storage and hydrogen storage systems. Based on this, it integrates the high and low power operation characteristics, ramping constraints, and energy consumption characteristics of the AEL and proposes an energy management strategy to give full play to the smoothing performance of the hydrogen storage system and leave enough room for the electrochemical energy storage system to cope with subsequent fluctuations, ultimately achieving the goal of reducing the configuration cost of the electro-hydrogen-thermal hybrid energy storage capacity. Attached Figure Description

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a framework diagram of the electro-hydrogen-thermal hybrid energy storage system in this invention; Figure 2 This is a flowchart illustrating the solution process for the capacity configuration of the hybrid electric-hydrogen-thermal energy storage system for mitigating sea wind fluctuations in this invention. Figure 3 This is a comparison chart of smoothed power fluctuations in methods 2 and 3 of this invention on a typical day 4; Figure 4 This is a graph showing the results of Method 2 in this invention on a typical day 4; Figure 5 This is a graph showing the results of method 3 in this invention on a typical day 4; Figure 6 This is a comparison chart of the state of charge and hydrogen storage state of methods 2 and 3 in this invention on a typical day 4. Figure 7 This is an evaluation diagram of the capacity configuration results of methods 1, 2 and 3 in this invention. Detailed Implementation

[0039] like Figure 1 As shown, a method for configuring the capacity of an electro-hydrogen-thermal hybrid energy storage system to mitigate ocean wind fluctuations includes the following steps: Step 1: Construct a dynamic temperature model for the alkaline electrolyzer (AEL). This model is used to characterize the thermal state evolution of the AEL under varying operating conditions. Step 2: Based on the dynamic temperature model, and combined with the preset thermal safety threshold and minimum continuous operating time, formulate the AEL self-insulating operation strategy; Step 3: Based on the daily fluctuations in offshore wind power and the availability of thermal state that the AEL self-insulation strategy can maintain, construct a dynamic interaction interval model to determine the collaborative action boundary between electrical energy storage and hydrogen energy storage. Step 4: Based on the dynamic interaction range constructed in Step 3, construct an energy management strategy for the hybrid energy storage system; Step 5: Based on the dynamic temperature model in Step 1, the AEL self-insulation strategy in Step 2, the dynamic interaction interval model in Step 3, and the energy management strategy in Step 4, construct a capacity configuration optimization model for the electric-hydrogen-thermal hybrid energy storage system. With the minimum annualized total cost as the objective function, and the constraints of meeting the wind power fluctuation smoothing requirements, AEL thermal safety constraints, upper and lower limits of energy storage equipment capacity, and power coupling relationship within the dynamic interaction interval, solve for the optimal rated capacity of electric energy storage, hydrogen energy storage, and thermal energy storage, and construct a capacity configuration evaluation model.

[0040] The dynamic temperature model constructed in step 1 is as follows: (1); In the formula: and The first i sky t Time and t AEL temperature at +1 moment; For time step; and These are the equivalent thermal capacitance and thermal resistance of AEL, respectively; These are the fitting parameters; , and Each of the AEL numbers i sky t The power generated at all times, the power lost in heat, and the power exchanged with the thermal storage system.

[0041] In dynamic temperature models, heat generation power models for: (2); In the formula: , and These are the fitting parameters; For the first i sky t The per-unit value of the input power at time AEL; For the first i sky t Input power of AEL at time; In equation (2), the per-unit model of input power is: (3); In the formula: This is the rated power of AEL.

[0042] In dynamic temperature models, heat loss power models for: (4); In the formula: For the first i sky t The ambient temperature of AEL at any given time.

[0043] In step 2, based on the AEL dynamic temperature model and input power per-unit model constructed in step 1, an AEL hydrogen production efficiency model is constructed, as follows: (5); (6); In the formula: Use 0-1 variables to enable / disable AEL; For the first i sky t AEL hydrogen production efficiency at any given time; For the first i sky t AEL hydrogen production power at any given time; AEL generates heat during hydrogen production. If this heat is sufficient to meet the AEL's own temperature requirements, the excess heat is stored in a heat storage tank; otherwise, the heat storage tank needs to provide the heat. Therefore, the AEL self-insulating model can be expressed by formula (7): (7); In the formula: and The first i sky t Time and t At time -1, the thermal storage tank stores heat. For heat exchanger efficiency; , and The first i sky t At any given moment, the AEL, proton exchange membrane fuel cell (PEMFC), and waste heat generation equipment transfer heat power to the heat storage tank; For the first i sky t The system's heat consumption at all times; and These are the power generation and heating efficiencies of PEMFC and abandoned power generation heating equipment, respectively. and The first i sky t Input power of PEMFC and abandoned power heating equipment at all times; For the first i sky t The thermal storage tank continuously transfers heat power to the AEL; and These are the thermal insulation coefficient and rated power of PEMFC, respectively.

[0044] Step 2 includes the following steps: Sub-step 2.1: According to equation (1), calculate the temperature of AEL at the next moment when the thermal storage system does not participate in AEL insulation. ; Sub-step 2.2: According to equation (5), the hydrogen production efficiency of the AEL is positively correlated with temperature. The higher the hydrogen production efficiency, the better the performance in smoothing wind power fluctuations. Therefore, when the AEL is working, its temperature should be rapidly raised to the rated temperature. In addition, the AEL should respond quickly when participating in smoothing wind power fluctuations, so a minimum temperature should be set to keep it in a hot standby state when it is not working. Therefore, and lowest temperature Rated temperature The magnitudes of the two are compared to determine the heat interaction between the AEL and the thermal storage system. Case 1) If If the AEL temperature drops below the minimum required level, intervention is necessary. Therefore, determine the AEL's operating status: If... This indicates that AEL is not working and heating must be activated to maintain it in a hot standby state. Therefore, according to formula (1), calculate... Required thermal power And heat it up, at this time , ;like This indicates that AEL is in operation and needs to be maintained and heated to the rated temperature to improve its hydrogen production efficiency. The heat is provided by thermal storage. Therefore, according to formula (1), the required [temperature] is calculated. Thermal power ,at this time , ; This operation prevents the AEL from failing to quickly meet the requirements for smoothing wind power fluctuations due to low temperature causing electrolyte freezing, catalyst failure, or cold start. Case 2) If If the temperature is within a safe range, then determine the AEL operating status: If This indicates that the device is not in use and does not require insulation, therefore it will not be updated. ,at this time ;like Then, based on equation (1), the judgment is made. Required thermal power ,at this time , ; Case 3) If This indicates that AEL has residual heat after meeting its own temperature requirements. This residual heat needs to be transferred to the heat storage tank for preservation. Therefore, the temperature is calculated. Greater than Partial heat power ,at this time Limit the temperature to ;and , .

[0045] In step 3, a dynamic interaction interval model is constructed, which includes the following sub-steps: Sub-step 3-1) Obtain the normalized power standard deviation of offshore wind power and the maximum rise and fall rates of wind power: (8); In the formula: and The first i Standard deviation of offshore wind power and its normalized value; The total number of hours in a day; For the first i sky t Real-time offshore wind power output; For the first i Average power output of offshore wind power in the sky; and The first i Maximum and minimum wind power output in the sky and offshore areas; and The first i Maximum rising and falling power of offshore wind power; and The first i Normalized rise and fall power of offshore and in-flight wind power; Sub-step 3.2) Based on the calculation results of sub-step 3.1), and combined with the AEL thermal state availability and time-series response capability determined by the AEL self-insulating strategy, a dynamic interaction interval model is constructed using formula (9): (9); In the formula: and The first i The dynamic interaction range between TianAEL and PEMFC; and The first i Dynamic interaction range boundaries between TianAEL and PEMFC; , , , , and These are the dynamic interaction interval weights for AEL and PEMFC, respectively.

[0046] The purpose of this operation is to dynamically set the interaction range according to the daily wind power fluctuations, so that the state of charge (SOC) of the electric energy storage will activate the AEL before it reaches the upper limit and the PEMFC before it reaches the lower limit. This can significantly improve the operating time and smoothing performance of the hydrogen storage system, and keep the SOC at an intermediate level, leaving sufficient capacity and space to cope with subsequent large power fluctuations.

[0047] In step 4, based on the dynamic interaction interval proposed in step 3, an energy management strategy is constructed, which includes the following sub-steps: Sub-step 4.1) Assume that electrochemical energy storage is in the first... i sky t Power at time Specifically, if it is charging, it is indicated as If it discharges, it is represented as Power to be leveled And the remaining power to be mitigated after the first power allocation Positive and negative fluctuations are addressed separately. Positive fluctuations are mitigated by charging electrochemical energy storage, starting up AEL (Automatic Energy Source) hydrogen production, and activating surplus power for heat generation. Negative fluctuations are mitigated by discharging hydrogen using PEMFC (Power Equipped Momentum Controller) and electrochemical energy storage. The thermal storage system is only used when the power to be mitigated is at its maximum. Furthermore, the electric-hydrogen hybrid energy storage system will only participate in the smoothing process if there is still residual power to be smoothed after the smoothing process is completed; i sky t The maximum and minimum values ​​of AEL at time t are respectively under the ramp constraint. and ,at the same time It needs to be greater than 0; the input power of the AEL can reach 120% of the rated power, but there may be an explosion risk when its input power is less than 20% of the rated power. Therefore, it is necessary to avoid the AEL operating in this power range; if there is still residual power to be smoothed after all equipment in the electro-hydrogen-thermal hybrid energy storage system has been smoothed, it is considered as a shortfall. Sub-step 4.2) If the conditions shown in formula (10) are met, then AEL should be smoothed out as much as possible under the ramping constraint; if there is a remainder after AEL smoothing out, then the electrochemical energy storage will only participate in smoothing out when it was discharging or not working at the previous moment; at the same time, it should be noted that if To avoid AEL operating at low power, then Electrochemical energy storage discharge compensation AEL over-smoothing component: (10); In the formula: For the first i sky t The state of charge of electrochemical energy storage at any given moment; This represents the maximum value of the electrochemical energy storage state of charge. For the first i sky t The hydrogen storage status of the hydrogen storage tank at all times; This represents the maximum value of the hydrogen storage state in the hydrogen storage tank.

[0048] Sub-step 4.3: If the conditions shown in formula (11) are met, the energy management strategy is as follows: (11); In the formula: Minimum state of charge in electrochemical energy storage.

[0049] Case 1) If So, AEL only works in the previous period of time, that is At that time, AEL press and The maximum value participates in the smoothing, and the electrochemical energy storage smooths the remaining fluctuations. In addition, it should be noted that if there is an AEL over-compensation, the electrochemical energy storage needs to discharge to compensate for the over-smoothed part of the AEL. Case 2) If At this point, AEL presses first. and The maximum value participates in the smoothing process, and electrochemical energy storage compensates for the remaining portion; if there is still a surplus after the first power distribution, then only... Then, the power is redistributed again to AEL; Sub-step 4.4: If the conditions shown in formula (12) are met, the energy management strategy includes the following steps: (12); In the formula: Minimum hydrogen storage capacity of the hydrogen storage tank.

[0050] Case 1) If the electrochemical energy storage discharged at the previous moment, i.e. At this time, the electrochemical energy storage does not activate, and the PEMFC operates at its rated power. If there is overcompensation, the electrochemical energy storage will be charged. Scenario 2) If the electrochemical energy storage was charging or not working at the previous moment, i.e. And PEMFC worked in the previous moment, that is In this case, the electrochemical energy storage will not activate, and the PEMFC will operate at its rated power. If there is overcompensation, the electrochemical energy storage will be charged. Scenario 3) If the electrochemical energy storage was charging or not working at the previous moment, i.e. And PEMFC was not working at the previous moment, that is In this case, the electrochemical energy storage will first smooth out the power. If there is still power to be smoothed out after smoothing out the power, the PEMFC will be started again to smooth out the power.

[0051] Sub-step 4.5: If the situation shown in formula (13) is satisfied, then the electrochemical energy storage will first be smoothed out. If there is still power to be smoothed out after smoothing out, then PEMFC will participate in the smoothing out. (13).

[0052] In step 5, the objective function for configuring the capacity of the hybrid electric-hydrogen-thermal energy storage system to mitigate ocean wind fluctuations is constructed, which includes the following sub-steps: Sub-step 5.1: Based on formula (14), construct the overall objective function for the capacity configuration of the hybrid electric-hydrogen-thermal energy storage to mitigate sea wind fluctuations, as follows: (14); In the formula: Configure annualized total cost for capacity; , , and These are the total cost of electrochemical energy storage configuration, the total cost of hydrogen storage system configuration, the total cost of thermal storage system configuration, and the cost of wind curtailment penalty; This represents all decision variables during the planning phase.

[0053] Sub-step 5.2: Based on formulas (15)-(18), construct the total cost function for electrochemical energy storage configuration, as follows: (15); (16); (17); (18); In the formula: and These are the investment cost and operating cost of electrochemical energy storage, respectively. and These are the unit power and capacity configuration costs of electrochemical energy storage, respectively. and Rated power and capacity of electrochemical energy storage; The discount rate; For the planning period; Unit maintenance cost for electrochemical energy storage; Costs associated with the degradation of electrochemical energy storage; The electrochemical energy storage lifespan degradation rate; The planned lifespan for electrochemical energy storage; Cost per unit lifetime decay of electrochemical energy storage.

[0054] Sub-step 5.3: Based on formulas (19)-(21), construct the total cost function for configuring the hydrogen storage system, as follows: (19); (20); (twenty one); In the formula: and These are the investment cost and operating cost of the hydrogen storage system, respectively. and The unit power configuration cost for AEL and PEMFC are respectively; Unit capacity configuration cost of hydrogen storage tanks; This refers to the rated capacity of the hydrogen storage tank. Unit maintenance cost of hydrogen storage system; Costs associated with the degradation of hydrogen storage systems; For start-up and shutdown costs; This refers to the number of times an AEL is started and stopped within one cycle. and These represent the total number of days in the plan and the total number of hours in a cycle, respectively. Sub-step 5.4: Considering the life decay of AEL under three typical operating conditions—stable operation, fluctuating operation, and hot standby—a life decay model of AEL is constructed based on formulas (22)-(26), as follows: (twenty two); (twenty three); (twenty four); (25); (26); In the formula: , and The first i sky t Efficiency degradation of AEL under stable operation, fluctuating operation and hot standby conditions at all times; , and The first i sky t Efficiency attenuation coefficient of AEL under stable operation, fluctuating operation and hot standby conditions at any time; For the first i sky t AEL input power at time -1; and These represent the total efficiency decay and the total equivalent lifetime decay of AEL per day, respectively. and These are the rated and maximum hydrogen production efficiencies of the AEL, respectively. and These are the rated degradation coefficient and rated operating life of AEL hydrogen production efficiency, respectively.

[0055] Sub-step 5.5: Based on formulas (27)-(30), construct the total cost function for configuring the thermal storage system, as follows: (27); (28); (29); (30); In the formula: and These are the investment cost and operating cost of the thermal storage system, respectively. and The unit power configuration cost for heat exchangers and abandoned power generation heating, respectively; Unit capacity configuration cost of thermal storage tanks; and These are the rated power of the heat exchanger and the power curtailment heating, respectively. This refers to the rated capacity of the thermal storage tank. Unit maintenance cost of the thermal storage system; Costs associated with the degradation of thermal storage systems; The lifespan degradation rate of the thermal storage system; The planned lifespan of the thermal storage system; Cost per unit lifespan decay of the thermal storage system.

[0056] Sub-step 5.6: Based on formula (31), construct the wind curtailment penalty cost function, as follows: (31); In the formula: Penalty cost per unit; and The first i sky t Positive and negative deficits at all times.

[0057] Sub-step 5.7: Constructing capacity configuration constraints for hybrid electric-hydrogen-thermal energy storage to mitigate ocean wind fluctuations, specifically including the following sub-steps: Sub-step 5.7.1: Construct power balance constraints based on formula (32), as follows: (32); In the formula: and The first i sky t The constant electrochemical energy storage charging and discharging power.

[0058] Sub-step 5.7.2: Construct electrochemical energy storage power capacity constraints based on formulas (33)-(34), as follows: (33); (34); In the formula: For the first i sky t Electrochemical energy storage state of charge at time -1; This refers to the electrochemical energy storage conversion efficiency.

[0059] Sub-step 5.7.3: AEL can operate at 20% above the rated power, but there is an explosion risk when operating below 20% of the rated power. Therefore, the power capacity constraint of the hydrogen storage system is constructed based on formulas (35)-(36), as follows: (35); (36); In the formula: For the first i sky t -1 is the hydrogen storage state SOHC; and These are the hydrogen density and lower calorific value of the hydrogen storage tank, respectively.

[0060] Sub-step 5.7.4: Construct the power capacity constraint of the hydrogen storage system based on formulas (37)-(38), as follows: (37); (38); The construction of the capacity configuration evaluation model includes the following sub-steps: Sub-step (1): In order to analyze the quality of capacity configuration results more comprehensively, a capacity configuration evaluation model is constructed. Since there are both optimistic and pessimistic indicators, according to formula (39), the scoring method for each indicator is as follows: (39); In the formula: For the first i The first configuration j The assigned scores for each indicator; No. i The first configuration j The original values ​​of each indicator.

[0061] Sub-step (2): Based on formula (40), construct the comprehensive evaluation index scoring method, as follows: (40); In the formula: For the first i The overall score under this configuration The total number of indicators; For the first j The weight of each indicator.

[0062] To address the technical issues of existing alkaline electrolyzer AEL self-insulating operation technology neglecting the dynamic process of natural temperature decay under varying operating conditions, and employing a fixed insulation strategy throughout the process leading to an overestimation of heat demand and redundant thermal storage configuration, specifically, existing technologies, when dealing with the thermal state of alkaline electrolyzers under varying operating conditions, do not consider the gradual temperature change and natural decay process, but instead use constant parameters for continuous insulation, resulting in distorted heat demand assessment, excessively large capacity configuration of thermal storage systems (such as heat exchangers and thermal storage tanks), and high investment costs; This invention also includes a self-heating operation method for alkaline electrolyzers (AELs). Based on a dynamic temperature model and combined with a preset thermal safety threshold and minimum continuous operating time, an AEL self-heating operation strategy is formulated, including the following steps: Step 1: Calculate the temperature of the AEL at the next moment when the thermal storage system does not participate in the AEL insulation. ; Step 2: and lowest temperature Rated temperature The two values ​​are compared to determine the heat interaction between AEL and the thermal storage system.

[0063] In step 2, specifically: Case 1) If If the AEL temperature drops below the minimum required level, intervention is necessary. Therefore, determine the AEL's operating status: If... This indicates that AEL is not working and heating must be activated to maintain it in a hot standby state. Therefore, according to formula (1), calculate... Required thermal power And heat it up, at this time , ;like This indicates that AEL is in operation and needs to be maintained and heated to the rated temperature to improve its hydrogen production efficiency. The heat is provided by thermal storage. Therefore, according to formula (1), the required [temperature] is calculated. Thermal power ,at this time , ; This operation prevents the AEL from failing to quickly meet the requirements for smoothing wind power fluctuations due to low temperature causing electrolyte freezing, catalyst failure, or cold start. Case 2) If If the temperature is within a safe range, then determine the AEL operating status: If This indicates that the device is not in use and does not require insulation, therefore it will not be updated. ,at this time ;like Then, based on equation (1), the judgment is made. Required thermal power ,at this time , ; Case 3) If This indicates that AEL has residual heat after meeting its own temperature requirements. This residual heat needs to be transferred to the heat storage tank for preservation. Therefore, the temperature is calculated. Greater than Partial heat power ,at this time Limit the temperature to ;and , .

[0064] The dynamic temperature model is specifically as follows: (1); In the formula: and The first i sky t Time and t AEL temperature at +1 moment; For time step; and These are the equivalent thermal capacitance and thermal resistance of AEL, respectively; These are the fitting parameters; , and Each of the AEL numbers i sky t The power generated at all times, the power lost in heat, and the power exchanged with the thermal storage system.

[0065] In dynamic temperature models, heat generation power models for: (2); In the formula: , and These are the fitting parameters; For the first i sky t The per-unit value of the input power at time AEL; For the first i sky t Input power of AEL at time; In equation (2), the per-unit model of input power is: (3); In the formula: This is the rated power of AEL.

[0066] In dynamic temperature models, heat loss power models for: (4); In the formula: For the first i sky t The ambient temperature of AEL at any given time.

[0067] Based on the constructed AEL dynamic temperature model and input power per-unit model, an AEL hydrogen production efficiency model is constructed as follows: (5); (6); In the formula: Use 0-1 variables to enable / disable AEL; For the first i sky t AEL hydrogen production efficiency at any given time; For the first i sky t AEL hydrogen production power at any given time; AEL generates heat during hydrogen production. If this heat is sufficient to meet the AEL's own temperature requirements, the excess heat is stored in a heat storage tank; otherwise, the heat storage tank needs to provide the heat. Therefore, the AEL self-insulating model can be expressed by formula (7): (7); In the formula: and The first i sky t Time and t At time -1, the thermal storage tank stores heat. For heat exchanger efficiency; , and The first i sky t At any given moment, the AEL, proton exchange membrane fuel cell (PEMFC), and waste heat generation equipment transfer heat power to the heat storage tank; For the firsti sky t The system's heat consumption at all times; and These are the power generation and heating efficiencies of PEMFC and abandoned power generation heating equipment, respectively. and The first i sky t Input power of PEMFC and abandoned power heating equipment at all times; For the first i sky t The thermal storage tank continuously transfers heat power to the AEL; and These are the thermal insulation coefficient and rated power of PEMFC, respectively.

[0068] In step 1, according to equation (1), the temperature of AEL at the next moment is calculated when the thermal storage system does not participate in AEL insulation. ; In step 2, according to equation (5), the hydrogen production efficiency of the AEL is positively correlated with temperature. The higher the hydrogen production efficiency, the better the performance in smoothing wind power fluctuations. Therefore, the temperature of the AEL should be rapidly raised to the rated temperature when it is working. In addition, the AEL should respond quickly when participating in smoothing wind power fluctuations, so a minimum temperature should be set to keep it in a hot standby state when it is not working. Therefore, and lowest temperature Rated temperature The two values ​​are compared to determine the heat interaction between AEL and the thermal storage system.

[0069] The self-insulating operation method for alkaline electrolyzers (AELs) proposed in this invention achieves the following technical effects: 1) It realizes refined thermal management and on-demand heating for AELs under varying operating conditions: Based on the constructed dynamic temperature model, this invention fully characterizes the gradual temperature decay characteristics of the AEL under varying operating conditions and in shutdown standby states. By accurately predicting the temperature state at the next moment and combining the minimum temperature with the rated temperature for range judgment, it completely overcomes the crude control defects of the existing technology's "step-like" temperature change assumption and constant parameter continuous heat preservation, realizing intelligent on-demand heating that "supplements heat when needed, stores residual heat, and does not intervene when in a safe range"; 2) It significantly reduces the system's edge heat demand and ineffective energy consumption: By establishing a safe temperature range (case 2), this invention accurately utilizes the "heat-free window period" of the AEL's natural decay from the operating temperature to the minimum temperature. ; When the AEL temperature is within a safe range and not in operation, no insulation is required, avoiding ineffective heating and greatly correcting the problem of distorted and inflated heat demand assessment caused by continuous insulation throughout the process in existing technologies; 3) Effectively reduces the redundancy of the thermal storage system capacity configuration and lowers investment costs: Thanks to the precise reduction of the marginal heat required for insulation by the self-insulating operation strategy, the system does not need to configure excessively large heat exchange and storage equipment for inflated heat demand. This directly reduces the requirement for rated power of heat exchangers and rated capacity of thermal storage tanks in the planning stage of subsequent electric-hydrogen-thermal hybrid energy storage systems, thereby substantially saving the overall configuration investment cost of the system; 4) Balances equipment operation safety and hydrogen production smoothing efficiency: This method not only achieves energy saving and cost reduction, but also safeguards the bottom line of thermal safety; when the temperature drops below the minimum threshold (case 1), timely and proactive intervention is provided to effectively prevent electrolyte freezing, catalyst failure, or cold start delay caused by low temperature in the AEL, ensuring its rapid response capability to participate in smoothing offshore wind power fluctuations at any time; and it quickly raises the temperature to the rated value during operation, maximizing its hydrogen production efficiency.

[0070] Example: 1. Example Explanation: This invention, based on the technical requirements of the national standard "Technical Specifications for Wind Farm Connection to Power Systems Part 2: Offshore Wind Power," smooths out power fluctuations in offshore wind power with an installed capacity greater than 150MW and a time step of 10 minutes. The offshore wind power data used in this invention comes from measured power data of a certain offshore wind farm cluster from 2022 to 2023, with a total installed capacity set at 2500MW. Relevant parameters are summarized in Table 1. To ensure the accuracy of the configuration results, this invention uses the median cumulative power fluctuation as an indicator. K-means The algorithm selects two typical days from each of the four seasons, ultimately obtaining eight wind power output scenarios. The probabilities of each scenario are shown in Table 2. This invention uses the operating results and probabilities of the eight typical days as the operating data for the entire year.

[0071] Table 1 System Parameter Settings

[0072] Table 2. Probability Distribution of Typical Days

[0073] The framework of the hybrid electric-hydrogen-thermal energy storage system, which participates in mitigating power fluctuations in offshore wind power grid connection, includes the energy consumption and energy flow relationships of various devices, as follows: Figure 1 As shown, it consists of an electrochemical energy storage system, a hydrogen storage system, and a thermal storage system. The hydrogen storage system consists of three types of equipment: an AEL (Automatic Energy Storage Unit), a hydrogen storage tank, and a PEMFC (Power Equipped Utilization Mechanism). The thermal storage system consists of three types of equipment: a power waste heating device, a thermal storage tank, and a heat exchanger.

[0074] The configuration process for hybrid electric-hydrogen-thermal energy storage capacity is as follows: Figure 2 As shown, the mitigation task is divided into positive and negative fluctuation components: positive fluctuations are mitigated through charging of electrochemical energy storage systems or waste-to-energy heating equipment and hydrogen production via AEL, while negative fluctuations are mitigated through discharging of electrochemical energy storage systems or hydrogen production via PEMFC. The charging and releasing of hydrogen energy is handled by hydrogen storage tanks, while system heating is ensured by heat storage tanks recovering heat generated by waste-to-energy heating equipment, AEL, and PEMFC.

[0075] The boundaries of each typical daily dynamic interaction interval are obtained according to formulas (8)-(9), as shown in Table 3.

[0076] Table 3. Boundaries of Typical Daily Dynamic Interaction Intervals

[0077] According to formulas (39)-(40), the weights of each indicator in the capacity allocation evaluation system proposed in this invention are shown in Table 4. The weights of the primary indicators in the table are determined using the Delphi method, and the weights of all secondary indicators are uniformly set to 0.5 to avoid subjective bias. SOC deviation refers to the time... The ratio of the number of ticks to the total duration and the degree to which the average SOC deviates from 0.5 are each weighted equally. This indicator is used to quantitatively describe whether the SOC can quickly recover to an intermediate state and maintain an upper-middle level when the power curtailment heating equipment cannot participate, thus leaving enough capacity to smooth out negative fluctuations.

[0078] Table 4 Weights of Each Evaluation Indicator for Capacity Configuration

[0079] 2. Simulation results: To fully verify the advantages of the method proposed in this invention, three sets of simulations will be conducted, with the following factors considered in each simulation: Method 1: Ignore the dynamic temperature characteristics of AEL but consider an energy management strategy based on the dynamic interaction range; Method 2: Consider the dynamic temperature characteristics of AEL but also consider an energy management strategy based on a fixed interaction range; Method 3: Considering the dynamic temperature characteristics of AEL and the energy management strategy based on the dynamic interaction range, which is the method of this invention.

[0080] The final cost of capacity configuration for the three methods is shown in Table 5, and the schemes for each configuration are shown in Table 6. In addition, the average hydrogen production efficiency of AEL for method 3 is 69.04%.

[0081] Table 5 Configuration Costs of Each Method

[0082] Table 6 Configuration results for each method

[0083] 1) Analysis of capacity configuration results of Method 1 and Method 3 As shown in Tables 5 and 6, the total cost of Method 3 is 5.88% lower than that of Method 1. The main reason for this difference is that, compared with Method 1, Method 3 reduces the cost of hydrogen storage system by RMB 1.2966 million, the cost of thermal storage system by RMB 1.5546 million, and the cost of wind curtailment penalty by RMB 3.2805 million. The direct reason for this difference is that, under the same operating strategy, Method 3 is 4.42 MW lower than Method 1 in terms of AEL rated power, hydrogen storage tank rated capacity, thermal storage tank rated capacity, wind curtailment heating rated power, and heat exchanger rated power.

[0084] Specifically, in method 3, after considering the dynamic changes in AEL temperature, the temperature of AEL in the hot standby state is always higher than that of... In most cases, AELs do not require insulation, and the heat required to raise the temperature when transitioning from standby to production status is lower than in Method 1, thus significantly reducing the required rated power of the heat exchanger. Furthermore, after considering the dynamic changes in AEL hydrogen production efficiency, Method 3's average efficiency is 4.04% higher than Method 1. This allows Method 3 to produce more hydrogen to meet hydrogen demand, eliminating the need for additional hydrogen storage tank capacity and AEL rated power. In contrast, Method 1, due to its lower AEL hydrogen production efficiency, requires additional curtailment heating capacity to compensate for larger positive fluctuations, increasing costs. While Method 1 generates more heat to meet demand after planning additional curtailment heating capacity, resulting in a similar planned heat storage tank capacity as Method 3, curtailment heating does not participate in mitigating negative fluctuations. Consequently, significant negative fluctuations are difficult to mitigate due to insufficient power configuration in other equipment, ultimately increasing the cost of curtailment penalties.

[0085] In summary, Method 3, considering the dynamic changes in AEL temperature, has a more reasonable capacity configuration than Method 1, thus resulting in a lower overall cost for Method 3.

[0086] 2) Analysis of capacity configuration results of methods 2 and 3 As shown in Tables 5 and 6, the total cost of Method 3 is 14.04% lower than that of Method 2. The main reason for this difference is that, compared with Method 1, Method 3 reduces the cost of electrochemical energy storage configuration by 2.89%, the cost of thermal energy storage system configuration by 52.63%, and the cost of wind curtailment penalty by 51.63%. The direct reason for this difference is that, in terms of the configuration of rated capacity of electrochemical energy storage, rated power of curtailed power generation, rated capacity of thermal energy storage tank, and rated power of heat exchanger, Method 3 is 11.27 MWh, 53.42 MW, 12.65 MW, 12.76 MWh, and 36.01 MW lower than Method 1, respectively.

[0087] Specifically, Method 3 fully considers the ramp-up constraints of the AEL (Automatic Energy Utilization Unit) and the limitation that it cannot enter an operating range below 20% of its rated power when its power decreases. It formulates a more reasonable strategy than Method 1, enabling the AEL to operate at higher power levels more frequently while meeting all constraints. It also allows the AEL to participate more in the wind curtailment process, thus reducing reliance on the more expensive electrochemical energy storage. Method 3 uses lower-cost hydrogen storage tanks and increases the configuration of the AEL. Although this increases the configuration cost of the hydrogen storage system in Method 3, the increased heat generated by the AEL's greater participation in wind curtailment allows it to meet its own temperature requirements more often, thereby reducing the required rated capacity of the heat storage tank. Conversely, due to ramp-up constraints and low hydrogen production efficiency, the energy management strategy of Method 2 makes it difficult for the AEL to smooth high-power positive fluctuations. To compensate for this deficiency, Method 2 configures more rated power for wind curtailment heating, increasing the cost of the heat exchanger's rated power configuration. However, this wind curtailment heating does not participate in the smoothing of negative fluctuations, resulting in a large amount of negative fluctuations that are difficult to smooth due to insufficient power configuration of other equipment, ultimately increasing the cost of wind curtailment penalties.

[0088] In summary, the energy management strategy formulated by Method 3 after comprehensively considering various characteristics of AEL is more reasonable and has a lower overall configuration cost.

[0089] 3) Analysis of the results of the leveling performance Since Method 3 and Method 1 share the same energy management strategy, while Method 2 represents a significant improvement in energy management strategy, their comparison is the focus of operational analysis. This invention selects the operational results of both methods under a typical day 4 for analysis, and their power fluctuation mitigation results are as follows: Figure 3 As shown.

[0090] Figure 3(a) shows the typical daily power suppression task at each moment. Figure 3 (b) shows the power fluctuation smoothing at each time step under different methods. Method 3 has only 1.10 MWh of positive under-smoothing and 9.98 MWh of negative smoothing, while Method 2 has 6.22 MWh of positive smoothing and 18.12 MWh of negative smoothing, which are 5.12 MWh and 8.14 MWh higher than Method 3, respectively.

[0091] This difference is mainly due to the fact that Method 3 takes into account more of the dynamic characteristics of AEL when formulating its energy management strategy, thus reducing the undercompensation without the need for curtailed heating. In contrast, Method 2's unreasonable energy management strategy leads to excessive participation of curtailed heating in the task of mitigating positive fluctuations. While this can narrow the gap with Method 3 in terms of positive undercompensation, curtailed heating does not participate in negative fluctuations and other equipment configurations are insufficient, resulting in a large amount of negative fluctuations that are difficult to mitigate.

[0092] Depend on Figures 4-6 It can be seen that under Method 3, the AEL operating time accounts for 48.61% and the PEMFC operating time accounts for 24.31%, with 60 interactions between AEL and electrochemical energy storage; under Method 2, the AEL operating time accounts for 22.92% and the PEMFC operating time accounts for 23.61%, with 29 interactions between AEL and electrochemical energy storage. The AEL operating time and the number of interactions in Method 2 are 25.69% and 31 times lower than those in Method 3, respectively.

[0093] This difference stems from the fact that Method 3, when formulating its energy management strategy, considers more of the operational and energy consumption characteristics of the AEL (Alternating Energy Array), thereby enhancing the interaction between electrochemical energy storage and hydrogen storage systems while fully leveraging the greater smoothing effect of the AEL. Furthermore, because the interaction range of Method 3 is dynamically customized based on offshore wind power fluctuations, it allows the PEMFC to interact with the electrochemical energy storage earlier in cases of significant negative fluctuations. This keeps the SOC (State of Charge) between 0.36 and 0.68 for most of the time, maintaining a "shallow charge and discharge" state. This ensures that even without the need for curtailment of electricity for heat generation to participate in fluctuation smoothing, it has sufficient power and capacity to mitigate fluctuations.

[0094] In summary, the energy management strategy proposed in this invention is superior to method 2 in terms of smoothing effect. In other words, the energy management strategy proposed in this invention fully utilizes the smoothing performance of AEL and PEMFC, and by increasing the interaction time with telephone energy storage, it maintains SOC in the upper-middle range while better smoothing offshore wind power fluctuations at a lower cost.

[0095] 4) Comprehensive evaluation and analysis of hybrid energy storage capacity configuration for electricity, hydrogen, and heat The comprehensive evaluation results of the three different methods are as follows: Figure 7As shown, the comprehensive index scores for the three methods are 85.40, 80.92, and 86.17, respectively. Method 3 scores 0.77 and 5.25 points higher than the other methods, respectively. Method 3 outperforms Method 1 and Method 2 in both primary and comprehensive indicators, but has shortcomings in some secondary indicators. Specifically, Method 3 scores 2.16 points lower than Method 1 in the hydrogen storage capacity configuration indicator. This is only because Method 1 has a lower hydrogen production efficiency than Method 3, thus requiring more hydrogen storage tank capacity, and does not indicate that Method 1 is more inclined to use a hydrogen storage system. Method 3 only scores 2.22 points lower than Method 2 in the AEL start-stop frequency indicator. This is only because Method 2's energy management strategy fully utilizes the performance of the AEL. Taking a typical day 4 as an example, on a typical day 4, the number of AEL usages is 31 fewer than Method 3, with only 8 fewer start-stops. This is precisely why Method 2 scores 6.59 points lower than Method 3 in the wind curtailment penalty cost index. The uncontrollable fluctuations have a greater impact on the safety and stability of the power system, ultimately resulting in a lower score for Method 2 in the safety index. Furthermore, Method 3 has the highest SOC deviation index score, demonstrating that the proposed energy management strategy can better cope with high-power fluctuations. In summary, the method proposed in this invention is superior to Method 1 and Method 2 in both overall and hierarchical indicators.

Claims

1. A method for configuring the capacity of an electro-hydrogen-thermal hybrid energy storage system to mitigate sea wind fluctuations, characterized in that, Includes the following steps: Step 1: Construct a dynamic temperature model for the alkaline electrolyzer (AEL). This model is used to characterize the thermal state evolution of the AEL under varying operating conditions. Step 2: Based on the dynamic temperature model, and combined with the preset thermal safety threshold and minimum continuous operating time, formulate the AEL self-insulating operation strategy; Step 3: Based on the daily fluctuations in offshore wind power and the availability of thermal state that the AEL self-insulation strategy can maintain, construct a dynamic interaction interval model to determine the collaborative action boundary between electrical energy storage and hydrogen energy storage. Step 4: Based on the dynamic interaction range constructed in Step 3, construct an energy management strategy for the hybrid energy storage system; Step 5: Based on the dynamic temperature model in Step 1, the AEL self-insulation strategy in Step 2, the dynamic interaction interval model in Step 3, and the energy management strategy in Step 4, construct a capacity configuration optimization model for the electric-hydrogen-thermal hybrid energy storage system. With the minimum annualized total cost as the objective function, and the constraints of meeting the wind power fluctuation smoothing requirements, AEL thermal safety constraints, upper and lower limits of energy storage equipment capacity, and power coupling relationship within the dynamic interaction interval, solve for the optimal rated capacity of electric energy storage, hydrogen energy storage, and thermal energy storage, and construct a capacity configuration evaluation model.

2. The method according to claim 1, characterized in that, The dynamic temperature model constructed in step 1 is as follows: （1）； In the formula: and The first i sky t Time and t AEL temperature at +1 moment; For time step; and These are the equivalent thermal capacitance and thermal resistance of AEL, respectively; These are the fitting parameters; , and Each of the AEL numbers i sky t The power generated at all times, the power lost in heat, and the power exchanged with the thermal storage system.

3. The method according to claim 2, characterized in that, In dynamic temperature models, heat generation power models for: （2）； In the formula: , and These are the fitting parameters; For the first i sky t The per-unit value of the input power at time AEL; For the first i sky t Input power of AEL at time; In equation (2), the per-unit model of input power is: （3）； In the formula: This is the rated power of AEL.

4. The method according to claim 2, characterized in that, In dynamic temperature models, heat loss power models for: （4）； In the formula: For the first i sky t The ambient temperature of AEL at any given time.

5. The method according to claim 1, characterized in that, In step 2, based on the AEL dynamic temperature model and input power per-unit model constructed in step 1, an AEL hydrogen production efficiency model is constructed, as follows: （5）； （6）； In the formula: Use 0-1 variables to enable / disable AEL; For the first i sky t AEL hydrogen production efficiency at any given time; For the first i sky t AEL hydrogen production power at any given time; AEL generates heat during hydrogen production. If this heat is sufficient to meet the AEL's own temperature requirements, the excess heat is stored in a heat storage tank; otherwise, the heat storage tank needs to provide heat. Therefore, the AEL self-insulating model can be expressed by formula (7): （7）； In the formula: and The first i sky t Time and t At time -1, the thermal storage tank stores heat. For heat exchanger efficiency; , and The first i sky t At any given moment, AEL, proton exchange membrane fuel cells, and waste heat generation equipment transfer heat power to the heat storage tank; For the first i sky t The system's heat consumption at all times; and These are the power generation and heating efficiencies of PEMFC and abandoned power generation heating equipment, respectively. and The first i sky t Input power of PEMFC and abandoned power heating equipment at all times; For the first i sky t The thermal storage tank continuously transfers heat power to the AEL; and These are the thermal insulation coefficient and rated power of PEMFC, respectively.

6. The method according to any one of claims 2 to 5, characterized in that, Step 2 includes the following steps: Sub-step 2.1: According to equation (1), calculate the temperature of AEL at the next moment when the thermal storage system does not participate in AEL insulation. ; Sub-step 2.2: According to equation (5), the hydrogen production efficiency of the AEL is positively correlated with temperature. The higher the hydrogen production efficiency, the better the performance in smoothing wind power fluctuations. Therefore, when the AEL is working, its temperature should be rapidly raised to the rated temperature. In addition, the AEL should respond quickly when participating in smoothing wind power fluctuations, so a minimum temperature should be set to keep it in a hot standby state when it is not working. Therefore, and lowest temperature Rated temperature The magnitudes of the two are compared to determine the heat interaction between the AEL and the thermal storage system. Case 1) If If the AEL temperature drops below the minimum required level, intervention is necessary. Therefore, determine the AEL's operating status: If... This indicates that AEL is not working and heating must be activated to maintain it in a hot standby state. Therefore, according to formula (1), calculate... Required thermal power And heat it up, at this time , ;like This indicates that AEL is in operation and needs to be maintained and heated to the rated temperature to improve its hydrogen production efficiency. The heat is provided by thermal storage. Therefore, according to formula (1), the required [temperature] is calculated. Thermal power ,at this time , ; This operation prevents the AEL from failing to quickly meet the requirements for smoothing wind power fluctuations due to low temperature causing electrolyte freezing, catalyst failure, or cold start. Case 2) If If the temperature is within a safe range, then determine the AEL operating status: If This indicates that the device is not in use and does not require insulation, therefore it will not be updated. ,at this time ;like Then, based on equation (1), the judgment is made. Required thermal power ,at this time , ; Case 3) If This indicates that AEL has residual heat after meeting its own temperature requirements. This residual heat needs to be transferred to the heat storage tank for preservation. Therefore, the temperature is calculated. Greater than Partial heat power ,at this time Limit the temperature to ;and , .

7. The method according to claim 1, characterized in that, In step 3, a dynamic interaction interval model is constructed, which includes the following sub-steps: Sub-step 3-1) Obtain the normalized power standard deviation of offshore wind power and the maximum rise and fall rates of wind power: （8）； In the formula: and The first i Standard deviation of offshore wind power and its normalized value; The total number of hours in a day; For the first i sky t Real-time offshore wind power output; For the first i Average power output of offshore wind power in the sky; and The first i Maximum and minimum wind power output in the sky and offshore areas; and The first i Maximum rising and falling power of offshore wind power; and The first i Normalized rise and fall power of offshore and in-flight wind power; Sub-step 3.2) Based on the calculation results of sub-step 3.1), and combined with the AEL thermal state availability and time-series response capability determined by the AEL self-insulating strategy, a dynamic interaction interval model is constructed using formula (9): （9）； In the formula: and The first i The dynamic interaction range between TianAEL and PEMFC; and The first i Dynamic interaction range boundaries between TianAEL and PEMFC; , , , , and These are the dynamic interaction interval weights for AEL and PEMFC, respectively. The purpose of this operation is to dynamically set the interaction range according to the daily wind power fluctuations, so that the state of charge (SOC) of the electric energy storage will activate the AEL before it reaches the upper limit and the PEMFC before it reaches the lower limit. This can significantly improve the operating time and smoothing performance of the hydrogen storage system, and keep the SOC at an intermediate level, leaving sufficient capacity and space to cope with subsequent large power fluctuations.

8. The method according to claim 1, characterized in that, In step 4, based on the dynamic interaction interval proposed in step 3, an energy management strategy is constructed, which includes the following sub-steps: Sub-step 4.1) Assume that electrochemical energy storage is in the first... i sky t Power at time Specifically, if it is charging, it is indicated as If it discharges, it is represented as Power to be leveled And the remaining power to be mitigated after the first power allocation Positive and negative fluctuations are addressed separately. Positive fluctuations are mitigated by charging electrochemical energy storage, starting up AEL (Automatic Energy Source) hydrogen production, and activating surplus power for heat generation. Negative fluctuations are mitigated by discharging hydrogen using PEMFC (Power Equipped Momentum Controller) and electrochemical energy storage. The thermal storage system is only used when the power to be mitigated is at its maximum. Furthermore, the electric-hydrogen hybrid energy storage system will only participate in the smoothing process if there is still residual power to be smoothed after the smoothing process is completed; i sky t The maximum and minimum values ​​of AEL at time t are respectively under the ramp constraint. and ,at the same time It needs to be greater than 0; the input power of the AEL can reach 120% of the rated power, but there may be an explosion risk when its input power is less than 20% of the rated power. Therefore, it is necessary to avoid the AEL operating in this power range; if there is still residual power to be smoothed after all equipment in the electro-hydrogen-thermal hybrid energy storage system has been smoothed, it is considered as a shortfall. Sub-step 4.2) If the conditions shown in formula (10) are met, then AEL should be smoothed out as much as possible under the ramping constraint; if there is a remainder after AEL smoothing out, then the electrochemical energy storage will only participate in smoothing out when it was discharging or not working at the previous moment; at the same time, it should be noted that if To avoid AEL operating at low power, then Electrochemical energy storage discharge compensation AEL over-smoothing component: （10）； In the formula: For the first i sky t The state of charge of electrochemical energy storage at any given moment; This represents the maximum value of the electrochemical energy storage state of charge. For the first i sky t The hydrogen storage status of the hydrogen storage tank at all times; This represents the maximum value of the hydrogen storage state in the hydrogen storage tank. Sub-step 4.3: If the conditions shown in formula (11) are met, the energy management strategy is as follows: （11）； In the formula: Minimum state of charge in electrochemical energy storage; Case 1) If So, AEL only works in the previous period of time, that is At that time, AEL press and The maximum value participates in the smoothing, and the electrochemical energy storage smooths the remaining fluctuations. In addition, it should be noted that if there is an AEL over-compensation, the electrochemical energy storage needs to discharge to compensate for the over-smoothed part of the AEL. Case 2) If At this point, AEL presses first. and The maximum value participates in the smoothing process, and electrochemical energy storage compensates for the remaining portion; if there is still a surplus after the first power distribution, then only... Then, the power is redistributed again to AEL; Sub-step 4.4: If the conditions shown in formula (12) are met, the energy management strategy includes the following steps: （12）； In the formula: Minimum hydrogen storage capacity of the hydrogen storage tank; Case 1) If the electrochemical energy storage discharged at the previous moment, i.e. At this time, the electrochemical energy storage does not activate, and the PEMFC operates at its rated power. If there is overcompensation, the electrochemical energy storage will be charged. Scenario 2) If the electrochemical energy storage was charging or not working at the previous moment, i.e. And PEMFC worked in the previous moment, that is In this case, the electrochemical energy storage will not activate, and the PEMFC will operate at its rated power. If there is overcompensation, the electrochemical energy storage will be charged. Scenario 3) If the electrochemical energy storage was charging or not working at the previous moment, i.e. And PEMFC was not working at the previous moment, that is In this case, the electrochemical energy storage will first smooth out the power. If there is still power to be smoothed out after smoothing out the power, the PEMFC will be started again to smooth out the power. Sub-step 4.5: If the situation shown in formula (13) is satisfied, then the electrochemical energy storage will first be smoothed out. If there is still power to be smoothed out after smoothing out, then PEMFC will participate in the smoothing out. （13）。 9. The method according to claim 1, characterized in that, In step 5, the objective function for configuring the capacity of the hybrid electric-hydrogen-thermal energy storage system to mitigate ocean wind fluctuations is constructed, which includes the following sub-steps: Sub-step 5.1: Based on formula (14), construct the overall objective function for the capacity configuration of the hybrid electric-hydrogen-thermal energy storage to mitigate sea wind fluctuations, as follows: （14）； In the formula: Configure annualized total cost for capacity; , , and These are the total cost of electrochemical energy storage configuration, the total cost of hydrogen storage system configuration, the total cost of thermal storage system configuration, and the cost of wind curtailment penalty; Represents all decision variables during the planning phase; Sub-step 5.2: Based on formulas (15)-(18), construct the total cost function for electrochemical energy storage configuration, as follows: （15）； （16）； （17）； （18）； In the formula: and These are the investment cost and operating cost of electrochemical energy storage, respectively. and These are the unit power and capacity configuration costs of electrochemical energy storage, respectively. and Rated power and capacity of electrochemical energy storage; The discount rate; For the planning period; Unit maintenance cost for electrochemical energy storage; Costs associated with the degradation of electrochemical energy storage; The electrochemical energy storage lifespan degradation rate; The planned lifespan for electrochemical energy storage; Cost per unit lifetime decay of electrochemical energy storage; Sub-step 5.3: Based on formulas (19)-(21), construct the total cost function for configuring the hydrogen storage system, as follows: （19）； （20）； （21）； In the formula: and These are the investment cost and operating cost of the hydrogen storage system, respectively. and The unit power configuration cost for AEL and PEMFC are respectively; Unit capacity configuration cost of hydrogen storage tanks; This refers to the rated capacity of the hydrogen storage tank. Unit maintenance cost of hydrogen storage system; Costs associated with the degradation of hydrogen storage systems; For start-up and shutdown costs; This refers to the number of times an AEL is started and stopped within one cycle. and These represent the total number of days in the plan and the total number of hours in a cycle, respectively. Sub-step 5.4: Considering the life decay of AEL under three typical operating conditions—stable operation, fluctuating operation, and hot standby—a life decay model of AEL is constructed based on formulas (22)-(26), as follows: （22）； （23）； （24）； （25）； （26）； In the formula: , and The first i sky t Efficiency degradation of AEL under stable operation, fluctuating operation and hot standby conditions at all times; , and The first i sky t Efficiency attenuation coefficient of AEL under stable operation, fluctuating operation and hot standby conditions at any time; For the first i sky t AEL input power at time -1; and These represent the total efficiency decay and the total equivalent lifetime decay of AEL per day, respectively. and These are the rated and maximum hydrogen production efficiencies of the AEL, respectively. and These are the rated degradation coefficient and rated operating life of AEL hydrogen production efficiency, respectively. Sub-step 5.5: Based on formulas (27)-(30), construct the total cost function for configuring the thermal storage system, as follows: （27）； （28）； （29）； （30）； In the formula: and These are the investment cost and operating cost of the thermal storage system, respectively. and The unit power configuration cost for heat exchangers and abandoned power generation heating, respectively; Unit capacity configuration cost of thermal storage tanks; and These are the rated power of the heat exchanger and the power curtailment heating, respectively. This refers to the rated capacity of the thermal storage tank. Unit maintenance cost of the thermal storage system; Costs associated with the degradation of thermal storage systems; The lifespan degradation rate of the thermal storage system; The planned lifespan of the thermal storage system; Cost per unit lifespan degradation of the thermal storage system; Sub-step 5.6: Based on formula (31), construct the wind curtailment penalty cost function, as follows: （31）； In the formula: Penalty cost per unit; and The first i sky t Positive and negative deficits at all times; Sub-step 5.7: Constructing capacity configuration constraints for hybrid electric-hydrogen-thermal energy storage to mitigate ocean wind fluctuations, specifically including the following sub-steps: Sub-step 5.7.1: Construct power balance constraints based on formula (32), as follows: （32）； In the formula: and The first i sky t Real-time electrochemical energy storage charging and discharging power; Sub-step 5.7.2: Construct electrochemical energy storage power capacity constraints based on formulas (33)-(34), as follows: （33）； （34）； In the formula: For the first i sky t Electrochemical energy storage state of charge at time -1; For electrochemical energy storage conversion efficiency; Sub-step 5.7.3: AEL can operate at 20% above the rated power, but there is an explosion risk when operating below 20% of the rated power. Therefore, the power capacity constraint of the hydrogen storage system is constructed based on formulas (35)-(36), as follows: （35）； （36）； In the formula: For the first i sky t -1 is the hydrogen storage state SOHC; and These are the hydrogen density and lower calorific value of the hydrogen storage tank, respectively. Sub-step 5.7.4: Construct the power capacity constraint of the hydrogen storage system based on formulas (37)-(38), as follows: （37）； （38）。 10. A self-insulating operation method for alkaline electrolyzers (AEL), characterized in that, Based on a dynamic temperature model, and combined with preset thermal safety thresholds and minimum continuous operating time, an AEL self-insulating operation strategy is formulated, including the following steps: Step 1: Calculate the temperature of the AEL at the next moment when the thermal storage system does not participate in the AEL insulation. ; Step 2: and lowest temperature Rated temperature The two values ​​are compared to determine the heat interaction between AEL and the thermal storage system.

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